Irish Weather Statistics

sryanbruen

Given the pattern this coming week, thought it'd be a good time to mention this event.

Mid-February 1973 brought in a northwesterly flow and low pressure disorganised from Iceland. It slid down the country and eventually went to the east of the country. In its wake, it left a temporary significant covering of snow especially in the Midlands.

Clones (Monaghan) recorded a snow depth of 25cm, its record snow accumulation before it closed in 2008. Between 12-23cm of undrifted snow was seen in Northern Ireland which some had their heaviest February snowfall since 1947 according to the Met Office. I'd say Danno would have a lot of fun with this one if it were to occur now.

An interesting event considering the synoptics and the period it occurred - the early 1970s which have been widely regarded as a very boring period for weather in the UK & Ireland.

sryanbruen

I've probably done a post on this before but I can't remember and can't be bothered to look back. Nonetheless, this will undoubtedly be better than the previous if so.

Winter 1990-91 was a relatively cold winter with cold zonality at times during December 1990 and January 1991. The latter brought significant snowfall in the second week of the month with as much as 15cm at Casement and 20cm near Naas. However, the most notable event of this winter was the easterly spell in early to mid February.

High pressure that had established around Ireland on 21 January 1991 built over Scandinavia through the final few days of the month and into February. In mid-January, a significant warming of the stratosphere occurred which could have aided in the development of this Scandinavian anticyclone. The Atlantic was primed to bring explosive cyclogenesis our way from a deep vortex over Greenland in a similar fashion to the previous two months with the 5th of January especially being infamous. However, the way the depressions were angled allowed warm air advection into higher latitudes which would only inflate the Scandi high into a stronger blocking area of high pressure and keep the Atlantic depressions at bay. Initially the winds veer south for Ireland bringing in temporarily milder conditions compared to the frosty anticyclonic conditions of late January but we would soon find ourselves in an easterly flow.

The chart for 4th February 1991 illustrates this perfectly. We have a strong vortex over Greenland but the Scandi high has overpowered this and ushered in easterly winds into Ireland but there is a dissipating belt of rain over the midlands and south of the country from the prior southerly winds mentioned. At this stage, temperatures are around average for early February and frost was limited. It would take up to the 6th for some genuine cold air to arrive near our shores then the beast was unleashed from the east on the 7th.

So the 7th of February 1991 was the day the beast was unleashed into Ireland. Southeast England was getting pummelled by the white stuff with London experiencing its worst snowfall in modern times and St. James' Park in central London having a depth of 20cm. The effects in Ireland weren't nearly as historic on their scale but nonetheless, snow showers from the Irish Sea were blown in by the easterly wind to coastal southern and eastern parts of the country. Depths were up to 10cm at Dublin Airport and Casement by the 9th and 10th February. Usual stuff that you'd expect happened such as traffic coming to a standstill on roads in Dublin and Cork. Ice day conditions were observed for some on the 7th.

The convection was relatively short-lived but further light falls happened in eastern areas for a few days though these intensified again later in the evening on the 9th for a time.

The anticyclone over Scandinavia weakened a lot by the 10th, by this time the wind veered northerly and snow shower activity died a death but this also resulted in widespread crisp winter sunshine and severe frosts. The air temperature fell down to -13.2C at Gowran Grange near Naas, the lowest temperature in Ireland in a decade since January 1982. Snow cover made the difference there as no other location got close whilst the Dublin stations often had an onshore breeze with Casement getting down to -8.0C.

There was up to 6 days of snow lying at 9am at Casement and Dublin Apt.

The snow cover lasted to the 12th when troughs brought rain to parts of the country and a milder westerly flow established bringing an end to the cold spell. The rest of February 1991 was generally on the mild side.

Snow cover in Howth on the 10th February 1991 after a night of heavy snow, pics courtesy of Declan Smith.

The 54 in a snowy Tallaght in February 1991, pic courtesy of Jonathan McDonnell.

sryanbruen

Early 1965 was quite often blocked with various weather extremes. January was rather changeable with a New Year northerly blast replaced by a zonal mid-month period and a cold easterly to end. Shannon Airport supposedly had a maximum of -1.8C on 4th January 1965, looking at the synoptics the only way this would have been possible was persistent freezing fog as high pressure by that point toppled over us and the northerly flow was cut off. There was widespread frost from this with -7/-8C typically seen inland including -8.8C at Kilkenny on the 5th.

There were a few snow events including Irish Sea streamers during the easterly but nothing too outstanding comparing to other events away from higher ground where Wicklow had significant accumulations in late January. RTÉ report on the village of Ballyknockan, 220m ASL getting snowed in here. Unlike two years prior, whilst roads were impassable, residents were more prepared this time around. Casement Aerodrome had a snow depth of 6cm on 29th January 1965 at 9am. There were no ice day conditions reported from this easterly at any of the stations. The lowest minimum temperature was -7.5C at Glenties on the 29th.

Until the final day of the month, February 1965 was universally dominated by high pressure and is one of the driest months on record Ireland has had. Parts of the country were completely rainless throughout February including Galway. Belmullet had a monthly mean sea level pressure of 1032 hPa during this month, that's just over 20 hPa above average. February 1965 holds the record highest daily mean sea level pressure for the month of February in many parts of the north, whilst the prior February 1964 holds the national record but both contained intense anticyclones.

In the final week of February, the anticyclone retrogressed to Greenland and we found ourselves in a very cold northeasterly on the final day of the month leading us into a severe cold and snowy start to March. March 1965 was one of the most interesting months with a big temperature swing between the first week and the final week. This northeasterly brought snow showers and bitterly cold conditions with a minimum temperature of -11.0C at Boora on 2nd March. There was no ice day conditions - as referenced before, 2018 was the first March ice days seen in Ireland since digitised records began in 1942. Nonetheless, this did not take away from how cold and wintry it was.

Deep low pressure formed within the cold airmass and gave further heavy snow, especially inland on 3rd and 4th March. The max snow depth I have is 8cm at Casement but there was definitely more for others where measurements were not taken. This snowy weather very quickly receded however with high pressure toppling in over us by the 6th and it was significantly milder for most though road conditions continued treacherous in the mountains.

Mid-March 1965 brought in southerly winds with high pressure to the east trying to keep the Atlantic at bay. The brief severe wintry weather was a long distant memory. It became changeable and unsettled shortly after the second week before high pressure ridged from the Azores on the 28th.

As the ridge came north, it brought along with it quite warm air for the time of year. 28th/29th March 1965 broke March maximum temperature records in the UK & Ireland. It achieved 25.0C in England whilst Trinity College in Dublin got up to 23.6C. This is a record that holds true to present day. We would not see such warmth in the month of March again in Ireland until 2012. In places, 28th March was the warmest day of 1965 which gives away how poor the following summer was. March warmth a bad omen for the summer some say? Certainly was the case in both 1965 and 2012. Then again, the summers of the 1960s were generally poor for warmth and fine weather and 1965 wasn't unique.

March 1965 holds the highest temperature range for any month on record in the UK from -21.7C on the 3rd to 25.0C on the 29th (a range of 46.7C!). Meanwhile, Ireland went from -11.0C on the 2nd to 23.6C on the 28th (a range of 34.6C). For a single station, Casement had a range of -9.6C on the 2nd to 21.0C on the 28th/29th (a range of 30.6C).

RTÉ report of people flocking to the seaside to enjoy the March warmth here.

An interesting few months to start 1965. Don't forget the cold and snowy or very wet, depending on location, November 1965 that followed too. 1965 wasn't without its interest!

Irish Photo Archive have some photos on the March 1965 snow such as below.

sryanbruen

The coming few days will be the 90th anniversary of one of Ireland's most infamous snowstorms, that of February 1933. A complex low pressure system developed over Ireland on the afternoon and evening of the 23rd moving slowly southward, deepening in the process. The vast majority of precipitation over Ireland consisted of snow and it persistently fell in places for a good 72 hours before the thawing started to occur and ushered in relatively milder southerly winds by the 27th with the low deepening further to our southwest.

Level snow in places was reported to be between 1-2ft deep with massive drifting. This included 30cm at Broadford (Co. Clare) and 6-10ft drifts at Hacketstown Rectory (Co. Carlow). 30-60cm was common over Leinster, particularly the Midlands and the south. Ireland was reportedly cut off from the rest of the world.

A letter from Patrick McDonnell of Ballinlough (Co. Roscommon) discusses the impacts of the snowstorm in his area and gives a personal account - it was supposedly the worst snowstorm in Roscommon since 1867. Visibility at one point on the Friday evening (24th) was reportedly barely 2 yards ahead. Children had to be defrosted. If you haven't read about it by now, you should do so. It's unbelievable to think this was Ireland, a film could be made about this 1933 snowstorm. Here's the link.

