Summer 2018 - General Discussion

km79

Elmer Blooker wrote: »

I'd prefer summer in July and August. A very long dry spell ahead which means that July and August will be wet, that's not a prediction, it's just an opinion.
I've always had my doubts about summers that are early starters.

I 100% agree so intend to make the most of it

mg1982

Here in the north west we always seem to get our best weather late spring early summer, July and August tend to be dull damp months.

sryanbruen

mg1982 wrote: »

Here in the north west we always seem to get our best weather late spring early summer, July and August tend to be dull damp months.

There's a reason why that is so. See MT's descriptive post below but basically the reason is that May is the most easterly month of the year on average. In easterlies (as perfectly shown by May 2017, a recent example), we can achieve a lot of sunshine here whilst England and Wales tend to be duller exposed to the easterly wind and dragging in a lot of cloud off the North Sea which tends to still try to warm up at that time of year. However, as we get to July usually, the westerlies begin to intensify and push the sunniest of the weather into England and Wales where July is normally their sunniest month of the year. Of course, this isn't always the case and in fact, July can set records for sunshine as it did in 1955 with July 1955 being Ireland's sunniest month.

https://www.boards.ie/vbulletin/showthread.php?t=2057744388

sryanbruen

I have not looked at Summers following warm and dry Mays on their own (w/o considering March and April in the equation) yet so this is what I'm doing today here. The picture is very bleak for Summer just like most of these analogues but this time, the jet stream is coming from a northerly track instead of a southerly track so cold and wet.



Now, let's look in a little deeper to the actual May pattern combined with the warm and dry nature. I've crawled through the archives to find a May with a pattern similar to 2018. This is May 2018's 500mb height anomaly reanalysis up to the 17th with the jet stream to the north and a big ridge of high pressure across the Atlantic, through us and going into Europe; a classic positive NAO setup but with the jet stream to the north, it's been generally settled.

I found two similar matches to the May 2018 pattern, one of which is not a dry May but warm; 2009, and the other is 1989 which of course was an excellent May followed by a very good Summer in comparison to 2009 which was the "BBQ" Summer disaster that the UK Met Office forecasted. There was also 2003 that was quite close but the trough is more over Ireland than way to the north which led to May 2003 being an unsettled month and fairly mild.



2009



1989



2003



2009 whilst being a washout Summer overall and in fact, the wettest Summer on record in places including Valentia Observatory where records go back before 1900, was quite warm and June had some reasonable fine conditions at times. It was also the sunniest June since 2006 at this time and for others, the sunniest June since 1959. July though again very wet was a sunny month with close to normal temperatures and August was a warm month with quite a northwest-southeast divide. The northwest was very wet in nature and the southwest too but the southeast had close to average rainfall and sunny conditions.

1989 had a mixed June with a very warm spell mid-month. July was very warm with sustained high temperatures for a long period of time, very sunny and dry too. August was a warm but changeable month. This all coming after a very warm, dry and sunny May.

June/July 2003 were largely unsettled with a lot of thunder at times but very warm too. July was quite dull. Meanwhile, August was very anticyclonic, warm and sunny. This was the last August to be this way up to the current moment when I'm doing this post in 2018 with every other August since missing out on one of the elements. To give the warm Augusts since 2003 as examples: The following August in 2004 whilst very warm was exceptionally wet with some severe flooding in parts of the east. 2005 was a fairly changeable month all around. August 2006 was dull. August 2009 as you know from above had a northwest-southeast kind of divide. August 2012 was very wet for the south. August 2013 was dull. August 2016 was close to average sunshine and rainfall. As you can see, we've had quite a long run of poor Augusts that you'd think we're overdue for a classic or at least decent one (though I loved August 2016 personally).

So, what we can gather from this is that warm and dry Mays combined on their own are a mixed bag for the Summer. The analogue contains years we've looked at plentiful times this season; 2008, 2001, 1911, 1959. From a May 2018-like pattern stand point, we can say that there is agreement for a warmer than average Summer but a divide on rainfall. I'll be bringing everything together in a week on Tuesday (May 29th).

sryanbruen

Very 2003-like here! We just looked at 2003 earlier, what a coincidence.

https://twitter.com/TWOweather/status/998242229406830592

sryanbruen

Latest CFSv2 shows hints for a very easterly to southeasterly June with a continuation of the Scandi High.

arctictree

Really needed some rain here in the east last couple of days but got very little. Ground is bone dry. Now a week of dry weather is forecast. Not great for farmers trying to get some growth.

sryanbruen

If it's any consolation, late May 1947 brought temps into the 30s in the UK (preceded by the big freeze from January to March that year with several blizzard events) and this was followed by a hot, humid and thundery Summer with the best Summer month of the century at that point. August 1947 was an absolute gorgeous month with lots of hot easterlies. Very sunny, very warm and dry. I go into detail on August 1947 here: https://www.boards.ie/vbulletin/showpost.php?p=106736294&postcount=421

