Winter 20/21 - General Discussion

Larbre34

Lets face it, in those 50/50 scenarios for air origin dominance that occur most years, we are on the wrong side of the eventual boundary 80% of the time.

Its clear now that for the foreseeable forecast period, we shall be too.

Higher pressure to our east will de-power the Atlantic in our vicinity to an extent, so we're unlikely to see any severe winter wind storms either. Most likely, following this weekend, through to the end of the month, it'll be 6 to 9 degree daytimes, with drizzle and an occasional night frost when the sky clears.

John O.Groats

Arduach wrote: »

Let's wish them a poor start with their new venture (with that forecast)

If as seems likely that mid breezy wet weather becomes re established in the next week or so it will most likely stay that way for the rest of the winter. Maybe early March will see some colder weather return but at that stage it will be too late for any long lasting snowfall.

Billcarson

John O.Groats wrote: »

If as seems likely that mid breezy wet weather becomes re established in the next week or so it will most likely stay that way for the rest of the winter. Maybe early March will see some colder weather return but at that stage it will be too late for any long lasting snowfall.

Would be silly to write off feb at this stage though.

nacho libre

I for one will miss these cold and dry days. There is nothing appealing to me in standard Atlantic weather or a high with weak fronts over the top of it bringing days of drizzle.

John O.Groats

Billcarson wrote: »

Would be silly to write off feb at this stage though.

Over the last 40 odd years I can only remember Feb 1986, Feb 1991 and of course the last few days of Feb 2018 as having exceptionally cold and/or snowy weather conditions. The last 2 years in particular had above average temperatures during that month. I would bet that Feb this year will be the same story again.

Nqp15hhu

Hmmm not sure where all the negativity is coming from. As I said previously, our snow came in February last year.

This airmass is cold but it has too steep lapse rates and the winds are just bringing in cloud, rather than showers.

So what do we need?

Air Pressure: 1000mb or less, for showers.
Lapse rates: <3c per thousand feet because a steep lapse rate increases the depth of the above freezing layer.
Freezing level: <400 metres.
850hPa temperature: <-6c at 5,000 feet


The high air pressure limits shower development.

Humberto Salazar

Zogabomb wrote: »

Met Eireann's first monthly forecast doesn't look good for cold fans over the next 4 weeks, probably based on ECM Monthly.

Week 1 (Friday 08 January to Thursday 14 January)

High pressure is expected to influence Ireland’s weather during this week. A north or northeast air-flow looks set to dominate early in the period before the air-flow becomes variable as high pressure builds in over the country. Mean air temperatures are expected to be below average with a risk of frost, ice and some wintry precipitation. However, it looks set to turn a little less cold later in the period. Soil temperatures are expected to run below the seasonal-norm. As high pressure will be the dominant feature of the weather, is expected to be drier than normal for early to mid-January with only small amounts of rainfall forecast.

Week 2 (Friday 15 January to Thursday 21 January)

Forecast confidence declines in week 2 but there is an indication that weather conditions will turn more unsettled. High pressure is forecast to decline with some frontal systems moving through. Mean air temperatures are expected to be near-average for January with a reduced risk of frost and ice as compared to previous weeks. Rainfall totals are expected to be higher than in previous weeks with rainfall amounts forecast to be around average for mid-Winter, possibly higher than average in parts of the south.

Week 3 (Friday 22 January to Thursday 28 January)

By late January, there is lower confidence in the forecast but there is a signal for weather conditions to remain fairly unsettled with low pressure situated close to Ireland. Mean air temperatures are expected to be above average with a reduced risk of frost and ice as compared to the climatological average. As low pressure will quite dominant with frontal troughs nearby, it looks set to be wetter than average across most of the country. Forecast confidence falls lower by the end of the period but it looks set to stay rather unsettled.

Week 4 (Friday 29 January to Thursday 04 February)

By forecast week 4 confidence is much lower. However, there is a trend towards unsettled weather with low pressure expected to be positioned nearby Ireland. Mean air temperatures are forecast to be slightly above average for the time of year across much of the country whilst rainfall totals are projected to be above average.

Confidence is low that many here will appreciate this forecast, but it should be useful to see how accurate they are in future.