The strong easterly wind, which gusted to 78 mph at Holyhead or 85 mph at Calshot in southern England, blew down telephone poles, trees and left the roads impassable for many days evening directly on the coast such as Balscaddan near Balbriggan (Co. Dublin). Carts, bread-vans (imagine the bread memes now) and horses could not move for days.

Another letter from Rosie Mulligan of Celbridge (Co. Kildare) gives further evidence of 4-10ft drifts of snow with Wicklow suffering intensely. There was no school and getting out to play was dangerous. The majority of sheep and other animals perished.

Irish Daily Times have colourised footage of an old British Pathé reel showing O'Connell Street in the tweet below but I've also given the YouTube link to those of you who prefer the black and white.

https://twitter.com/irishdailytimes/status/1600549255000866838?s=20

https://www.youtube.com/watch?v=eZv2xUKkRc4

Ashbourne Road, near Finglas in the 1933 snow.

sryanbruen

10 years ago, we found ourselves in what would become Ireland's coldest March since 1937. Many individual stations had their coldest March on record, including Dublin Airport. The well below average mean temperatures came from the result of persistently colder than average temperatures rather than anything exceptionally cold compared to say the easterlies of March 2018. However, outside of the easterlies, much of March 2018 was relatively milder or average temperatures so 2013 is a significantly colder month generally speaking. Mean temperatures were 2-3C below 1981-2010 averages and mean maximum temperatures were as much as -4.5C below average at Glasnevin. Dublin Airport did not even achieve a single day with 10C or more. There was plenty of snow falling days (up to 11 days at Dublin Airport) but rarely did the snowfalls amount to much as you'll find in my analysis here on the month, again unlike those seen in 2018.

The month began on a benign note, continuing the very dry period that set in mid-February. Temperatures were average to below average with frost by night in limited locations but quite sharp where it did occur. Sunshine was sparse. Winds east to northeast later veered southeast as high pressure attempted to split into two with one cell retrogressing to Greenland and the other dropping into Europe.

Low pressure approached from the southwest by the 6th and gave a few days of wet, damp and relatively mild conditions with temperatures generally speaking in the low teens. A miserable couple of days up to the 10th.

The low pressure weakened by the 10th and undercut to the south of Ireland intensifying the easterly flow to near gale force. As the rain cleared to the south, wintry showers fed in from the Irish Sea over Leinster overnight into the 11th.

The 11th was the coldest day of March 2013 with a strong northeasterly flow bringing maximum temperatures down to only 2-3C mostly whilst Mount Russell (Co. Limerick) and Killucan (Co. Westmeath) had a max of just 0.8C. There was frequent widespread snow showers during the afternoon but accumulations were limited away from Waterford later in the evening where a match at the Waterford RSC had to be called off. Here's a video from mickger844posts on this snowfall.

Always found it strange how there wasn't more snowfall on the 11th than there should have been given the low heights and the very cold 850hPa temperatures. Only explanation I have ever thought of is the sea surface temperatures were colder than average at the time so the temperature contrast wasn't sufficient to produce large CB towers and give intense precipitation. The time of year shouldn't matter if the precipitation is intense enough.

The flow became more northerly on the 12th and away from some light snowfalls in the southeast, much of the shower activity died off. It was the coldest morning of the month with temperatures as low as -7.6C at Markree Castle - lower temperatures were seen in March 2001 and 2010 this century.

Low pressure descended from Iceland by the 15th after a couple brighter days. This brought rain at first and clearing the east coast by morning. Hail showers developed after. It was temporarily milder for a time with temperatures more average for the time of year. As Greenland blocking intensified again by St. Patrick's Day, it turned colder again with some of the precipitation turning wintry.

The blocking in high latitudes became very intense by the 19th and 20th stretching from Canada to Siberia. The zonal flow was in reverse with long fetched easterly winds. There was periods of rain in the south early on whilst widespread, frequent wintry showers consisting of hail, sleet and snow followed in the days ahead. Accumulations were limited again. Daytime temperatures still managed to get up to 4-7C mostly and even reaching double digits locally showing how much effect the time of year is making here. This would likely be an ice day setup in the heart of winter.

A depression approached from the southwest on the 21st and for most of the country gave way to heavy rain. Totals were up to 98.9mm at Glenmacnass (Co. Wicklow). There was flooding reports in Meath, Wicklow, Cork and Dublin. Dart services had to be suspended from flooding on the line.

In stark contrast, the rain as it bumped into the cold air turned to snow in the north of the country. The likes of Donegal had snow turn to rain after a while as the mild air successfully won temporarily here but the east of Northern Ireland stayed in the cold air and the snow was very bad here. Northern Ireland likely had its worst snowfall since 1962-63 with deep drifting up to 12ft. Over 137,000 were without power. Parts had to wait until the second week of April for all of the snow to disappear.

A video showing the deep snow in NI.

The depression filled by the 24th and the easterly flow was renewed bringing the cold air back again to all. At first it was mainly dry and cloudy. The max temperature at Knock Airport on the 24th was only 0.9C. Light flurries of snow began to appear in off the Irish Sea on the 25th and 26th but accumulations yet again limited from these.

There was more significant snow showers in off the Irish Sea overnight the 26th into the 27th and Casement Aerodrome woke up to a 6cm accumulation. Widespread parts of the east had a covering which had all melted before midday. There was further snow showers throughout the day, mainly light. These continued into the 28th with a renewed 2cm covering at Casement. By the afternoon of the 28th, all shower activity had died off and apart from some rain in the southwest on Easter Sunday the 31st, it was dry for the rest of the month across the country.

Easterly winds were still ongoing into early April 2013 with further cold weather. In fact, the 1st April 2013 was the coldest April day for many since 1966. The maximum temperature at Edenderry (Co. Offaly) was only 3.5C with persistent cloud. Cloud broke up in the days after which was a relief after such a cloudy, easterly dominated March but this also meant some harsh frosts at night.

Mount Dillon had a minimum temperature of -7.3C on the 6th April, this was the lowest April temperature in Ireland since 1988. Dublin Airport with -5.6C and Mullingar with -6.5C had their coldest April temperatures on record. This was the last of the significantly cold weather but it continued cooler than average on and off up to the first week of June with Ireland having its coldest spring since 1979.

M.T. Cranium

I remember the general surprise about the lack of snow in March 2013 but I think Waterford had one day where it snowed more than anywhere else in Ireland. For readers of this thread who are familiar with our contest, the IMT for March 2013 was 3.6 (1981-2010 average is 6.8). Our lowest forecast for the month was 5.0 from dasa29, and our consensus was close to normal, so even though February had been rather cold, few foresaw that the month (which started with a fairly bland first nine or ten days) would turn so cold. Our lowest predicted minimum was -6.6 while the actual minimum was -7.6. The maximum for the month was only 14.3 (Athenry 8th). The warmest value in Ireland on 17th was 9.0 at Sherkin, two of our long-time contest entrants (Kindred Spirit 8.0, Joe Public 9.9) were the only ones to guess below 10 for that.

It has been a couple of years since I looked back on net-weather at their contests for extreme months, but IIRC it was a similar situation in their contest, the lowest forecasts were in the 4 to 5 range. Even Dec 2015 had a smaller absolute error but then it was looking very mild at the outset.

By the way, the outcome of our contest in Dec 2015 was that the IMT of 8.2 was 1.2 above the best forecast of 7.0 from rikand. The PRC value in that contest was 266%.

Charles Babbage

https://www.boards.ie/discussion/comment/120397591#Comment_120397591

If you regard "Ireland" as having only 26 counties then a lack of snow may have been the case.

In the real Ireland it was like this in late March 2013

Oneiric 3

Messing around with this very interesting dataset provided by Met Eireann:

https://www.met.ie/daily-rainfall-and-temperature-grids/

It is really amazing what you can discover about the climate at the nearest grid point to one in any part of Ireland. Here is an example of the nearest point to my location (144000 - 252000) regarding the probability of seeing a totally dry day on any day of in the year based on a 61 year average:

As can be seen, the chance of getting a totally dry day gradually increases from Jan through to June, but decreases again from July onwards, with August in particular seeing some of the lowest probabilities of the year!

Amazing dataset to play around with to get a sense of one's very local climate. They have daily temp and rainfall data available in this regard but would be great to see them including some wind speed and directional data in this set as well to help us create a more full-bodied climate profile.

sryanbruen

Time for a historical post as I haven't done one here in a while. This is going to be on the summer of 1997. There's a very specific reason why I choose this particular summer - coming into the summer of 2023, the long range seasonal model runs were projecting a very similar pattern to what was seen in 1997. That is high pressure primarily over Scandinavia with low pressure over Biscay drawing in a humid, warm easterly flow. However, as far as the months go in summer 1997, they're not quite as straightforward as that.

To start off, May 1997 was a month of wild swings. The first few days and final few days were warm and sunny whilst there was a protracted changeable period inbetween including a notably cold northerly blast coinciding with the May day bank holiday. Much of the rainfall was of the showery nature rather than prolonged outbreaks of rain.

