This week's Indian Summer

Su Campu

The generally accepted definition of an Indian Summer is a period of mild weather (temperatures at least 21°C) occuring in late Autumn, after the leaves have turned, and before the first snows (and some say it has to occur after the first frost). It looks like we'll be having one in the next few days, as the warm continental airmass (850hPa temperatures as high as 15°C tomorrow) is advected in east to southeasterly winds. Western areas could reach the 21°C benchmark over the weekend, with eastern and southern areas in the mid-high teens.

Oscar Bravo

19 Degrees on the 2300 Reports at Valentia....not bad for the 8th of October!!

Deep Easterly

Just rooting through the stats for some of the met eireann stations for October and without a doubt, 1959 saw the highest October temperatures to date. (based on records since 1945).

The opening days of October 1959 saw a synoptic set up pretty similar to the current one, with a long fetch southerly airflow being pumped up from the Iberian Peninsula between a blocking high over eastern Europe and low pressure in the mid-Atlantic.

Highest temperatures were recorded on the 4th October of that year.

Chart for 12utc 4th October 1959:



Look familiar??? :pac:

Highest temperatures recorded on that day from a select number of Met Eireann Stations:

Kilkenny: 23.7c
Valentia: 23.5c
Birr: 23.2c
Shannon Apt: 23.0c
Mullingar: 22.9c
Shannon: 23.0c
Claremorris: 21.7c
Malin Head: 21.1c
Belmullet: 21.7c
Dublin Apt: 20.7c
Rosslare: 20.3c

Will October 2010's max's compare? we'll see..

duckysauce

what was the winter like after that spell?

Deep Easterly

duckysauce wrote: »

what was the winter like after that spell?

Average December; average to cool January followed by a cold February.

Shannon Apt/Dublin Apt combined deviation values from the unified 61-90 average of both these stations:

December 1959: +0.1c
January 1960: -0.3c
February 1960: -1.6c

Overall 1959/1960 winter deviation value: -0.5c

Birdnuts

Isn't there a theory out there that says the odds of a harsh winter are increased following a warm dry October?? - if thats the case, going on tonights runs were in for a good un:D

Min

Oakpark in Carlow was warmest yesterday for a met Eireann station - 20.6C.
Probably warmer in Kilkenny since it is surrounded by hills.

20.5C for Valentia
20.4C for Gurteen


Just the three stations over 20C yesterday.

up for anything

I don't know what the temp was here in Kilkenny yesterday, but it turned out to be an amazing day. Very sunny with a warm breeze. Started off a bit grey and miserable in the morning though, a bit like today. I hope the cloud burns off this morning.

ch750536

Indian summer?

30kph winds included in that?

jambofc

wish the indians would move over here a bit it's 14c with a strong breeze and it's cold i tell you......

Deep Easterly

Wind freqently gusting between 35mph & 40mph here now. Wasn't expecting it to be this windy myself today. Temp struggling to get beyond 16c as a result but still feels very warm under a sultry looking hazy sky!

Gonzo

no indian summer here today, cool, windy, slate grey skies, looks like it could rain any second.

bryaner

jambofc wrote: »

wish the indians would move over here a bit it's 14c with a strong breeze and it's cold i tell you......

+1 on that

Deep Easterly

Mean windspeed is increasing big time here, up to 24mph now :eek:. Gusts speeds are not increasing though and are hovering around 35mph at best. The wailing noise of the wind through the wires outside is incredible!

Su Campu

The problem is rich moisture trapped in the boundary layer beneath the strong inversion at around 920hPa (in the Nottingham sounding below, which shows conditions in the airmass upstream from us). But tomorrow and Monday drier conditions should move in and give a better chance of sunny and calmer conditions as the High centre moves south over us.





Incidentally, there are amazing standing waves visible over Ulster in the satellite loop, as this moist boundary layer is forced up over the terrain and into the inversion, where it becomes negatively buoyant and continues downstream in a wave-like motion, forming many stationary Sc lenticularis.

Deep Easterly

Just looking at the Davis v2 data I have, the sudden increase in wind over the last hour or so corresponded with very small but very sharp drop in air pressure. Went from a steady 1012.3mb down to 1011.5mb as the wind increased. Mean windspeed now is back down to 17mph with air pressure now minutely rising again, now up to 1011.7mb!!!!!!

Edit: Pressure still rising but another surge of noisy wind moving through with mean windspeed on the increase again!

Danno

October 8th...

Kilkenny City - Screen Max: 21.3c
Durrow, Laois County - Screen Max: 20.8c

GSF

Indian summer my ***. Today in Dublin was more like spending a day in Grimsby in winter with an easterly gale blowing.

Su Campu

Didn't reach 20°C today.

Max temperatures to 7pm

1 Shannon Airport (Ireland) 19.6 °C
2 Valentia Observatory (Ireland) 19.4 °C
3 Belmullet (Ireland) 18.3 °C
4 Gurteen (Ireland) 18.1 °C
5 Mace Head (Ireland) 17.9 °C
6 Oak Park, Carlow (Ireland) 17.6 °C
7 Casement Aerodrome (Ireland) 17.5 °C
8 Claremorris (Ireland) 17.5 °C
9 Finner (Ireland) 16.5 °C
10 Mullingar (Ireland) 16.5 °C
11 Johnstown Castle (Ireland) 16.3 °C
12 Malin Head (Ireland) 16.3 °C
13 Sherkin Island (Ireland) 15.8 °C
14 Roches Point (Ireland) 15.6 °C
15 Connaught Airport (Ireland) 15.4 °C
16 Dublin Airport (Ireland) 15.4 °C
17 Cork Airport (Ireland) 14.8 °C

Minima

1 Connaught Airport (Ireland) 12.8 °C
2 Dublin Airport (Ireland) 13.2 °C
3 Mullingar (Ireland) 13.2 °C
4 Casement Aerodrome (Ireland) 13.3 °C
5 Malin Head (Ireland) 13.5 °C
6 Finner (Ireland) 14.0 °C
7 Cork Airport (Ireland) 14.2 °C
8 Gurteen (Ireland) 14.5 °C
9 Mace Head (Ireland) 14.5 °C
10 Johnstown Castle (Ireland) 14.7 °C
11 Belmullet (Ireland) 14.8 °C
12 Claremorris (Ireland) 15.0 °C
13 Oak Park, Carlow (Ireland) 15.0 °C
14 Roches Point (Ireland) 15.0 °C
15 Sherkin Island (Ireland) 15.1 °C
16 Shannon Airport (Ireland) 16.1 °C
17 Valentia Observatory (Ireland) 17.1 °C

Su Campu

It's amazing to see the freezing level at over 3,400m (11,100ft), and getting to 3,800m (12,500ft) Tuesday! :eek: By next Sunday, the GFS has it back down to 1400m in the north, while 3000m in the south - that should give rise to some pretty decent rainfall!






Here are today's 18Z Valentia sounding data

Su Campu

The sun has just made an appearance here now and it's turned a typical "anticyclonic gloomy" day into a marvellous "Goldener Oktober" evening. This clearance should move westwards this evening, and tomorrow we should get some decent spells of sunshine after early fog clears.

We almost got away with no cloud, it's just that the boundary layer moisture was deep enough yesterday and today for the dewpoint and temperature curves to meet just before the inversion, which led to the layer of low cloud.

Deep Easterly

Nice autumnal day today I thought. Very little variation in temperature though since midnight with temp only peaking at 13.4c during the afternoon, about 1.0c higher than during the night!


Davis v2 readings

falling a little more sharply over the last couple of hours.