Recent notable weather extremes (temp, sunshine, rainfall) in Ireland

Mothman

I propose making this a sticky. Mods, change title etc as you see fit.
The plan is to note notable daily, monthly extremes of certain elements in this thread.These would mostly relate to the synoptic stations. I'll include sources later

For example

22nd November 2005

• Casement –5.3ºC lowest Nov temp at station since 1988 and lowest Nov temp in Ireland(at synoptic stations) since 1996

• Dublin Airport –3.4ºC Equal lowest Nov temp at station since at least 1958, equalling temp set in 1972

• Belmullet –0.3ºC lowest Nov temp at station since 1990

Danno

Excellent idea Mothman, will you keep it updated daily? - I hope so!

Mothman

Danno wrote:

Excellent idea Mothman, will you keep it updated daily? - I hope so!

Certainly won't be daily, but what I (or others if they want to contribute)consider notable.

Mothman

October 2005

Rainfall

• 220mm (175% of normal) at Cork Airport, Wettest October since 1996, Wettest month since Jan 2001 at the station

Sunshine

• 65hrs(74%) Cork Airport, Dullest October since 1990

• 87hrs Dublin Airport Dullest October since 1996

• 89hrs (88%) Rosslare Dullest October since 1996

Temperatures above normal at all stations, but nowhere was it as warm as Oct 2001

Mothman

Sunshine 22nd Nov 2005

6.9h at Malin Head, sunniest Nov day at station since 1984

Wind 21st Nov

Mean speed at Casement of 0.1kt (0.1mph)
It's extemely rare to have a mean so low for a whole day. Although Belmullet did have a 0.0kt mean on a day in recent months.

Note that Casement had a mean of only 0.6kt (0.7mph) on the following day 22nd Nov, the morning that -5.3C was recorded

Mothman

I was going to put these into first message, but I can't edit it.

• Central Statistics Office. They have monthly records going back to 1958 of most of the synoptic stations. Sadly this does not include Knock, and also Roches Point and Claremorris since they went automatic.

• Met Eireann Recent Weather. Most of us will know this one and also the daily weather station reports are available for past 6 months. When this first came out, one could get the reports for a range of dates, but now it is only for one day, so not near as useful

• Monthly Weather Bulletin Listed near bottom of link. I receive this and it gives details for about 30 stations. There is a time delay of 3 months or so. I've just received August. The subscription rate is steep enough. However, the same link mentions a Monthly Weather Summary, which is free by e-mail. It's a pdf file and is usually sent on the first working morning after the month has finished. Definitely worth getting

• I'm also a member of COL (Climatoligical Observers Link) The monthly bulletin is published on about the 20th of the month after and woukd have some info relating to Irish stations.

Mothman

Wind 25th November
I'm quite sure that Malin Head had a mean wind speed for the whole day of at least 40mph. Met Eireann didn't update thier recent weather page, so haven't got the figure at hand yet but it should be available during next couple days.
But here are the hourly obs with force and max gust (mph)

Force 7 is mean 32-38mph.
gale 8 is mean 39-46mph
strong gale 9 mean 47-54mph
Storm force 10 is mean 55-63mph

0100 8 56
02 7 65
03 7 60
04 7 56
05 8 58
06 8 63
07 8 60
08 9 67
09 10 74
10 9 76
11 9 70
12 9 81
13 9 74
14 9 74
15 9 74
16 no data
17 9 70
18 9 76
19 9 74
20 8 71
21 7 67
22 7
23 8 67
24 8 63

To put a perspective on it, the highest mean (10 minute) I've recorded during past 6 years or so, is 43mph. I estimate that the mean at Malin Head for the whole day to be 43-44mph. The highest mean for a whole day that I've recorded is just 26mph and the highest this month just 20.5mph, also on the 25th, with max mean of 29mph and gust of 50mph.

This probably does happen at Malin Head on a few occassions every year, but I'm sure in anyones language, it makes it a very windy day.

Mothman

Mothman wrote:

Wind 25th November
I'm quite sure that Malin Head had a mean wind speed for the whole day of at least 40mph.

The data for 25th only became available today, and Malin Head had a mean speed for the whole day in excess of 45mph (39.5 knots) :eek: :eek:

Wow

I know their anemometer is probably at a decent height and exposure compared to mine...

But that average is more or equal to my maximum gust

Mothman

Earthman wrote:

Wow

I know their anemometer is probably at a decent height and exposure compared to mine...