After a few warm days at the start, the wind quickly veered northerly through May Day and into the 6th drawing in a very cold airmass for the time of year. The -8C isotherm touched the northeast of Ireland before the airmass moderated via daytime heating. This brought snow showers and isolated thunderstorms to parts early in the day. Fethard (Parsonshill), Co. Tipperary woke up to a min of -1.6C the next day. More snow showers occurred on the 7th. This was the first May snow for some since the exceptional cold first few days of May 1979 when there was measurable snow lying on the ground. Many have not seen snow in the month of May since 1997.

High pressure ridged in during the final week of May from the east. This brought prolonged spells of sunshine nationwide with high temperatures for the time of year including a national May record set in Kerry on the final day where Ardfert achieved 28.4C beating the previous May record of 27.8C back in May 1922. It was cooler on the east coast due to the easterly nature of the wind.

Valentia Observatory had 246 hours of sunshine during May 1997 with almost half of this being recorded between the 24th and 31st indicative of just how sunny the period was.

That fine, warm end to May brings us into June 1997 which starts where May left off. However, this would be a false sign of summer as June would actually turn out to be a very wet and generally cool, cloudy month. It was the wettest June on record at Rosslare whilst other parts of the southeast had their wettest June since 1982. The far north fared relatively better as the jet stream was southerly tracking. Daytime temperatures were mostly well below average and more than 2 degrees below par at Casement Aerodrome. Casement also had its cloudiest June since 1987 with only 58% of average and 108 hours of sunshine whilst Malin Head was nearer average.

The easterly wind picked up pace on the 1st June and it wasn't nearly as warm as late May with 24.4C at Ardfert being the highest value achieved. Fairly cool in comparison on the east coast with values of only 15C. Some showers started to develop from the 3rd but the pattern did not truly breakdown until the 5th.

By the 7th June, any high pressure influence was a distant memory and deep low pressure approached from the southwest giving strong to gale force southerly winds on the south coast.

This low set the scene for June 1997 with low after low bringing rain at times and generally cloudy conditions. Temperatures very suppressed, particularly in the final week where places had numerous days of only 12 or 13C. The 26th was particularly cool with a fresh north to northeasterly flow but there was good sunny spells in spite of the poor temperatures.

So June 1997 for the most part was rather grim, does the summer see an improvement through July or was the May warmth the peak of the "summer"? July did not get off to a good start at all if it's warm, dry weather you seek.

In fact, 1st July 1997 was record breakingly cool for the time of year with maximum temperatures more appropriate for March in a northerly flow. The lack of sunshine and later rain into the 2nd aided the record low daytime temperatures. Casement had a maximum of 10.6C all day on the 1st whilst Malin Head had 10.2C, Clones 10.7C and Mullingar 10.9C. These values are more than 7 degrees below average.

Further cool weather occurred until the 5th when the Azores high started to ridge in from the southwest. The north was rather cloudy but there was good sunshine in the south and east. Temperatures got a nice boost into the low 20s in any sunshine and later mid-20s. This, aside from some downpours that I'll get into, set the scene for July 1997 which despite the exceptional cool start actually turned out to be a relatively warm, mostly dry and sunny month. Don't judge a book by its cover as they say or in this case, don't judge a month by its opening period as it can change dramatically.

The wind later veered more east or southeast bringing in sea fog to the east coast at times.

As high pressure pushed eastward over Scandinavia by the 10th, thunderstorms occurred in the west. An Atlantic depression on the 12th attempted to dislodge the warm air and the result was some intense thunderstorm activity, particularly in Mayo. Severe flooding occurred near Bangor Erris after 50mm of rain fell within a 2-hour period.

After a more showery period, high pressure returned by the 18th July and lasted to the 22nd. This brought the warmest weather of the month with a maximum temperature of 25.7C at Ardee and Kilkenny on the 22nd. Nothing notable but fine nonetheless.

The last week of July was more changeable in nature with some slow-moving downpours on the 22nd into the 23rd.

That takes us into August 1997 which was an extreme month. First it was exceptionally warm but in terms of mean temperature/mean maxima not as warm as August 1995 - only 2 years prior. Mean minima on the other hand were record-breaking being the highest on record at Casement and Birr. Overnight temperatures of 13-18C were typical during the period 4th-21st August, well above average. There were no instances of tropical nights however.

Secondly, it was extraordinarily wet in the south of Ireland with a severe rainfall event coinciding with the August Bank Holiday. This one wet period from the 3rd-6th guaranteed the wettest August on record in Cork and Wexford.

Following an initial rise in pressure, heights lowered over the south of Ireland on the 3rd/4th. This small upper level trough became stationary here for 3-4 days and eventually dissipated later on the 6th. Apparently the models at the time predicted this trough would track southwards instead of going northwards towards the south of Ireland. I can imagine that not going down well with people if it were to happen today and Met Éireann would get so much backlash.

On the 3rd alone...

Johnstown Castle 110.6mm (over 190mm up to the 6th)

John F. Kennedy Park 96.2mm

Clonroche 94.6mm

Rosslare 89.2mm

Cork Airport 87.1mm

RTÉ broadcast on floods in Tipperary and Clare from this severe rainfall event here: https://www.rte.ie/archives/2022/0711/1309635-floods-follow-heavy-rains/

Following this event, a prolonged warm period to the 22nd commenced with various wet days and thunderstorms from time to time - most notably on the 10th and 11th.

The highest temperature of the month was 26.1C at Kilkenny on the 8th. Temperatures themselves weren't anything exceptional but it was the persistence and the mild nights that made August 1997 so warm. Saying this, Malin Head had 25.9C on the 11th - its highest August temperature since 1955.

Some footage on a thunderstorm in 1997 - most likely the 10th/11th August - from highdef: https://www.youtube.com/watch?v=aAEGqTCyrhk

On the 26th as the high pressure to the east declined, an Atlantic depression brought more heavy rain to the south and southwest with Cork again badly hit. Freemount in north Cork recorded 58mm. Rivers were overflowing and bursting banks. This ends August 1997 on a classic autumnal, unsettled note.

Overall, summer 1997 was very divided between the north and south. Malin Head had one of its better summers and was relatively dry, warm and sunny whilst it was the wettest summer on record in the south - especially Wexford. Will 2023 fare similar to this summer? There's definitely some similarities so far but June 2023 is much warmer and sunnier than June 1997.

sryanbruen

A few newspaper extracts from the summer of 1997.

Mayo News 16th July 1997 - Bangor Erris thunderstorm

Evening Herald 5th August 1997

Irish Examiner 6th August 1997

Irish Independent 7th August 1997

Irish Examiner 27th August 1997

Irish Examiner 1st September 1997

sryanbruen

The Met have now finally released the 1991-2020 averages for Ireland after waiting 2 years so my first action was of course to compare 1991-2020 to the previous 30-year period 1981-2010.

The table below is of Casement's climate anomaly changes between the two climate periods. The most interesting points I note from this:

• How very wet November has become followed by February and July.
• March has had a tendency for colder nights despite a slightly higher mean max including a significant increase in ground frosts and almost half a day of snow lying (mind the days of snow lying only apply to 0900 UTC). Sudden stratospheric warming events have increased March tendency for snow? Sunnier Marches mean clearer nights, therefore more cold nights under light winds?
• August is the only one that has seen a decrease in monthly rainfall and it also has the second highest increase in mean daily sun duration.

sryanbruen

Looking through the new 1991-2020 averages PDF, they give this monthly rainfall comparison map with changes from 1961-1990 to 1991-2020. If I look at them on a month by month basis, the east has gotten slightly drier in January though not too significant away from parts of Kildare, Wicklow and southwest Dublin whilst the west has gotten slightly wetter but again, not that significant.

February the change is much more stark with the northwest getting a huge increase in February rainfall which makes sense as dry Februaries have become a premium it seems compared to back in the day. Surprised with supposedly the south and southeast going drier though. More westerly and less easterly?

March is drier for the southwest but otherwise not much change across the country.

April has gotten nationally wetter which does surprise me as many Aprils this century have been on the drier side.

May has seen a negligible difference across the board with some wetter, some drier though more drier.

June slightly wetter across the country, especially across the south.

July has seen the biggest increase in rainfall nationally overall with all places experiencing an increase but especially the northwest, west and southwest. This makes sense as though many Julys back in the day were cool, they tended to not be on the overly wet side with some exceptions like 1988. However, Julys since then have been wet a lot of the time especially from 2007-12 which contained several exceptionally wet ones.

August is similar to May with negligible difference generally speaking but leaning more towards the wetter side for most.

September has an interesting drying trend for the northwest which I didn't anticipate.

October also has a drying trend for the northwest but in contrast has an increase in rainfall for the southeast. October is already the wettest month on average for this region.

November sees one of the biggest changes with being very wet from an already wet base. Given the frequency of wet Novembers being extremely wet, this doesn't come as a surprise.

