Cold Spell Late Feb/ Early March Technical Discussion only MOD NOTE POST #1

RustyGate

tanko wrote: »

Was storm Emma forecast to be so slow moving, it hardly seems to be moving at all. Is it not supposed to head off out into the Atlantic?

It was forecast to be slow moving/stalling by the graphics the BBC had on the weather forecast on their website way back on Tuesday, they had it staying around until this evening which is when the forecast ended with it (or more precisely its snow band) still stationary across Ireland.
But that forecast had the band at a 90 degree orientation to the graphic in the post above so would probably have resulted in much more substantial accumulations had it come off as was depicted.

Gaoth Laidir

tanko wrote: »

Was storm Emma forecast to be so slow moving, it hardly seems to be moving at all. Is it not supposed to head off out into the Atlantic?

It;ll get a kick up the arse this evening and accelerate along the south coast tomorrow.

IE 222

The current system running across southern England into Snowdonia seems to be heading into Emma now. Will that start to push her more towards us.

200motels

The latest radar from Rain viewer

TheMilkyPirate

Cannot imagine another 40cm on top of this in Wexford town the snow is relentless. Can someone post the latest HIRLAM can't access it on this phone.

Local service station roof has caved in and there is trees and power lines down around town as well. Snow is at 2.5ft in my back garden seen drifts around town of 5.5 to 6ft. This is once in a lifetime stuff.

jdcv94

TheMilkyPirate wrote: »

Cannot imagine another 40cm on top of this in Wexford town the snow is relentless. Can someone post the latest HIRLAM can't access it on this phone.

Local service station roof has caved in and there is trees and power lines down around town as well. Snow is at 2.5ft in my back garden seen drifts around town of 5.5 to 6ft. This is once in a lifetime stuff.

Over a meter here near Gorey 150m asl, some drifts up to 7/8ft. I don't think I'm getting out of the house for a few days at least and that's before whatever falls this evening. RTE saying that North Wicklow/Dublin would be the worst hit from the storm was a bit strange as all charts had Wexford getting pummeled.

Oneiric 3

Latest Estonian Hirlam does show a possible pep up in intensity for the Munster/S Leinster for a time later this evening:



Snowing most of the day here but not really adding to anything; and if anything, is no better than the slop we usually get. If I would be looking for some real snow next time, it will be to the north I'll be looking, and not the east.

TheMilkyPirate

TheMilkyPirate wrote: »

Cannot imagine another 40cm on top of this in Wexford town the snow is relentless. Can someone post the latest HIRLAM can't access it on this phone.

Local service station roof has caved in and there is trees and power lines down around town as well. Snow is at 2.5ft in my back garden seen drifts around town of 5.5 to 6ft. This is once in a lifetime stuff.

Hirlam for 5pm (time on it is CET).

Oneiric 3

Prep totals in the 24hr up to 3pm, based solely on radar returns.



The area NW of the Wicklow Mts is especially interesting, given that it shows hardly totals at all, yet over on the other thread, there are some epic scenes from the same region.

morticia2

Just out of interest, which (if any) of the models came closest to what is actually happening right now (snow cannon effect coming from Wales).

And what is the cause of the stall? The red/yellow high intensity precipitation there just seems to be firing stuff at us without moving itself?

FuzzyZoeller

Oneiric 3 wrote: »

Prep totals in the 24hr up to 3pm, based solely on radar returns.



The area NW of the Wicklow Mts is especially interesting, given that it shows hardly totals at all, yet over on the other thread, there are some epic scenes from the same region.

That image looks like only the radar at Shannon and Belfast is being used??

SeaBreezes

Gaoth Laidir wrote: »

It;ll get a kick up the arse this evening and accelerate along the south coast tomorrow.

Gaoith, will there be rain on the coast?

SleetAndSnow

GFS keeping the cold for a bit longer? Not as cold as now but cold for March / spring

Donegal Storm

Oneiric 3 wrote: »

Prep totals in the 24hr up to 3pm, based solely on radar returns.


The area NW of the Wicklow Mts is especially interesting, given that it shows hardly totals at all, yet over on the other thread, there are some epic scenes from the same region.

The UK radar sites have been showing that area as totally dry for the past 48 hours, seems to be an issue with the Belfast radar. The Met Eireann radar is more accurate though even that isn't picking things up right as its currently showing me right on the edge of the lightest precip yet it's near whiteout conditions when I look outside

Oneiric 3

FuzzyZoeller wrote: »

That image looks like only the radar at Shannon and Belfast is being used??

WeatherOnline uses Dublin radar imagery too. There is no reason why they would not include data from it for this image. I saw the radar last night about 1am, and there did seem to be an odd 'gap' to the NW of Wicklow.

Villain

Netweather wasn’t showing data from Dublin radar for a good while yesterday, they said the Met Office wasn’t using it due to errors

revelman

https://twitter.com/MetEireann/status/969624601415299072

sdanseo

1700Z TAFs for Dublin and Cork, cross posted from the chat thread. Feel free to correct my interpretations although I think I'm fairly confident of same.

Currently visibility at Dublin Airport is as low as 700m. Complicated 1700Z TAFs decoded below for Dublin and Cork.

