Cold Spell - Feb 7th to 13th 2021 - Chat

Mount Vesuvius

The Dutch have named the system Darcy, they are expecting snow drifts.

Cheers GL, kinda hoping for some extra oomph in those showers.
Exactly when looking at surface isobars , angle the wind slightly to the left.

I remember back in November/December 2010 looking out over the Irish sea and watching those beautiful anvils up so high, if only again, pity.

lucernarian

Nqp15hhu wrote: »

It’s vertical shear and there’s not much going on.

For ex, in this Hodograph you can see the wind is mostly Easterly from the surface to 3000 metres.

That was a tired typo. Changed post now.

Larbre34

igCorcaigh wrote: »

Southeast England is looking at very bad disruption. Hope they are prepared.

Yeah, I expect to see deserted tube trains, quiet motorways, shops and pubs shut everywhere.....

lucernarian

The shear situation is not as optimal as 2010, which I guess I learned a lot from. But nothing disastrous, and as GL says there isn't 30 degree directional shear but at times and places it's >20. just might expect slightly "flabbier" streams. I also suspect there'll be a lot of groupel for parts but on that part I'm not experienced.

Nqp15hhu

lucernarian wrote: »

That was a tired typo. Changed post now.

Shear is required to aid thunderstorm development (to separate downdraft and updraft). So it doesn’t always break up precipitation.

igCorcaigh

Larbre34 wrote: »

Yeah, I expect to see deserted tube trains, quiet motorways, shops and pubs shut everywhere.....

Should be some snow too

Speak Now

smellyoldboot wrote: »

So I'm in Waterford and met eireann has the forecast for the foreseeable as "coldish" about 3 degrees and the odd bit of rain, which seems such a horrible damp squib. What gives? Is everyone else wrong and they know something or are they pure dopes?

Get your guidance from their text forecast, the automated location forecasts are crap just like every other app out there.

TTLF

I went to bed at about 10pm and woke up at 11:45pm because of a weather related nightmare relating to the wind directions and stuff via the ICON18Z

I think I need to seek professional help :pac:

Speak Now

TTLF wrote: »

I went to bed at about 10pm and woke up at 11:45pm because of a weather related nightmare relating to the wind directions and stuff via the ICON18Z

I think I need to seek professional help :pac:

Professionals like Met Eireann

Danno

Speak Now wrote: »

Get your guidance from their text forecast, the automated location forecasts are crap just like every other app out there.

And to add to that: the only certainty is that there is uncertainty.

Gaoth Laidir

The latest readings from the 00Z soundings. Upstream is more or less as you were at midday, though that dry layer at 850 hPa in the Ekofisk platform in the North Sea is gone now. A good snow sounding there.

The Netherlands and NW Germany are in for an absolute pasting tomorrow and Sunday.

Dazler97

Gaoth Laidir wrote: »

The latest readings from the 00Z soundings. Upstream is more or less as you were at midday, though that dry layer at 850 hPa in the Ekofisk platform in the North Sea is gone now. A good snow sounding there.

The Netherlands and NW Germany are in for an absolute pasting tomorrow and Sunday.

Wow - 13 in Shetland, ya know the cold air isn't far away now

Donegal Ken

MET ÉIREANN UPDATE
MONTHLY FORECAST, ISSUED FRIDAY 05 FEBRUARY 2021
Week 1 (Monday 08 February to Sunday 14 February)

Low pressure to the south of Ireland with high pressure to the north will establish a mainly easterly airflow over the country for this period. This easterly airflow will bring a colder airmass from Scandinavia over Ireland, leading to below average temperatures for the week. The fresh or strong easterly winds will also bring an added wind-chill factor. Precipitation amounts will vary. Showery conditions will feed into northeastern, eastern and southern areas leading to slightly above average precipitation amounts there. The west and northwest will be more sheltered in the easterly flow, leading to slightly below average precipitation amounts there.

With cold temperatures, wintry precipitation is likely. Showers over the eastern half of the country will fall as sleet and snow and there is potential for more widespread snowfall in the second half of the week. There will also be frost and ice at night, leading to hazardous conditions.

igCorcaigh

Very guarded language from ME, yet full of potential.

Donegal Ken

igCorcaigh wrote: »

Very guarded language from ME, yet full of potential.

They know as much as the rest of us. Will be Sunday before they start to give more details i think and possibly issue the first status yellow snow ice warnings for places. The will take it on a daily bases then and update warnings accordingly. I was talking to Evelyn Cusack this afternoon and she has said that the sea streamers will pose a great danger and the advisory was issued as still high degree of uncertaint but will be a interesting watch over this weekend.

Dazler97

Donegal Ken wrote: »

MET ÉIREANN UPDATE
MONTHLY FORECAST, ISSUED FRIDAY 05 FEBRUARY 2021
Week 1 (Monday 08 February to Sunday 14 February)

Low pressure to the south of Ireland with high pressure to the north will establish a mainly easterly airflow over the country for this period. This easterly airflow will bring a colder airmass from Scandinavia over Ireland, leading to below average temperatures for the week. The fresh or strong easterly winds will also bring an added wind-chill factor. Precipitation amounts will vary. Showery conditions will feed into northeastern, eastern and southern areas leading to slightly above average precipitation amounts there. The west and northwest will be more sheltered in the easterly flow, leading to slightly below average precipitation amounts there.

With cold temperatures, wintry precipitation is likely. Showers over the eastern half of the country will fall as sleet and snow and there is potential for more widespread snowfall in the second half of the week. There will also be frost and ice at night, leading to hazardous conditions.