December sees a drying trend for sheltered eastern areas whilst most of the west away from a localised part of Kerry shows a wetter trend, indicative of an enhanced westerly flow in the month. Not surprising comparing Decembers this century to say the 60s - the latter was known for its cold Decembers.

sryanbruen

For the next historic weather post, I'm going to take a look back at the summer of 2022 which of course will be fresh in many people's minds as it was only a year ago but I think this is an important one to do a post on.

The summer of 2022 was a dry and warm one with record-breaking temperatures set during July and August. It was the 6th warmest over Ireland since 1900. However, before we get to the heat, let's start from the beginning. The start of summer 2022 was actually relatively cool, especially by night at first with low digits being recorded including a minimum temp of 2.1C at Mount Dillon on the 2nd under a slack northerly flow continuing where May had left off. There was some rain that pushed eastwards on the 2nd but most of the first 4 days had good sunshine and scattered showers despite the cool temperatures which were generally in the low to mid-teens.

A shallow trough to the south of Ireland brought in rain to the south and east on the 5th and winds veered easterly. Rain was on the low side but the daytime temperatures were especially suppressed on this day. Casement and Dublin Airport had maxima of only 11.3C. The north and far west were significantly warmer, even reaching 20.4C at Belmullet with good spells of sunshine.

A few more settled days followed with good sunshine at times in the east but fairly cloudy elsewhere with some light rain in the west and average temperatures for the time of year. Low pressure pushed in from the Atlantic on the 8th with increasingly blustery conditions and plenty of light outbreaks of rain. A few very windy days for the time of year succeeded as deep low pressure with a central pressure of 973 mb neared the northwest of Ireland. There was lots and lots of showers during the 10th and 11th with gale force westerly winds, sustained up to 63 km/h at Belmullet and gusting to 83 km/h.

High pressure ridged in from the south for the next week as the deep depression cleared and filled. There was light rain, drizzle and showers at times in the north but it was mostly dry until the 17th with bright spells on occasion though it wasn't a very sunny high pressure.

Warmer air arrived from the south on the 15th peaking on the 16th with a max temperature of 23.9C at Phoenix Park. This was short-lived as the Atlantic already broke through on the 17th veering winds to a northwesterly direction. There was rain widespread on the 17th whilst most of western Europe was getting impacted by a big plume of heat which had looked like it could break the June max temperature record in England but this did not come off. However, maybe this was a warning sign from nature of what the rest of the summer would be up to?

A dry, cloudy few days were to follow and then there was widespread unbroken sunshine on the 20th as a ridge of high pressure influenced Ireland's weather. Cloud later arrived from the northwest during the evening. Mount Dillon had a maximum temperature of 23.8C. This cloud would be persistent over the country until the afternoon on the 22nd as the northwesterly wind fed in cloud off the Atlantic.

The ridge of high pressure disappeared and was replaced by low pressure by the 24th with lots of rain countrywide though good sunshine in the east on the 25th. Valentia had as much as 41.6mm on the 24th - its wettest June day since 2007. This low pressure circulated around the country and would only be replaced by further low pressure from the Atlantic giving a very wet end to June 2022. Valentia had up to 109.5mm from the 22nd-28th June - its 2nd wettest June week since 1939. Thoughts were on where is summer and whether it would ever show. Well in fact, it was around this time that the GFS started hinting at extremely hot weather in its extended range output towards mid-July. Of course at this time they were treated with truck loads of salt as they were outliers but the warning sign was there that they were showing as a possibility. They hinted at 40-42C over England with Ireland achieving 30C.

I will continue onto July and August 2022 tomorrow but summer 2022 was off to a slow start with a pretty unsettled, changeable June especially the end. Did July quickly see a changeover to something more settled?

sryanbruen

This is my second draft of the post as I accidentally closed the tab for Boards 🤦‍♂️ this is why I appreciated the autosave draft feature of new Boards even though at times it did get annoying. As I'm doing it, I'll remember to save draft this time!

Unlike June, July 2022 was a dry month mostly dominated by high pressure but the centre of the high tended to be to the south and southwest of Ireland which resulted in cloudy maritime Atlantic air filtering around the anticyclone. It was the driest July since 1989 at Shannon Airport with only 20.7mm of rain all month. All places had a drier than average month. It was a very warm month but away from Phoenix Park and Dublin Airport, all other stations had it warmer in July 2021. This month is most well-known for its extreme heat mid-month brought about by a record-breaking plume of tropical continental air from Iberia. The south fared significantly better in the sunshine than the north as you'd expect in July and given the pattern with up to 188 hours at Johnstown Castle but only 90 hours at Belmullet.

The start of July continued where June had left off with relatively low pressure bringing showers and mostly cloudy conditions. Temperatures were also somewhat below average for the time of year. High pressure began to exert its influence from the southwest on the 5th making in roads to Ireland by the 7th with a central pressure of 1037.3 mb recorded at Valentia. That is exceptionally high atmospheric pressure for the time of year and in fact, it is only 0.6 mb off the national July record set back in July 1933. Temperatures responded to the cloud breaking up getting up to 25.0C at Mount Dillon - the highest temperature of the summer so far but of course this would be beaten many times. The north remained cloudy however and this would set the scene for the next few days with the south having good sunshine but much of the country under the cloudy maritime airmass though at least it was mild..

High pressure became temporarily central located on the 10th allowing the cloud to break up more widespread after a cloudy, misty morning. The day had long spells of unbroken sunshine across the country with outbreaks of sea fog along the east coast. This was the sunniest day of the month with up to 15.7 hours of sunshine at Johnstown Castle. Shannon Airport reached a high temperature of 26.2C.

The ridge of high pressure declined and pushed eastward on the 11th. After overnight mist and fog, the day brought hazy spells of sunshine but cloud and light rain arrived later from the west courtesy of an Atlantic front. The southerly airflow gave a very warm day to places, especially the Dublin area. Phoenix Park had a max temperature of 27.7C whilst Dublin Airport had its warmest day since August 1990 with 27.2C. Unusually, Casement was more than a degree cooler with 26.1C.

It didn't take long at all for ridging from the Azores to return by the 13th with good sunshine in the south and east at times. It was not completely dry with scattered showers in the north and west but it was mostly settled and fine with temperatures rising day by day.

By the 17th, the high pressure pushed eastward towards Denmark and Germany but still ridging towards Ireland with a very warm to hot southeasterly airflow developing. The max temperature on the 17th reached 29.3C at Phoenix Park, this was Dublin's highest temperature since July 2006 but higher was to come! Sunshine was very hazy from the high cloud but was widespread along with mid and upper 20s temperatures.

Then a historic day happened, the 18th July 2022. The airflow veered southerly rather than southeasterly as high pressure continued to vacate further eastward. This brought up an extreme hot airmass from Iberia with 850hPa temperatures as high as 24C in the south of Ireland according to reanalysis. This was by far the hottest airmass in recorded history over Ireland. The 20C isotherm has only paid Ireland a visit previously in June 2019 since 1959. The airmass was capable of breaking the Irish national temperature record set all the way back in June 1887 but as is normally the case with these kinds of setups, instability rises through the day with clouds and subsequently rain showers form limiting the potential for the temperature to skyrocket.

Much of the country woke up to relatively clear skies with some scattered high cloud here and there. It was generally cloudier towards the northwest with thick fog focused around the coasts of Connacht and Donegal. Temperatures were rocketing ahead from overnight lows around the mid-teens in the morning sunshine with low 20s seen for parts by 07 UTC. Phoenix Park achieved 25C by 09 UTC as the sun continued to shine and 29C at Casement by 10 UTC. However, showers were forming south of Dublin in the southerly flow and the temperature rises would slow down dramatically. Clearer periods occurred again a few hours later allowing temperatures to rise a bit more including to a record high of 33.0C at Phoenix Park breaking the previous national July record of 32.3C set in July 2006 and was the highest temperature in Ireland since 1887. That's a 135 years. This high broke the previous County Dublin record by a whole 2 degrees - 31.0C in August 1990 and July 2006. Numerous long-term station all-time records were set including Casement (31.9C compared to 31.0C in 2006), Dublin Airport (29.6C compared to 28.7C in 1990) and Mullingar (30.3C compared to 29.8C in 1949). The second highest temperature - 32.4C at Athy also bet the previous July record if the Phoenix Park value is considered suspect due to its sheltered location whilst it has been confirmed by the Met and is no longer provisional. Derrylin also recorded 31.2C which was the 2nd highest temperature on record in Northern Ireland behind only that of 31.3C set just a year ago in July 2021.

10 of the 25 synoptic stations achieved 30C or more on 18th July 2022 in Ireland. The current synoptic station network only goes back to 2011 which is not a long time in weather and climate records to compare to at all. 28th June 2018 had 5 of the 25 synoptic stations achieving 30C or more. It is likely that since at least 1995, such a day with widespread heat of this calibre hasn't been seen in Ireland. However, there is no way to directly compare pre-2011 as mentioned as the synoptic network was smaller then with different stations used.