The standard recording height is 10m, however the anemometer height at Malin Head is 18m. Why this is I've no idea. Would probably add couple mph to the mean speed for the day.

Mothman

At all stations, sunnier than Nov 2004, but at most stations not as sunny as Nov 2003.
Nov 05 was sunnier than Oct 05 at nearly every station.

Belmullet 75hrs, sunniest Nov since 1985
Valentia 74hrs, sunniest Nov since 1985
Dublin Airport 98 hrs, Sunniest Nov since records began in 1941.
Malin Head 70hrs sunniest Nov since 1959
Shannon 81hrs sunniest Nov since at least 1990

Temperature wise, coldest since 2000 at all stations except Casement, where it was coldest Nov 1996

Mothman

Valentia 52.0mm This is a 00-24h total.

The database I have is for the standard met day which is 09-09h, so can't make direct comparisons, but IF 52.0mm fell during a met day, it would equal a daily fall recorded in Dec 1983, which was highest in Dec since 1959.

I do know that 52.0mm is the highest 00-24h daily fall at Valentia since 9th June 2003

Mothman

Max of 0.9C at Knock Airport

Must say, that I'm clutching at straws a bit as 0.9C max is not really that notable, and is argueably not nearly an "ice day", but this month has been so uneventful, I'm grabbing onto anything.

For those whose don't know, An "ice day" is when the max temp stays below 0.0C.

There is not readily available data concerning low maxes, but from the info I have since beginning of 2000, there has been one period when ice days were widespread. This was during last week December 2000. I've very little actual data, but reading a couple graphs, Dublin and Mullingar recorded ice days from Dec 28th-30th and Shannon on Dec 30th.

Also somewhere recorded an ice day on the 27th. On both the 28th and 30th maxes of -3C was recorded.

The only other occassion I can find of an ice day at the synoptic stations (since 2000) is Jan 5th 2003. I can confirm that Clones had an ice day then and possibly other midland stations. There are many occassions with max of 1C so making the 0.9C at Knock not really notable.

The most likely events that result in ice days is when snow is on the ground or when fog does not lift for the day.

Most of the country was covered in snow during late Dec 2000 following a polar low that formed off NW coast on the 27th. The following day a low drifted down the east coast giving further accumulations. High pressure formed and the ice days continued to the 30th

Scubadevils

Mothman wrote:

Most of the country was covered in snow during late Dec 2000 following a polar low that formed off NW coast on the 27th. The following day a low drifted down the east coast giving further accumulations. High pressure formed and the ice days continued to the 30th

I don't remember that, was Dublin included?

Mothman

Felixdhc wrote:

I don't remember that, was Dublin included?

I don't either, but this quote from Met eireann Dec 2000 monthly bulletin
28th Dec 2000

The north, west and midlands fared worst but later in the day the snow showers extended to the east and all areas had accumulations with the southwest and southeast being the only exceptions

Of course substitute worst with best

Casement recorded 10mm that day, I recorded less than a mm.

Scubadevils

Mothman wrote:

I don't either, but this quote from Met eireann Dec 2000 monthly bulletin
28th Dec 2000



Of course substitute worst with best

Casement recorded 10mm that day, I recorded less than a mm.

Interesting, I wasn't doubting you either - just don't remember it which is unusual for me

Mothman

Here's something notable that I overlooked.
I don't have specific pressure data, but on the 12th December, pressure reached approx 1046.5mb in the NW.

On Philip Edens site,

High sea-level pressure: reached 1046.9mbar at Castlederg (Tyrone) at 11z, possibly the highest
since Jan 1992, and the highest in December since 1980

The above quote refers to UK, but may well apply to here as well.

I don't know when the lowest pressure of year was, possible one of the early Nov storms that produced the very strong wind at Belmullet, but with me the lowest pressure of year was on 2nd Dec at just above 970mb, 10 days later the pressure almost got to 1045mb. A rise of almost 75mb.

If I come across any concrete data, I'll update.

Supercell

Didnt see this link before and only just noticed it myself on the Met Eireann site.

Some pretty nice 30 year averages for various Irish sites on http://www.met.ie/climate/30yearaverages.asp

The reference period is 1961-90 unfortunately instead of 1971-00 which would be more representative of the current milder climate (this is the standard reference period used by the British Met Office too, so is a valid period to use for comparitive purposes) , but nonetheless pretty interesting reading.

Its got means, extremes and breaks down frequencies of the various types of conditions, all in all pretty nice.

Mothman

Warmest year on record at Casement and warmest since 97 or 98 at many other stations.