Music to my ears

Mount Vesuvius

Donegal Ken wrote: »

They know as much as the rest of us. Will be Sunday before they start to give more details i think and possibly issue the first status yellow snow ice warnings for places. The will take it on a daily bases then and update warnings accordingly. I was talking to Evelyn Cusack this afternoon and she has said that the sea streamers will pose a great danger and the advisory was issued as still high degree of uncertaint but will be a interesting watch over this weekend.

Have her on speed dial eh.:D
Yeah come Sunday we should have a better idea but streamers are a now cast in my opinion as sometimes they can take on a life of their own, in favorable conditions obviously.

Expect feck all and hope to be pleasantly surprised.

TTLF

Those “streamers” of cold rain today Saturday already hitting me in S county Dublin and they’re very heavy too, can hear it bucketing down outside atm, was not expecting this nor expecting it this early into Saturday personally, really interesting times ahead. MÉ radar has this rain streamer ontop of me but other apps have it nowhere to be found on its radar...

Nqp15hhu

TTLF wrote: »

Those “streamers” of cold rain today Saturday already hitting me in S county Dublin and they’re very heavy too, can hear it bucketing down outside atm, was not expecting this nor expecting it this early into Saturday personally, really interesting times ahead. MÉ radar has this rain streamer ontop of me but other apps have it nowhere to be found on its radar...

That’s residual rain from the low over England.

Kermit.de.frog

Just want to say hi to the Met Eireann staff onlookers on night shift

Hi!

TTLF

Nqp15hhu wrote: »

That’s residual rain from the low over England.

Ah well that probably makes more sense, thought it was an easterly based off its direction into Dublin and the wild direction, although I’m p sure tomorrow there are rain showers constantly off the coast as that British low moves more SE...

Danno

Gaoth Laidir wrote: »

The Netherlands and NW Germany are in for an absolute pasting tomorrow and Sunday.

Good news,and once that snow is on the ground, the input obs into the models will change their output significantly.

The quicker these snowfields develop the better for us. If we can get large areas of E England in addition to NW Germany and Holland under snow the better for us downstream this week.

Mount Vesuvius

Yeah Go on DARCY, do your worst

https://www.metoffice.gov.uk/about-us/press-office/news/weather-and-climate/2021/storm-darcy-050221

Mount Vesuvius

Sea fetch for potential shallow convection in a more direct east to south east flow.
Should be enough fetch for some flurries at least on the coast of these.

Dublin to Liverpool- 219 Km

Dublin to Holyhead- 105 km

Rosslare to Fishguard- 99 Km

Mount Vesuvius

Might be useful to know this when the 925hpa winds (about 780 Metres) are flowing up to the similar direction of 850hpa flow.
So if we do get low cloud that is enough for flurries

Mount Vesuvius

Actually 850hpa flow looks way too fast when direction turns easterly.
Need it under 50 kph, not enough time for warm parcels of air to rise and create between the narrow sea fetch.

Mount Vesuvius

Met Éireann NATIONAL OUTLOOK
SUMMARY: Wintry showers, mainly in eastern counties, largely dry elsewhere. Feeling very cold during the days with low temperatures and windchill. Frosty and icy nights.

Sunday night: Isolated wintry showers will affect eastern and northern areas with a dusting of snow possible. Lowest temperatures of -2 to +1 degrees, coldest over Ulster, with widespread frost and ice, in moderating easterly breezes.

Monday: Scattered wintry showers will continue to move in from the Irish Sea to eastern and northern coasts with some bright and sunny spells developing there, mainly dry elsewhere. Daytime temperatures will only reach highs of 1 to 3 degrees in moderate to fresh easterly winds.

Monday night: Wintry showers will become more frequent and push further inland later in the night. Very cold with clear spells and lowest temperatures of -3 to 0 degrees with a widespread sharp frost under clearing skies. Mist and fog will develop too in mainly moderate easterly winds, fresh to strong in the southwest.

Tuesday: Staying very cold with again, daytime highs of just 1 to 3 degrees in fresh easterly winds, strong on southern coasts. Wintry showers will continue to feed in from the east, affecting mainly the northeast and east with some accumulations possible. More isolated showers will continue to reach further inland. Turning bitterly cold overnight with lowest temperatures of -4 to 0 degrees with a severe frost and icy stretches causing hazardous conditions. Winds will ease overnight with fog developing.

Wednesday: Further wintry showers will occur through Wednesday. Highest temperatures only reaching 2 or 3 degrees for much of the country. Light to moderate easterly winds will freshen on Atlantic coasts towards the evening as a band of rain arrives from the southwest, gradually extending into much of Munster overnight, preceded by falls of sleet and snow. Another very cold night with lowest temperatures of -4 to -0 degrees.

Further outlook: Very windy on Thursday with further falls of sleet and snow over much of the country, with more persistent rain developing in the southwest. Temperatures will increase towards the weekend.

Humberto Salazar

Away from the exposed east northeast areas, there's little snow wise of interest for those of us away from there over the next 4 days. Thursday is the interesting day, frontal snow can be disruptive. Plenty of frost, ice, crisp days ahead with biting wind, great for walks. Wrap up.

Mount Vesuvius

Humberto Salazar wrote: »

Away from the exposed east northeast areas, there's little snow wise of interest for those of us away from there over the next 4 days. Thursday is the interesting day, frontal snow can be disruptive. Plenty of frost, ice, crisp days ahead with biting wind, great for walks. Wrap up.

Showers will go far inland on Tuesday north of Dublin to Louth, perhaps all the way across to Mayo

Oneiric 3

Donegal Ken wrote: »

I was talking to Evelyn Cusack this afternoon and she has said that the sea streamers will pose a great danger .

For God's sake, do not let the press get their hands on that statement.

"Met Eireann Expert Warns that Sea Streamers Pose 'Great Danger' to Public".