Unlike July 2021, there were no tropical night conditions recorded anywhere in Ireland despite some modelling forecasts suggesting such and England having widespread tropical night conditions into the 19th including a record all-time high minimum temperature set. Values in Ireland all fell below the 20C threshold in the 09-09 UTC climatological day.

The hottest of the airmass got pushed eastward on the 19th as Atlantic lows neared our shores but Bunclody, Wexford still managed to achieve 30C making it the second day in a row and would not be the last of the summer either. The airmass allowed an extraordinary hot day in the UK with Scotland and England (Wales had set a record on the 18th too) records set including 40.3C. Before this day, the record was 38.7C from July 2019. 7 stations achieved 40C or more and 46 stations bet the July 2019 record indicating just how historic of a day this was.

There were outbreaks of scattered thunderstorms in the east of Ireland as the instability rose during the afternoon but for such a hot plume, it was rather benign and most of the UK had avoided thunderstorms with only the tip of Cornwall seeing overhead strikes. Photo is a lightning strike hitting the Poolbeg Chimneys from St. Vincent's Hospital on the 19th July 2022, it's a video still recorded by Roger McMorrow.

After the heat cleared eastward, most of the rest of the July was fairly changeable with a predominantly westerly flow, transient lows and highs. Whilst it was generally cooler, there was still warmth at times especially on the 23rd and 24th during a tropical maritime warm sector of low pressure.

That takes us into August 2022 which was a very fine month with well above average temperatures, vast majority on the dry side - some very dry - and much sunnier than average. In fact it was the warmest and sunniest August since 1995 nationally with mean temperatures as much as 2 degrees above the average in Cork. There was heatwave conditions in the second week of the month with long spells of unbroken sunshine widespread and record-breaking August temperatures set including a new national record which is still provisional as of writing this post. Roches Point had only 12.0mm of rain all month - its driest August on record, whilst most had their driest August since 2003. Shannon Airport had as much as 242.9 hours of sunshine - its sunniest August since 1995.

High pressure from the final day of July brought a fine start to most places for the August Bank Holiday Monday with good sunshine but was replaced by rain spreading northeastward from the southwest, heavy in places including Newport having a daily rainfall of 47.5mm. This rain turned more showery later with isolated thunder and ushered in quite a warm tropical maritime airmass with a max temperature of 26.0C at Oak Park the next day the 2nd. The next few days brought a mix of sunshine and scattered showers and it turned cooler from the northwest by the 4th but high pressure started to exert influence from the southwest.

Though scattered showers continued in the north at times, the high pressure arrived from the south through the weekend of the 6th and 7th cutting off the northwesterly flow and warming up with sunshine becoming more frequent.

The high pressure really made its move by the 9th over the country with unbroken sunshine nationwide for the next couple of days generally. Visibility was excellent and temperatures responded well to the sunshine. 30C was achieved somewhere in the country everyday from the 11th-14th with Oak Park seeing 31.7C on the 12th and Durrow 32.1C on the 13th. Kilkenny also seen 31.3C on the 12th - its record high for August. The former two broke the Irish national August record temperature from 1975 and 1995. It was the first time since 2003 30C has been achieved in the month of August in Ireland. This meant Ireland had 6 total 30C days in 2022 or 5 if you discount the outlier Bunclody on the 19th July. This is the most 30C days in any summer since 2013 (7 days) and the 3rd most since 1900 with 1995 having 10 30C days. However, these figures do not take account for station count changes over time so whilst it is indicative, it is not homogenous. What's also very notable is how summer 2022 recorded 32C in two individual months in Ireland in the same year, the only other time this has happened was back in 1976 with June and July. However, that was from the same heatwave spell whilst the 2022 ones were from two completely different periods of weather making it more impressive. 1976 and 1995 were the only other examples of 30C been achieved in 2 different months in the same year in Ireland. Again the 1976 one was from the same spell overlapping the calendar months whilst 1995 like 2022 was from individual spells, then it was late June and early/mid August.

The 18th July 2022, 13th August 2022 and 12th August 2022 all fit well within Ireland's warmest days of record in terms of absolute maximum temperature. 1976, 2006 and 2022 all have two days in the top 10 warmest.

Heatwave conditions were observed at 23 stations in the Republic and 4 in Northern Ireland though note that the UK Met Office uses 3 consecutive days to define a heatwave whilst Met Éireann is 5. For the sake of this, I'm going by the Met Éireann definition for Northern Ireland as well. This was the first August heatwave since 2003 with as much as 7 consecutive heatwave days at Ballincurrig.

All this talk of heat, the nights were actually relatively cool under the clear skies, light winds and dry soils following the dry July - in contrast to 2023. Mount Dillon rose from a minimum temperature of 4.0C to an afternoon high of 26.2C on the 10th. The relatively cool nights were why August 2022 was likely not as warm as some others and was cooler than July which had pretty warm nights under a lot of cloud cover.

Dublin Airport had its joint highest August daily sunshine total on record set on the 9th August with 14.5 hours. Malin Head with 14.6 hours on the 10th was the joint sunniest August day in Ireland with 1995.

Unrelated but the 11th August 2022 also brought an unusually late and bright noctilucent clouds display that was visible over Ireland with the clear skies. Usually, the last noctilucent clouds visible in Ireland are seen in late July. Also unusual how they occurred during a heatwave.

Instability increased as pressure lowered from the Bay of Biscay later on the 13th August and resulted in some spectacular thunderstorm activity with the west favoured on the 14th and the south on the 13th. Northeast Leinster and Dublin as well as parts of the Midlands mostly escaped from the thunderstorms. The thunderstorm thread has some brilliant photos from people here.

Following these thunderstorms, it became more changeable for a while but not wet by any means. Just cooler, more cloud around and some showers for the third week of August. There was still some good sunny, warmer days mixed in. It was far from a washout. The 21st was a very pleasant fine day in the east for example.

High pressure returned on the 27th building northward towards the Norwegian Sea by the 29th between Iceland and Norway drawing in an easterly flow. This was a significantly cooler high pressure than the one that brought the heatwave in the second week for the most part, especially on the east coast but there was still plenty of fine weather to be enjoyed. Durrow was up to 23C at 09 UTC on the 29th with an afternoon high of 26.4C, very warm given the airmass and the dry soils were certainly making a difference!

That concludes the look back on the summer of 2022. Though the season as a whole did not set any records in terms of averages or absolute totals, it certainly wasn't without its extremes or noteworthy aspects. Both July and August were very remarkable for their high temperatures, and Ireland finally got its warm, sunny and dry August it had long been waiting for since 2003.

There was a certain north-south divide to the summer of 2022 with a frequent influence of cloudy maritime airmasses to the north it seemed but the sunny August everywhere counteracted this to some extent.

I find summer 2022 very fascinating and it is one of my favourites to talk about for all the interest it provided statistically.

InAtFullBack

Superb summary. If three days or more of 30c could qualify as a hot spell, then five stations above met the criteria - Fethard, Kilkenny, Durrow, Oakpark and Athy for the August 2022 spell.

sryanbruen

How the September 2023 heatwave compares to the others in the Irish record, after updating the table I used for my summer 2022 post.

2021-23 is the first time Ireland has seen 3 consecutive years of heatwave conditions on record.

This is also the longest September heatwave of 6 days beating 5 days in 1959 & 1991.

sryanbruen

2023 started off with a mild, changeable first half to January followed by a dry second half. A bit of wintriness in the third week via an unusually cold polar maritime flow gave lying snow to places, especially in the south and parts of the north. See pics for credits, thanks to them for allowing me to share.

All photos were taken on 17th January.

1: Tory Island just off the northwest coast of Donegal with a rare dusting of snow. Credit Owen Clarke.

2: Sunrise over a snow covered Clonakilty, Co. Cork. Credit Michelle Mockler.

3: A frosty Killykeen Forest Park, Co. Cavan. Credit Orla Okeefe.

4: Snow covered Gougane Barra, Co. Cork. Credit Cian O'Regan.

-7.2C at Lullymore, Co. Kildare on 17th January is the lowest temperature of the year as of the data available in the Republic. This is a very unremarkable annual absolute minimum and continues the trend of failing to achieve -10C in Ireland since December 2010.

February was exceptionally dry - the 6th driest on record since 1941 which is a stark contrast on recent very unsettled Februaries - but also very mild (5th mildest since 1900) which seems unusual in a winter month but we've seen our share of mild, dry winter months.

March was a complete flip on February. It was extremely wet - in fact the wettest on national record and would be one of two months in 2023 to set a national rainfall record.

The second week of March contained some wintry weather with low pressure bumping into colder air on the 9th/10th bringing lying snow to places, particularly overnight. Did not last long in the March sun away from high ground where it took a few days to fully melt.