Rock Lesnar

0.2c here in meath, was out for a walk there and the roads are very slippy, plenty of ice stretches still around

circadian

Another hail shower here in D9.

Rebelbrowser

Cracking weather at the mo imho. Its been frosty by night and blue sky by day down here for the last 4 days. Much preferable to usual wind and rain.... No sign of any rain for the next few days either. Great.

d51984

Heavy brief shower of Hail, lasted about 5 mins max.

Dublin 17

mcburns07

Rebelbrowser wrote: »

Cracking weather at the mo imho. Its been frosty by night and blue sky by day down here for the last 4 days. Much preferable to usual wind and rain.... No sign of any rain for the next few days either. Great.

Fantastic, the ground is actually starting to dry out, in Jan :eek:

Billcarson

John O.Groats wrote: »

Over the last 40 odd years I can only remember Feb 1986, Feb 1991 and of course the last few days of Feb 2018 as having exceptionally cold and/or snowy weather conditions. The last 2 years in particular had above average temperatures during that month. I would bet that Feb this year will be the same story again.

You could very well end up being right but I think over the last 40 odd yrs Feb has been a better chance for cold spells then jan,not that that is saying much .

Cold spells also in Feb you didn't mention although not as good as the ones you did mention . Late feb/ into early march 2001,late feb 2005, late feb / early march 2006 and early feb 2009. Of which 2001 and 2009 were the best of those.

nacho libre

I agree. While the most notable cold spells tended to be in December, over the years February was the month I most often had snow in

Gonzo

nacho libre wrote: »

I agree. While the most notable cold spells tended to be in December, over the years February was the month I most often had snow in

for me most snow events over the past 20 years are either in February or March and March probably more than February. December 2010 is basically on it's own and the last time I remember a proper snowy January was probably way back in the early 1990s.

daniel_t1409

It snowed here in wexford in February 2013 and early February 2018 as well at the end of Feb 2018. March 2013 and 2018 brought snow too, the latter was not associated with the BFTE event.

Billcarson

Gonzo wrote: »

for me most snow events over the past 20 years are either in February or March and March probably more than February. December 2010 is basically on it's own and the last time I remember a proper snowy January was probably way back in the early 1990s.

What about first half half of jan 2010? That was our last proper January cold spell.

Gaoth Laidir

Airport warnings, valid overnight:

Severe ground frost and moderate air frost forecast for Knock airport. Also moderate air frost at Shannon.

(Knock) EIKN AD WRNG 01 VALID 051700/061200 FROST SEV GND AND MOD AIR FCST=
(Shannon) EINN AD WRNG 01 VALID 051700/061100 FROST MOD GND AND MOD AIR FCST=
(Casement) EIME AD WRNG 01 VALID 052300/061100 FROST FBL GND AND FBL AIR FCST=
(Cork) EICK AD WRNG 01 VALID 051700/061100 FROST FBL GND AND FBL AIR FCST=
(Dublin) EIDW AD WRNG 01 VALID 060100/061100 FROST FBL GND FCST=

Belfast Aldergrove (UKMO)

Frost
Issued at: Tue 05 Jan 2021 - 12:31 UTC
Valid from: Tue 05 Jan 2021 - 18:00 UTC
Valid to: Wed 06 Jan 2021 - 11:00 UTC
A GROUND FROST IS LIKELY TO OCCUR. FROZEN DEPOSITS MAY FORM ON PARKED AIRCRAFT, RUNWAYS AND TAXIWAYS.

Frost
Issued at: Tue 05 Jan 2021 - 12:31 UTC
Valid from: Tue 05 Jan 2021 - 20:00 UTC
Valid to: Wed 06 Jan 2021 - 09:00 UTC
AN AIR FROST MAY OCCUR. FROZEN DEPOSITS MAY FORM ON PARKED AIRCRAFT.

Freezing Precipitation
Issued at: Tue 05 Jan 2021 - 16:09 UTC
Valid from: Tue 05 Jan 2021 - 20:00 UTC
Valid to: Wed 06 Jan 2021 - 09:00 UTC
ISOLATED LIGHT RAIN SHOWERS MAY FREEZE ON CONTACT WITH PARKED AIRCRAFT, RUNWAYS AND TAXIWAYS. CLEAR ICE MAY FORM CAUSING HAZARDOUS CONDITIONS.