If you have been keeping up to date with me, you know that 1947 is one of the years that has been appearing the most in my Summer 2018 analogues.

sryanbruen

The UKMO Glosea5 model has upgraded the warmth for Summer 2018 now. Quite a significantly warmer than average season being signalled at by the model for much of Europe though Ireland is more closer to average whilst still being warm. Precipitation coming out as below average. Keep in mind, this is a 3 month anomaly so you can have monthly deviations.

sryanbruen

It's not often that I look at the Beijing Climate Centre model but currently, they're showing a classic Summer scenario for 2018 with lots of stubborn high pressure bringing warm and dry conditions. Nice to look at. With the pressure and precipitation distribution, definitely underestimating the temperatures. Screams July 2013 to me in some ways.

nacho libre

Mother of God it's muggy now- 95 per cent humidity at the moment. Just a couple of months ago my hands would freeze if exposed to the air for a minute

sryanbruen

Latest CFSv2 update for Summer 2018 is showing a very easterly dominated season. Easterlies in Summer of course lead to very warm to hot weather. June looks to be very settled and warm. July looks to be settled and relatively warm, perhaps not hot due to the high pressure centre being in the centre of the Atlantic (though it does ridge to Ireland). August is interesting. It shows quite a Scandi High here on the model pulling up some very warm air from Europe. There are no heights over Ireland suggesting there is some sort of trough here which combined with the warm air can only mean one thing, thunderstorms! August could be quite a thundery month if the CFSv2 is right, this is not the first time an August of such has been suggested (see my analogues with at least 5 of the elements). If the CFSv2 is correct, we'll be in for a very warm Summer.

sryanbruen

Hang on, it appears that I have not done an analogue on Summers following on from cold Februaries. Could have sworn I already did.

Here is the analogue anyway. For a February to be qualified, it must be similarly cold in depth to 2018, around 1 degree below average. The CET for February 2018 was 2.9c. So 1947 was the coldest February on record with a CET of -1.9c, this is not qualified as it's far far colder than 2018 (though 1947 is one of the years that has been appearing the most).

Again, it's not a pretty picture just like most of the analogues. Very cool and unsettled pattern.



If we were to take out years pre-1950, the low is less deep and further to the east with high pressure closer to Ireland. A more settled chart but nevertheless, still very cool. Cool and dry in Summer is quite an unusual combination just like mild and dry in Winter.



In this analogue, two of our most frequent years appear again, 2013 and 1996. 1970 has 5 elements now so is going to be considered as one of the years for my final Summer analogues and forecast. 1989 also.

sryanbruen

On a somewhat unrelated note to this tweet, 1934.... one of the years that has been cropping up the most in my analogues this year for Summer 2018. July 1934 was a hot month. May 1934 was also warm and sunny with very dry conditions to the south. June 1934 was dry and warm as was September 1934. 1934 was in the cusp of solar minimum. The end of February 1934 brought a cold northerly into March and the lowest temperature of the year fell in March. April was a dull and unsettled month then.

Seeing a trend here?

https://twitter.com/BigJoeBastardi/status/1001215352901120001

Artane2002

sryanbruen wrote: »

On a somewhat unrelated note to this tweet, 1934.... one of the years that has been cropping up the most in my analogues this year for Summer 2018. July 1934 was a hot month. May 1934 was also warm and sunny with very dry conditions to the south. June 1934 was dry and warm as was September 1934. 1934 was in the cusp of solar minimum. The end of February 1934 brought a cold northerly into March and the lowest temperature of the year fell in March. April was a dull and unsettled month then.

Seeing a trend here?

https://twitter.com/BigJoeBastardi/status/1001215352901120001

Getting a bit ahead of myself but by any chance do you know how Winter 1934-35 went?

sryanbruen

Artane2002 wrote: »

Getting a bit ahead of myself but by any chance do you know how Winter 1934-35 went?

The mildest December of the century though still way below that of December 2015's phenomenal warmth. A very dry January but mostly mild with some snow towards the end of the month. Ireland had 45% of its average January rainfall according to the UK Met Office, doesn't say Northern in the name. February was a very mild month too and mainly wet. You definitely don't want Winter 2018-19 to go the 1934-35 way. :P

I can see two different possible solutions for Summer and I will be discussing this either tomorrow morning (depending on my mood) or tomorrow evening in my forecast for the season. Most likely tomorrow evening after my exam. Both solutions provide a good outlook for June whilst there's a division on July and August.