Photos are courtesy of SaveTheHellfire at the Hellfire Club, Dublin on 10th March and sarsfield06 at Cruagh Wood, Dublin Mountains also on 10th March.

April was largely benign and unsettled though did contain the first 20C of the year on the 16th which was a day early before the UK achieved their first 20C. This was the first time Ireland achieved the first 20C before the UK since 2010 and 3rd time since 1961.

Storm Noa, named by Météo-France brought storm force winds off the south coast on April 12th with 89 km/h sustained winds and 122 km/h wind gust at Sherkin Island but overall the storm was less notable in comparison to Storm Hannah from April 2019.

Curiously May was the 2nd warmest on record since 1900, this in spite of achieving no exceptionally high temperatures. The highest temperature was 24.9C at Shannon Airport on the 30th amidst what would become an exceptional prolonged spell of consecutive 20C days to 24th June. This is probably the longest spell of unbroken 20C days since the summer of 1995 at an individual station (Athenry also did this) and the fact it occurred so early in the season makes it even more exceptional in my opinion.

Mid-May to mid-June 2023 was exceptionally dry with absolute drought conditions recorded. Dublin Airport had its longest absolute drought since 1955 (26 days).

June 2023 featured 8 consecutive days of thunderstorms across Ireland from the 13th-20th. I haven't seen a period of consecutive thunder days like this before in Ireland. There was also further thunderstorms on the 25th. 17th and 20th especially widespread.

June 2023 was by far the warmest June on record in Ireland with almost all stations smashing previous warm June records including 1940, 1976 and 2018, aside from some Dublin stations where it was the warmest since 1976. First time the national June tmean was above 16C.

Another record-breaking aspect of June 2023 that also warrants mention is the marine heatwave in the North Atlantic. M5 buoy SST of 19.7C would be exceptional in the heart of summer, in June it's extreme.

All the warm June and absolute drought conditions would become a long distant memory with an extremely wet July following. The wettest July on record in fact - the second month this year to do so and the first time that 2 wet records have been set in the same year.

The unsettled summer would continue into August though not a write off deluge like July, it still had very wet weather. Most notably it contained named storms Antoni and Betty. Antoni produced flooding rain in the north whilst Betty in the south.

Betty on the 18th especially was exceptionally wet with daily falls for widespread parts of the south in excess of 50mm including Valentia Observatory 74.0mm (wettest August day since 1986), Cork Airport 63.0mm (wettest August day since 1998) and Roches Point 59.6mm.

It should also be noted that Valentia's daily fall from Betty included an hourly fall of 36.2mm, its highest on record.

September began with a rare heatwave - only the third official September heatwave on Irish records (1959, 1991, 2023). Lullymore recorded a max temp of 29.1C on 8th September - equal highest Sep temp on Irish record with 1906. Lots of station records set.

This also meant Ireland had official heatwave conditions 3 years in a row which has not happened before (July 2021, August 2022, September 2023).

September was also the 3rd warmest on record since 1900. 2021 was the warmest September.

The first half of October brought yet more notable warmth, this time more focused on eastern areas as there was a lot of cloud with the high pressure system mostly to the southeast. Dublin Airport had its highest October temp on record on the 9th, record beaten by a whole 2 degrees.

Dublin also had 5 consecutive days of 20C+ from the 6th-10th October.

Not confirmed but Ashford had a provisional 24.0C on 7th October - highest for October in Ireland since 1969 (including Northern Ireland) if confirmed.

After a dry first half, October turned exceptionally wet in the second half with Storm Babet especially giving a soaker to the south of Ireland. Cork Airport had 146.8mm fall within 4 days from the 17th-20th. It became the wettest October on record there too.

The closing months of 2023 have tended to be more benign but December likely to be one of the mildest - probably not as mild as 2018 or 2015.

2023 is by far the warmest year on record for Ireland, 2nd year in a row to do so.

Thank you for reading.

InAtFullBack

Great summary there @sryanbruen though in 2018, there was a -12.1c recorded at Johnstown in Kilkenny on a VP2:

sryanbruen

https://www.boards.ie/discussion/comment/121571981#Comment_121571981

That is not an official station. I only discuss official Met stations here.

Kilkenny's official lowest temp in 2018 was -5.5C at Greenshill on March 1st.

sryanbruen

With some possibilities (but far far from any certainty) of a cold and wintry second half to February, I thought it would be the perfect occasion to do a post on the textbook cold and wintry February second fortnight of 1955 which I don't believe I've done before.

Before I get into February, I should mention that January 1955 was also a cold month but ended on the mild side and December 1954 was mild with some exceptional wet weather including a historic flood in Dublin that I've posted about before.

The milder, more changeable weather from late January continued into early February 1955 with a washing machine of areas of low pressure circulating around the North Atlantic. However, the jet stream was on a very southerly track dipping down to Algeria. It wasn't especially mild but it was milder than what the month would provide later on. Temperatures by day were in the upper single figures or touching low double digits and nights were rather cool when the flow would become more slack in the cyclonic polar maritime air.

The 7th was quite a mild day, the mildest of the month generally with up to 13.0C at Birr.

By the 9th, heights rose over Greenland and Iceland. This forced the Atlantic low pressure systems eastward and any further ones would undercut to the mid Atlantic. The winds veered northerly and northeasterly by the 12th drawing in a proper cold airmass with the -7C isotherm clearing the country. There were snow showers but not all that heavy or as widespread at this point, there was plenty of crisp winter sunshine however.

Ireland had a near miss snow event via a mini low pushing south on Valentine's Day which brought in a renewed northeasterly flow after as blocking remained strong to the northwest. Still rather light scattered wintry showers at this point and more crisp winter sunshine with harsh frosts at night.

On the 16th, the coldest air of the month and winter would arrive. Heights really lowered to the east and the blocking retrogressed further northward into Greenland. This brought down a proper northerly blast to Ireland feeding in widespread snow showers. The north got pummelled at first with gale force northerly winds in the northeast of Scotland. I don't have wind data for Malin Head as this month predates the available data in the public domain there. The snow data is also scarce.

On the 18th, the trough to the east sank south and brought in more of an easterly wind bringing the significant risk to more eastern counties. This would be the first of 10 consecutive days where Dublin Airport reported snow lying at 9am - exceptional for this late.

The snow showers continued to pile in for days as easterly winds remained. Low pressure to the south brought a huge snowstorm to southwest England at this point. Note the blocking has nearly all disappeared though a weak ridge over Iceland remains, just enough force to allow the cold to continue across us. Dublin Airport had a depth of 13cm of snow at 9am on the 22nd.

Meanwhile, further north winds were calmer and it was severely cold under clear skies at night. Markree Castle got down to -12.8C early on the 21st and included 6 consecutive days of minima -5C or under. Claremorris had -11.0C on the 20th and didn't get above -1.9C all day under freezing fog. Markree Castle similarly didn't get above -2.2C on the 20th.

Even by the 24th, easterly winds were still blowing as heights rose over Scandinavia. Dublin Airport reported a renewed snow depth of 13cm again at 9am on the 25th.

The easterly winds finally abated by the final day and some milder air started to filter up from the southwest as pressure dramatically lowered over Iceland but that was quite a cold spell lasting from the 10th-27th February pretty much, that's 18 days long. It's a shame there's not a lot of data to go off of for this month and I currently do not have access to the newspaper archive.

sryanbruen

Interesting data on number of thunder days per year for a few Irish stations. Seems to have been a slight decrease over time with the 2010s decade quite lacking in thunder days. 2023 bucked the trend somewhat.

Most thundery years based on this data

2008 9 days

2000 8 days

1982 8 days

1995 8 days

2014 7 days*

Least thundery years

2021 2 days*

2018 2 days*

2011 2 days

1988 3 days

1993 3 days

*Belmullet data not available.

sryanbruen

Interesting to see a different spin on my usual Irish rainfall stats I share - this one is running 10-day averages since August 2019 with different periods noted.

7th June 2023 was the last time the 10-day average was at 0mm. 18th January was the last time it was under 1mm.

Wettest days on this daily series (goes back to 2009)

5th Dec 2015 32.7mm (Storm Desmond)
19th Nov 2009 30.4mm (infamous Cork flood)
6th Sep 2010 29.8mm
1st Nov 2009 23.5mm
23rd Oct 2011 21.8mm
6th Nov 2014 20.7mm
12th Dec 2015 20.0mm
13th Nov 2014 20.0mm

Wettest day per month

31st Jan 2014 17.4mm
9th Feb 2020 19.5mm
29th Mar 2010 16.6mm
6th Apr 2010 13.7mm
20th May 2021 15.4mm
7th Jun 2012 19.9mm
10th Jul 2010 19.3mm
2nd Aug 2014 19.2mm
6th Sep 2010 29.8mm
23rd Oct 2011 21.8mm
19th Nov 2009 30.4mm
5th Dec 2015 32.7mm

Pretty interesting how despite being quite a dry year (the driest year in the series), 2010 has 4 of the 12 months' wettest days. Only other year with more than one is 2014 which has 2.