Snow
Issued at: Tue 05 Jan 2021 - 16:09 UTC
Valid from: Tue 05 Jan 2021 - 19:00 UTC
Valid to: Wed 06 Jan 2021 - 10:00 UTC
SLIGHT RAIN AND SNOW SHOWERS MAY OCCUR AT THE AIRFIELD BUT NO SIGNIFICANT ACCUMULATIONS ARE EXPECTED.

Derry Eglinton

Frost
Issued at: Tue 05 Jan 2021 - 11:32 UTC
Valid from: Tue 05 Jan 2021 - 18:00 UTC
Valid to: Wed 06 Jan 2021 - 00:00 UTC
GROUND AND AIR FROST IS LIKELY TO OCCUR. FROZEN DEPOSITS MAY FORM ON PARKED AIRCRAFT, RUNWAYS AND TAXIWAYS.

Oscar Bravo

https://twitter.com/MetEireann/status/1346493135971610624?s=19

circadian

Huge black cloud heading southwest from Dublin, someone somewhere is bound to get some snow.

Edit: moving slowly, could be coming towards me. Having a dougal moment.

Nqp15hhu

A lot of cloud forming over Scotland which may spoil my chance of a hard frost once again.

pad199207

circadian wrote: »

Huge black cloud heading southwest from Dublin, someone somewhere is bound to get some snow.

Edit: moving slowly, could be coming towards me. Having a dougal moment.

Moderate hail from it here in KE

Hooter23

Looks like thursday morning is the big event during this cold spell...not much but met eireann are confident of a "light dusting for most places" there is milder air coming with it but it arrives at the coldest time of the morning which might be enough to offset the milder air and for it to fall as snow...everything is in place at the right time..now just watch as it all goes wrong again...we will never learn

Arduach

A fairly big January snow anniversary coming up for most of the interior of the country. In 3 days time it'll be 30 years since the big snowfall of Tuesday 8th January 1991. I think returning polar maritime air.

A week off boarding school. Nice only from my homeplace it took 2 days to be rescued by tractor!

Oscar Bravo

Casement reporting a light shower of rain and hail at 1630. Temperature 3.dewpoint 1


EIME 051630Z 04009KT 9999 -SHRAGS FEW018CB BKN023 BKN050 03/01 Q1027

bosco12345

Looks like slightly milder weather is on the way by Sunday which will end this very mediocre 2 week spell cold spell. I see Met Eireanne now have a monthly forecast and going with milder weather right through to the end of January. Lets hope the SSW delivers us some significant cold in Feb, but its a toss of a coin I believe. In the meantime, going to enjoy this cold week ahead, with an ice day on the cards for the north midlands tomorrow with potentially a few cm's of snow Thursday morning.

Oscar Bravo

Hooter23 wrote: »

Looks like thursday morning is the big event during this cold spell...not much but met eireann are confident of a "light dusting for most places" there is milder air coming with it but it arrives at the coldest time of the morning which might be enough to offset the milder air and for it to fall as snow...everything is in place at the right time..now just watch as it all goes wrong again...we will never learn

Some details on this link
https://twitter.com/MetEireann/status/1346388427353296896?s=19

Arduach

Oscar Bravo wrote: »

Some details on this link
https://twitter.com/MetEireann/status/1346388427353296896?s=19

6 or 7 killed iirc.

3 days later it dragged down that returning polar maritime air in it's wake for snowfall.

sryanbruen

Arduach wrote: »

A fairly big January snow anniversary coming up for most of the interior of the country. In 3 days time it'll be 30 years since the big snowfall of Tuesday 8th January 1991. I think returning polar maritime air.

A week off boarding school. Nice only from my homeplace it took 2 days to be rescued by tractor!

Yes, a wintry few days that was following the major windstorm on this day back then. It wasn't severely cold like the easterly that would follow in early February that winter but it was cold enough to produce a significant snow event that you mention.

Casement had 15cm depth on the evening of the 8th and Birr had 9cm depth. Quite an unusual period.

Billcarson

Living in Dublin at the time, the snowfall of 8th jan was a rain to snow event where I lived. Got a few inches of snow from it during the afternoon/ evening.