Min temp of -5.6C at Casement on 3rd March is highest min in a calender year since -5.5C in 1998 and before that -5.4C in 1990 at the synoptic stations.

Casement recorded sub -5C on at least 3 days, I don't think any other synoptic station recorded -5C or below.

Mothman

Mean windspeeds lowest on record for December at both Rosslare and Cork Airport

Mothman

Mothman wrote:

Casement recorded sub -5C on at least 3 days, I don't think any other stations recorded -5C or below.

I saw a -5.8c at one of the NRA stations on the N2 on the wenesday night before new years eve.
Doesnt count I suppose, but its important to note it happened.
There surely must be stations like yours near that location whose stats for that night havent been tabulated yet?

There was also a -5c at the Baltinglass station a few months ago, in either late sept or october(must have been October iirc)

Mothman

Earthman wrote:

There surely must be stations like yours near that location whose stats for that night havent been tabulated yet?

I'll edit post and put in synoptic stations

Mothman

Hard to believe that this is the 2nd highest January max at Cork Airport since the station opened in 1961. However a long way behind the 16.1C recorded on 26th Jan 2003.

The station is 162m above sea level and that is probably main reason why 13C is not usually reached in January. Today was only the 2nd time!

Danno

Wasn't Midleton at 17.2c on Jan 26th 2003? If I remember Evelyn Cusack on the 6.25z broadcast that Sunday?

Mothman

While the sunshine stats won't be available till tomorrow, I'm expecting some exceptional figures for today at least the sunniest Jan day for 20 or so years at a station or 2 or even on record.
I recorded 7.8h which is higher the max recorded at some stations.

Here are the highest figures at each station since 1958 along with the year. A confirmed station record is in bold.
Edit, 29th Jan 2006 sunshine in red
Belmullet 8.0 1959 8.3 probable station record
Birr 7.4 1998 7.6 Highest since at least 1957
Valentia 7.5 1971,91,93 7.4 Highest since 1993
Casement 8.1 1987 7.9 Highest since 1987
Clones 7.8 1959 0.0 fog all day
Cork AP 8.1 2005 8.5 station record
Dublin AP 8.0 1987 7.7 Highest since 1987
Kilkenny 8.2 1977 8.4 Highest since at least 1957
Malin Head 7.5 1965 7.5 Highest since 1965
Mullingar 8.1 1977 8.2 Highest since at least 1957
Rosslare 8.2 1979 7.6 Highest since 2004
Shannon 8.1 1997 6.5

Also 8.1h at Knock,but I've no historical data, but I think a station record is very likely.

Mothman

Some exceptional low humidity and Dewpoint figures at Valentia 29/1/2006
It was similar to March 19th last year when 21C was recorded at Valentia, in that the wind is from east and as it the decends from the mountains to east of Valentia, it dries and increases in temperature


Here are hourly data. Formatting doesn't hold, but you should be able to decipher
29th Jan 2006 Valentia
Temp Hum Dp
00z 4 65 -2.3
01z 3 69 -2.6
02z 4 49 -5.5
03z 9 24 -10.9
04z 8 25 -10.6
05z 9 26 -10.1
06z 9 28 -9
07z 8 25 -10.7
08z 9 23 -11.4
09z 6 48 -5.9
10z 8 36 -6.7
11z 10 38 -3.7
12z 10 38 -3.2
13z 11 38 -2.3
14z 12 34 -3.2
15z 12 36 -2.4
16z 11 43 -1.4
17z 9 54 0.1

Mothman

A lot going on today, as well as the sunshine and the happenings at Valentia, it's worth mentioning, that
The max at Clones was +0.9C
The max at Valentia 12.9c
The min at Birr, -5.4C with grass min of -12C, the max at Birr was 10.0C giving a temp range of 15.4C

While I was driving to cork this morning I heard dec meehan on Today fm reading texts of people reporting their car thermometers in cavan and monaghan showing -6 :eek:

Danno

Something unusual there bud!

Mothman

I've put in Jan 29th sunshine data, by editing the above post. I'll put in the other figures when available

Mothman

Birr had a max temp of -0.4C, Clones not far behind, though the other side of zero with +0.3C, so not an ice day.
See this earlier post for more on ice day
Note that Clones had max of 0.3C yesterday (29th) Fog is reason for the temps not rising to levels experienced around the rest of country.

Also this morning, saw the lowest temps in Ireland since Mar 04, with -6C at both Kilkenny and Birr and grass min of -14C at Birr. Don't have figures to the tenth at hand.