Elmer Blooker

https://www.boards.ie/discussion/comment/103362799#Comment_103362799

I was thinking of the very warm Easter or ‘the perfect Easter’ as described above exactly 40 years ago. I knew I’d find something and after a quick search I found this.
The benefits of a late Easter or in 1984 a very late Easter.

sryanbruen

https://www.boards.ie/discussion/comment/122038506#Comment_122038506

Easter 2019 although started off on the hazy side with some bad air pollution via southeasterly winds limiting the temperature became very warm, record-breakingly so in Dublin, by Easter Saturday the 20th April. 21st April 2019 (Easter Sunday) holds Dublin's highest April temperature on record with 23.1C. That's lower than the county's March record of 23.6C from Trinity College in March 1965!

Dublin Airport had 2 consecutive 20C days on April 20th/21st 2019, exceptional for there this time of year (sounds very dismal but it's true). Easter Sunday was its first April 21C on record too.

That's my modern perfect Easter though do remember being very disappointed by those first few days before Easter Saturday came and it was a distant memory.

sryanbruen

There's a lot of misconceptions and false memories of how the May/June period of 2023 evolved weather wise. This post is going to analyse the period and hopefully put all of the false memories to rest.

I have already shared a few of the stat related images in my 2023 extremes analysis above but including them here again for this one as they are relevant.

The start of May 2023 was very benign with ridging through the country giving a lot of dry weather but skies were rather milky and temperatures not all that far from average though rising in the upper teens in any sunshine. At times, there was light rain or showers near the west coast.

Low pressure in the Atlantic approached Ireland by the 5th leading to sunshine and showers, some involving thunder. It was fairly warm for early May with nearing 20C in sheltered eastern areas from the southerly flow. It was quite a blustery southerly wind reaching gale force at Malin Head. This low would fill and winds would calm down for the next few days. The weekend of the 6th/7th started off with sunshine and scattered showers whilst the 7th transitioned from a dry start with sunny spells followed by rain approaching from the west later. Temperatures continued to be rather above average in the upper teens.

Another depression made its way towards Iceland on the 7th into the 8th bottoming out at 978mb. A showery day followed with unusually intense thunderstorm activity taking place in the late afternoon to evening hours in the east. Rather warm in the sunshine earlier in the day reaching 20.2C at the Phoenix Park.

More showers involving thunderstorms occurred on the 9th but not nearly as intense and fresher Atlantic air was coming in behind fronts.

By this stage, although temperatures have hardly been dramatic in any way - just barely reached 20C on the 8th in Dublin - mean temperatures for the month of May were exceptionally high thanks to persistence of daytime temperatures in the mid to upper teens and night time temperatures have been well above average under a mild airmass.

After a few showery and cooler days, the Azores High sent a ridge in Ireland's direction from the 12th. To less or better extent, this would become the prime dominance for a good month. The May/June dry spell started around this point, statistically on the 15th. At times, weak fronts approached from the west giving light rain such as on the 14th, 20th and 21st but on the whole, it was very dry. It wasn't wall to wall sunshine, at least for a while. Temperatures were variable but unremarkable ranging in the mid to upper teens and occasionally touching 20C until the 26th.

From the 26th, a large anticyclone exerted its influence strongly across Ireland with temperatures in the low 20s for sheltered western areas and midlands. Sunshine became more prolonged and widespread. As winds later veered easterly, it tended to be cooler in the east and it struggled to reach anything better than upper teens on the east coast. Meanwhile, Shannon Airport achieved 24.9C on the 30th but this is not a remarkable value. Nonetheless, the 29th May would be the beginning of an exceptional spell of consecutive days of 20C for stations like Shannon Airport and Athenry which would last until the 24th June. Such a spell of consecutive temperatures at individual stations has not been seen in Ireland since summer 1995.

The anticyclone adjusted itself to the northwest of Ireland by the final day of May into early June bringing in more of a cooler northeasterly flow. This meant temperatures were even more suppressed along eastern coasts not getting any better than mid-teens. Further inland though 20C was easily achieved in any sunshine and it was up to 25C in sheltered western areas.

The northeasterly flow also brought in low cloud off the Irish Sea to the east coast during the middle of the day from the 31st May-2nd June which added a further barrier to allowing the temperature to rise here. The cloud broke up during the evenings with widespread clear skies nationwide.

The high pressure built more over the country for the June Bank Holiday Weekend from the 3rd-5th cutting off the northeasterly flow. This meant there wasn't as much of a cooling airflow for eastern areas and there would be no low cloud approaching from the sea. There was widespread unbroken sunshine for each of the days. Nights were rather cool under light winds and clear skies. 25C continued to be achieved in the west with up to 26.5C at Ardfert on the 5th. It was a bit breezier at times on the south coast but it was near calm for much of the period.

The ridge weakened on the 6th building back again further northward allowing the northeasterly flow to return decreasing the temperature for eastern coasts. The 6th was quite a cool day here under persistent low cloud during the middle of the day but again like the 31st May-2nd June, it broke up during the evening with sunshine returning. Otherwise, it was much the same with good sunshine for a lot of the country and warmth continuing in the west.

The 7th was very similar to the 6th but not as warm as it had been for a week in the west.

Pressure continued to lower and the anticyclone developed more towards Scandinavia by the 10th. Initially, it continued dry with sunny spells and warmer again especially in the west but showers ended the absolute drought period for much of Ireland on the 10th. Dublin Airport had its longest absolute drought (15 consecutive days+ of less than 0.2mm) since 1955 with 26 days from 15th May-9th June 2023. Phoenix Park had its longest absolute drought on record. Ireland hadn't seen as persistent a dry spell since 2018 which is remarkable considering how wet 2023 would end up being as a year and in general how wet it has been since September 2022.

However whilst it was the end of the statistical drought, by no means was it a return to the norm or Atlantic dominated deluge conditions. In fact, it remained mostly dry for a while but there was intense thunderstorm activity in places which I will get into.

Up to this point in time, there was a significant contrast in average temperature across Ireland. Parts of the west were exceptionally warm with mean temperatures as much as 3-5C above average. In contrast with all the easterly to northeasterly winds, the east was much cooler and in fact it was nearly a degree below average for the Dublin area.

The Scandinavian high exerted its influence westward towards Ireland on the 13th. A very warm airmass was brought in via this airflow leading to the warmest day of the year up there with 8th September. The air temperature reached as much as 28.8C at Oak Park which is the earliest on record for a temperature this high. 29C was achieved provisionally at Bunclody (Wexford) and Dundalk (Louth) but the Dundalk value of 29.7C was disregarded and no update on the Bunclody value has been given. It was an exceptionally warm day for this early in the summer season. The combination of dry soils and an ideal pattern were perfect for skyrocketing temperatures in Ireland, if it were slightly later in the season… 30C probably would have been easily achieved.

The 14th/15th were also notably warm days with Athy (Kildare) seeing 28.1C on the 15th and Durrow (Laois) as well as Glenties Hatchery (Donegal) seeing 28.0C on the 14th.

Newport (Mayo) had 5 consecutive days where the temperature did not fall below 15C, truly remarkable for June.

Thunderstorms occurred in various parts of the country later in the day. This would become the first of 8 consecutive thunder days in Ireland - such a persistent period of thunder activity has likely not been seen before in Ireland in modern reliable records.

The other thing to note at this point is with all this persistence of high pressure and huge solar radiation into the North Atlantic, sea temperatures were at an all-time high. The values seen would be exceptional for the heart of summer.

The ridge declined by the 16th with more cloud around and very intense thunderstorms occurring on the 17th and 20th. 27mm of rain fell within 30 minutes at Killarney on the 20th. This was when it started to be more changeable but only gradually. A few days of scattered showers afterwards with high pressure building to the east bringing more of a southwesterly to southerly flow by the 23rd. All the while, it continued to be on the warm side touching the low to mid 20s.

Thunderstorms returned on the 25th with significant hail reported in the southeast including a couple of cm covering in Enniscorthy (Wexford). What a month June 2023 was for thunderstorms in Ireland.

The final week of June was changeable with sunshine and showers generally speaking. Temperatures still on the rather warm side but cooling down through the final two days and more persistent rain on the 30th as the Atlantic finally broke through but until early September, that was the end of the warm, summery weather.

June 2023 ended as by far the warmest June on record across Ireland. Only the Phoenix Park and Dublin Airport failed to be the warmest on record where here it was the warmest since 1976 - likely due to how cool the early month was before the warmth finally arrived here too on the 11th.

Mean maxima were comparable to an above average July and an average June is nearly 2C cooler than the average July. They were also not worlds above the average maxima of June 2018 but June 2023 had significantly warmer nights than 2018. I don't have much information on June 1940 which was the previous warmest June on record for the nation.