TAF: EIDW 021700Z
0218/0318 08028G38KT 3000 -SN SCT008 BKN020 - next 24hrs light snow generally (exceptions below)
TEMPO 0218/0303 0800 SN BLSN OVC002 - 1800-0300 moderate snow, blowing snow, visibility 800m (nearly as bad as last night)
TEMPO 0218/0221 09033G43KT -1800-2100 wind gusting to 43kts
BECMG 0221/0223 09022G35KT - 2100-2300 wind gusting to 35kts
BECMG 0303/0305 9999 NSW - 0300-0500 no significant weather
TEMPO 0303/0312 4000 -SNRA BKN009 - 0300-1200 light sleet (more snow than rain)
BECMG 0306/0309 10018G28KT - 0600-0900 wind gusting to 28kts

For some it may be difficult to discern tonight from last night. Still a red warning although metoeroligically not a blizzard, hence the stay indoors warning not in place. Visibility while only 800m for a time would still be 400% better than at the worst point last night.

EICK 021700Z
0218/0318 05015KT 2000 -SN SCT003 BKN005 - next 24hrs light snow generally (exceptions below)
TEMPO 0218/0224 1000 SNRA BKN003 - 1800-2400 Sleet (more snow than rain)
TEMPO 0300/0305 9999 NSW 0000-0500 no significant weather
BECMG 0305/0307 10017KT 9999 NSW BKN015 - as above lower cloudbase
TEMPO 0306/0309 11022G32KT 3000 -RASN BKN010 - 0600-0900 Sleet (more rain than snow)
BECMG 0308/0311 11014KT - 0800-1100 winds 14kts
TEMPO 0309/0318 4000 -RA BKN010 - 0900-1800 tomorrow light rain

if this verifies, rebels should anticipate perhaps a sligtly faster thaw than Gerry suggested. Cork is at 500ft above the city so temps where most people live will be even higher.

Meteorite58

Looks like a steady stream of snow into the E and a large area of precipitation coming into view off Cork and heading that way.











Upper cold air getting mixed and pushed aside tomorrow.








Projected additional snowfall from 14.00 today to 07.00 tomorrow, and then the rain and sleet arrives.

stephenjmcd

When are the charts showing a slight thaw on the east ? Thanks in advance

JCX BXC

if this verifies, rebels should anticipate perhaps a sligtly faster thaw than Gerry suggested. Cork is at 500ft above the city so temps where most people live will be even higher.

The TAF's previous to it had sleet from 10am this morning which never verified.

Gonzo

stephenjmcd wrote: »

When are the charts showing a slight thaw on the east ? Thanks in advance

thaw should get going from early morning. I reckon there will be floods in quite a few areas by Sunday.

cherryghost

stephenjmcd wrote: »

When are the charts showing a slight thaw on the east ? Thanks in advance

Late tomorrow morning into the afternoon. Not a quick thaw though I think. By sundown tomorrow the melted snow will refreeze and that's more dangerous than the current problems we have

Mafra

Quick question please regarding this evening.
Radar shows a big patch sitting out in the Irish Sea. Is this due to move over us or is it as stagnant as it appears?? Thanks!!

Pangea

That met office chart showing precipitation is definitely not accurate for me in Donegal, nothing here and its showing that its snowing all afternoon!

Gaoth Laidir

Snow depths at 6 pm. Dublin, Casement and Cork are on the rise again. It's been snowing needles non-stop all afternoon in Celbridge as they formed in that inversion at around -5 °C, too warm for dendrites.

stephenjmcd

cherryghost wrote: »

Late tomorrow morning into the afternoon. Not a quick thaw though I think. By sundown tomorrow the melted snow will refreeze and that's more dangerous than the current problems we have

One extreme to the other

M.T. Cranium

Already some model discrepancy on track of dying circulation of Emma, would not be surprised if it stays off the coast and fails to advect even the small amount of warmth shown on GFS. It will be a four to five day interval of decaying easterly winds, oscillating marginal uppers for snow, sleet or coastal rain, hopefully none of it too heavy but I do see some potential for the odd resumption of 5-10 cm streamer bands (they could drop mixed showers too). At some point perhaps a grand finale event where cold makes a last stand and pushes one of these circulating lows a bit further east into southern England keeping Ireland in a colder northerly flow. Then eventually a gradual return to a more normal jet stream position and the resumption of normal service.

Will be updating forecast soon, with the latest guidance in mind. But past 24 hours I am not really going to place blind trust in any warming guidance, this snow depth will have an influence on the longevity of the sub -4 850s and that's all that is required for snow now that you aren't in Europe anymore.

Neddyusa

Oneiric 3 wrote: »

Prep totals in the 24hr up to 3pm, based solely on radar returns.



The area NW of the Wicklow Mts is especially interesting, given that it shows hardly totals at all, yet over on the other thread, there are some epic scenes from the same region.

I'd imagine most of the epic snow from that area fell on Wednesday night and early Thursday

Certainly that's the case for here west of Athlone.
We had 1ft snow on the flat and 3-6ft in drifts....but it all came from continous Irish Sea steamers and nothing fell sincé 4pm yesterday.... hence the yellow on that chart.

HONKEY TONK

Can I ask someone here what was so special about Kildare's geography that it got hammered from Tuesday to today when towns between the coast and Kildare got SFA for a large part of the time.