Artane2002

sryanbruen wrote: »

The mildest December of the century though still way below that of December 2015's phenomenal warmth. A very dry January but mostly mild with some snow towards the end of the month. Ireland had 45% of its average January rainfall according to the UK Met Office, doesn't say Northern in the name. February was a very mild month too and mainly wet. You definitely don't want Winter 2018-19 to go the 1934-35 way. :P

I can see two different possible solutions for Summer and I will be discussing this either tomorrow morning (depending on my mood) or tomorrow evening in my forecast for the season. Most likely tomorrow evening after my exam. Both solutions provide a good outlook for June whilst there's a division on July and August.

That sounds like a disaster of a winter! Like a combination of 2015-16 and 2016-17.

I can't wait to see your thoughts on the summer. I'd take a poor summer if I'm guaranteed an excellent winter to be honest.

sryanbruen

Artane2002 wrote: »

That sounds like a disaster of a winter! Like a combination of 2015-16 and 2016-17.

I can't wait to see your thoughts on the summer. I'd take a poor summer if I'm guaranteed an excellent winter to be honest.

It was a disaster of a Winter. If it would take place in modern times, enthusiasts would be crying and ripping their hairs out in anger. See December 1934's reanalysis for example. Stubborn northern blocking but the deep trough is just north enough to give us a very mild and wet month. We were extremely unlucky. I get some Winter 2013-14 vibes from this chart.



I'd rather both a hot Summer and a cold Winter. Summer 1995 - the classic that I just posted about today in the statistics thread - was followed by the coldest Winter of the 90s (not really saying much in the grand scheme of things considering the 90s) including a cold December and a cold, wet and snowy February with much of January being very mild and dull though it ended on a very cold easterly. The end of December 1995 brought temperatures as low as -27.2c in Scotland and I think -11c in Ireland.

Summer 1934 was a weird Summer with a lot of northern blocking (just like December 1934, probably courtesy of low solar activity) but July just happened to be a warm month.

Kermit.de.frog

Muggy and humid tonight, not the most comfortable for sleeping.


At least I have my trusty fan to keep me company.

sryanbruen

Ok well, I'm up earlier than intended so I guess I better get on with the forecast.

I don't think it's possible to compromise how Summer 2018 is going to pan out this year because there's such a divergence in the models, analogues and the current pattern. Therefore, I have no choice but to give two possible solutions for the Summer 2018.

The majority of the analogues have been pointing towards a poor Summer and for some, a very bad Summer indeed. It was looking very dire for the Summer outlook from multiple standpoints. The models at first weren't showing a particularly great Summer either. Basically, it was looking like there'd be a lot of northern blocking forcing the jet stream southwards to giving us depression after depression and very cool conditions. However, things started getting interesting first when we combined all the elements together to find the most common years within the analogues. These years were 1876, 1911, 1934, 1947, 1959, 1963, 1969, 1975, 1986, 1989, 1996, 2001, 2008 and 2013. What was intriguing about this particular analogue is that many of those Summers within it were great or good whether it was 1911's extended Summer from May to October, 1934's warm July, 1947's hot August, 1959's extended Summer from February to October with very sunny conditions, 1975's very warm and dry conditions throughout, 1989's very warm May and hot July or 2013's hot July. There were some very poor ones in there though like 1963 and 1986 which were both cool and wet. Nevertheless, most of them were good Summers which was more motivating to see for this Summer. From these analogues, June was looking like a very southeasterly month, July anticyclonic and August very thundery. That would make for quite an interesting Summer if it came off. The individual analogues showed a rather indifferent June with a chance of some warm, dry weather but a deterioration into July and August.

Whilst there still is some models that are going for an unsettled Summer and some cool but mostly warm, others have gone onto showing a very good Summer such as the CFSv2 (though underwhelming temperature anomalies) and the Beijing Climate Centre. They show a similar Summer to what my analogues show actually with June being settled and very southeasterly, July being anticyclonic and August very thundery; interesting how similar they are.

In terms of the current pattern, we have been in a constant wave of high pressure since February to the east drawing in these persistent easterly winds. Unlike in Winter, easterly winds can bring some very hot or warm conditions. Summer 1995 and 1983, two classics you tend to love, were very easterly sourced. Easterlies can also bring some quite torrential thunderstorms once a trough comes up from the Bay of Biscay, the Atlantic or France. Some severe thunderstorms have certainly been recorded in easterlies. Here we are at the end of May with continuous easterlies still going and with the weaker zonal flow, this is not likely to change. However, there is the infamous saying: "Return of the westerlies", that from the second half of June onwards the westerlies tend to come back and that's our Summer gone, a complete write off from that point on. However, this year seems to be different in every way from the unusually cold zonal westerlies in January to the beast from the east to Storm Emma to this late May warm spell etc. You'd have to go back to 2003 to find such a constant area of high pressure over Scandinavia I think which of course was a warm Summer and August in particular was hot. The problem with analogues this year is that I think they don't take this current unusual pattern into account thus why I'm not considering what the majority of them show regardless of the huge agreement among many of them.