May ended on the sunny side but overall wasn't anything notable sunshine wise. June meanwhile had good sunshine a fair bit of the time once intense thunderstorm activity wasn't ongoing or low cloud coming in off the sea to eastern and southern areas. It was the sunniest June since 2009 at Malin Head with 251.8 hrs of sunshine. Many had their sunniest June since 2018.

I hope this look back has refreshed the memory banks and there will be no more false recollections of May/June 2023.

Thanks for reading.

sryanbruen

This post will be discussing the summer of 1989 which was one of the most forgotten but greatest Irish summers of all-time if it's warmth and dry you seek.

The summer pattern began in May 1989 following a cold April. The first day of May and we can already see a classic summer pattern signature with no sign of Greenland or Iceland blocking, indicative of a +NAO. Azores high ridging up from the southwest into the UK. Ireland not quite feeling the effects yet with a cloudy and humid southwesterly flow but the cold April was a distant memory.

High pressure started building in the days afterwards leading to the first warm weather of the month and "summer". 22.3C was recorded at Ardfert (Kerry) on the 6th and 22.1C at Lanesboro (Longford) on the 7th. Nothing exceptional but pretty warm for this early on. A period of cooler weather followed as ridging retrogressed westward up to the 13th. Even the best Mays and summers have periods like this.

Ridging built back up from the south on the 16th and would come and go for the rest of the month with a strong influence leading to an increase in temperatures. It would become exceptionally warm for the time of year by the 22nd.

On the 18th before the warm spell got really going, a trough between two high pressure centres became slow-moving over Ireland leading to thunderstorms. 13.3mm of rain fell in an hour at Casement.

Southeasterly winds and high pressure over Scandinavia ushered in very high temperatures for May across Ireland on the 22nd and 23rd. It was much cooler on the east coast in the upper teens. Unusually Valentia (Kerry) had the highest temperature in the country with a max of 26.9C on the 22nd. This would stand as its record high May temperature until 1997. This was the highest May temperature anywhere in the country since 1922. It became relatively cooler after the 23rd but until the final few days, 20C was still achieved on a significant scale. It was not quite the warmest May on record but was way up there - Valentia had its highest May mean maximum on record and warmest mean since 1893.

Isolated thunderstorms occurred. Overall, May was an extremely dry month across the bulk of Ireland. It was the driest May on record for Rosslare (Wexford), Cork Airport and Dublin Airport which escaped the thundery rain on the 18th. Rosslare had just 6.0mm of rain all month and Cork Airport had 8.4mm.

May was also very sunny with almost all stations exceeding 200 hrs with the exception of Birr. Totals were as high as 251.2 hrs at Roches Point (Cork). No records were set however.

A big change happened in the final days of May 1989 with high pressure retrogressing westward allowing a cool northerly flow to develop. It continued to be on the dry side but temperatures were very suppressed. Maxima up north were just around 10C by day including only 10.0C at Ballyshannon (Donegal) on the 31st. There was also air frost at night locally including -1.5C at Naas (Kildare) with harsh grass frost, as low as -8.2C at Lanesboro.

So one of the warmest Mays on record ends on a decidedly cold note. Classic weather flips which can and always will happen.

That takes us nicely into June 1989 which was a month of contrasts. The first 10 days were very cool. Average temperatures were a good 3-4C below average. For example, Clones (Monaghan) had a mean temperature of 9.6C by the 8th which is 3.3C below its 61-90 average. This was all brought about by a persistent northerly flow as high pressure always stayed out to the west. Letterkenny (Donegal) reportedly had an air frost of -0.1C on the 8th, not too sure about that but the airmass was cold and slack. Malin Head had a min temp of 2.6C on this same day, its lowest June temp since 1955. Casement had a min temp of 0.7C on the 1st, its lowest for June since 1975. The daily max temp was just 10.2C at Clones and 10.6C at Naas on the 2nd.

A change occurred by the 10th with a southerly flow as high pressure to our west was replaced by low pressure. It took a few days for temperatures to recover though to above average values. This period was very wet in places with slow-moving fronts including 39.3mm at Claremorris (Mayo) on the 9th.

On the 16th June, a strong ridge of high pressure intensified as it developed over Ireland giving widespread sunshine and well above average temperatures. In fact, they were exceptionally high. Something strange was going to occur - none of the Republic of Ireland achieved 30C from this period but Northern Ireland did. Armagh achieved 30.0C on the 19th before a quick cool down. This wouldn't be the only occasion of 30C anywhere on the island this summer. Many had highs in the 27-29C range on the 18th and 19th June including 28.6C at Birr (Offaly), 28.5C at Shannon Apt (Clare) and 28.1C at Kilkenny. Even the east coast was well into the 20s minus the SE corner.

Between the 14th and 24th June, Rosslare had more than 10 hrs of sunshine each day.

As high pressure weakened and retrogressed westward, the rest of June was cooler and more changeable. Was this the sign of the times? Was the summer on life support now? Was May and that short mid-June warm period the best the summer had to offer? Nope. In fact the best was still to come and records were going to be broken.

Two days into July and already high pressure is building from the Azores as the jet stream gets shoved northward. This high pressure would be a strong influence through most of July bringing an exceptionally warm, dry and sunny month.

At the time, this traded blows with July 1983 as the warmest month on record depending on the location. The daytime temperatures were sustained in the 20s day after day after day resulting in mean maximum temperatures that were between 3-5C above the relevant average. Kilkenny had a mean maximum temp of 24.0C with 20C achieved here every day between the 2nd and 30th and 13 of these were above 25C. Even Dublin Apt had a streak of consecutive 20C days of 21 days, its longest ever on record and still is to present.

The highest temperature of the month was 30.5C at Lanesboro on 19th July. Shannon Apt had 30.0C on the 18th. Roches Point's max of 27.5C on the 15th was its highest on record. Minimums were also exceptionally high at times. This month features the highest of any minimum temperature on record with 20.9C at Derrygreenagh (Offaly) on the 25th July. This was only one of 7 tropical nights (a min temp >20C during the climatological day of 09-09 UTC) on record in Ireland. Whilst not a tropical night, Naas had a min of 19.3C on the 22nd July.. I'll remind this same station had -1.5C on the 31st May.

The month was very dry - the driest July on record at Birr where records go back to 1872 with 12.8mm of rain falling during July. Only 6.9mm fell all month at Kilkenny and 9.6mm at Dublin Apt. It was the driest July for other places since 1982, 1983 or 1984. The exceptionally dry, sunny and warm May and July 1989 gave rise to very high soil moisture deficits with as much as nearly 100mm at Oak Park through July. It's a miracle how a hosepipe ban wasn't issued or at least not from what I've been able to see but nonetheless, I'd say the water supply was being rationed in some places. Gorse fires were frequent.

To finish off the fine statistics of July 1989 and already hinted at, July was very sunny. With the exception of Clones however, it wasn't as sunny as July 1955. Clones had 252.2 hrs of sun making it the sunniest July on record here and the sunniest month until August 1995. It was cloudier at times in the north with 159.6 hrs at Belmullet and 163.8 hrs at Malin Head through July though these are still above average. Roches Point was the sunniest station through July with 264.8 hrs.

May-July 1989 was one of the sunniest of any tri-monthly period on record in Ireland. Numerous stations had exceeded 200+ hrs of sunshine in each of these months. Roches Point had 753.9 hrs of sun during this period, an average of 8.2 hrs of sun per day. Probably the sunniest of any period in Ireland since Rosslare's exceptionally sunny summer in 1959.

There wasn't much in the way of thunderstorms during July with it being mostly anticyclonic and very dry. However, thunder did occur in the south on the 7th as a low pushed westward from the continent.

High pressure wasn't often centred right over Ireland, rather it varied in position through the course of the month - sometimes being just to the west but having enough influence to keep it very warm, right over home or to the east drawing in warm southerly or southeasterly winds.

Compared to recent months, August 1989 was unsettled and rather mild instead of very warm to hot. The first few days had weak high pressure still hanging on by its finger tips before an active cold front spread south on the 5th bringing thunderstorms. This set the scene for the month with westerlies dominating. As a result, it was rather wet for most bringing an end to the very dry weather that had been frequent since May but there had been wetter Augusts in the 1980s - most notably 1985 and 1986. Perhaps a bit unusually despite the month being westerly, it was quite humid with a sticky feel to the weather evident during a lot of the period. This is what the Met mentions at least, I don't note anything outstanding for average dew points and relative humidity from the stats.

The highest temperature of the month was early on with 24.4C at Casement on the 3rd.

More than half the month contained gale force winds at Belmullet (16 days) and Malin Head (20 days). This synoptic showing deep low pressure just out to the west of Ireland was typical.

That's a wrap on the summer of 1989 which for quite a dry and very warm summer sure had its mix of fortunes. September was back to the dry theme but cloudy and cooler compared to the summer months and May.