The first solution is for a front loaded Summer. What this means is that we'll have our warm and dry weather in May and June but the weather will deteriorate through July and into August. But, there is a chance that the weather may improve in August at some point, not sure when, and a warm spell is likely to occur. If it does turn out to be a front loaded Summer, I don't think it'll be a huge disaster although after the May and June, it would feel pretty awful. July could be quite a cool month but maybe not very wet whilst August be fairly cool and very wet.

The second solution is for June to be settled and warm, July to be anticyclonic all around and potentially hot whilst August to be thundery but warm. This is the more popular or favoured solution at the moment in the way the models have gone as well as my analogues.

I'm not going to go all out and say scorcher Summer on the way but 2018 has the potential now with this Scandi High to be one of our better Summers of the 21st century so far. Now, it could go all down the tubes like Summer 2017 did (which is likely courtesy of the change from El Nino to La Nina very rapidly) so don't get too excited. This is only potential for now. As with all long range forecasting, it's not to be relied upon. Now go and enjoy the current weather, it's not too often we get prolonged fine periods like this.

tanko

How is the weather for next week looking?

sryanbruen

BBC monthly outlook.

- Continued similar conditions to the end of May into the start of June with thunderstorms and warm weather.
- Less settled and breezier mid-month period.
- Summer returns for the end afterwards

Seems to be in line with other forecasts. Reminds me of 1976 in some ways.

https://www.bbc.com/weather/outlook?ns_campaign=bbc_weather&ns_mchannel=social&ns_linkname=news_central&ns_source=twitter

sryanbruen

The NAO is expected to take a tumble into negative territory through the first week of June after being in a significant positive state since the middle of April. This index is less clear cut for Summer than it is for Winter. It can be very good or it can be brutal when it's negative.

For those who don't know, the NAO tells you the difference in mean sea level pressure between the Icelandic Low and the Azores High, two of the main key elements that make up Ireland's zonal pattern. When it's positive, both are in their normal state all strong giving us westerly winds. When it's negative, both elements are weak or non-existent and the Azores has the low whilst Iceland has the high.



I posted this reanalysis of Summer 1975 before but for this specific post, I thought it'd be good to bring up again. June 1975, a beautifully sunny, warm and dry month, had a negative NAO index which meant the Azores High was weak. The Summer 1975 reanalysis does show this very clearly, see the blue colours over the Azores or the Mediterranean noting the below average heights there. However, over Ireland is a big area of high pressure bringing fine conditions. If that high were to be out further west into the Atlantic, it would have been a pathetic Summer - see the below average heights to the northeast of Scandinavia so we were lucky!



NAO in Summer is complex. For the moment, it seems that regardless of this tumble the NAO is expected to go, we are to remain warm into the first week of June with thunderstorms and the chance of high pressure coming back to us from the north so the signs remain good!

sryanbruen

June 2007 started off with a similar spell of weather to what is expected to take place for June 2018 bar some very wet conditions on the 2nd/3rd that year. Let's hope Summer 2018 doesn't happen like Summer 2007! Fortunately, at this stage, 99.9% unlikely of that.



The only month with a CET of at least 18.0c this decade, the 2010s, has been July 2013 so you'd think they're due one. The 2000s had two such months, August 2003 and July 2006. The 1990s had five such months, August 1990, July 1994, July 1995, August 1995 and August 1997. The 1980s had two such months, July 1983 and July 1989. The 1970s had two such months, August 1975 and July 1976. The 1960s had no such months. We have seen the least amount of months with a CET of at least 18.0c since the 60s as a result.

Larbre34

Met Éireann giving "mid to high 20's" for next Weds and Thurs 6th and 7th. I've to pop over to London, no doubt it will be sultry and horrible

SNNUS

Let's hope the jet stream takes a long holiday this summer ..

Graces7

Quite horrible out there this morning. Thick low mist, no breeze and the midges are swarming.. Had to abandon walking the dog and seal the house.

West mayo; offshore island

SleetAndSnow

Ah summer. New season time to totally transition to a new thread.

Cloudy first day here in Cork City , warm and humid.

patneve2

Some hazy sunshine after a light rain shower. Humid and close. Wind not really in my favour today re. convection, hoping for a switch to SW winds in the afternoon but being exposed to the onshore wind isnt positive. Could be some impressive rainfall rates inland and will be an interesting day of weather watching inland.

pauldry

day 10 in a row of 19c or more in Sligo
yesterday....19.0c ...phew...today already 19c