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

sean555

Arpege and Hirlam 12z still giving plenty of snow for Galway and parts of Mayo.arpegeuk-45-19-0.png

Snowbie

Forecasted snow depths until Friday evening.
Always will be heavier over elevation and Wicklow mtns will be cut off

bennyl10

anyone able to post hirlam from now? where is emma atm?. windy.com still has to near france

patneve2

Anyone who lives at a certain height on the eastern side of the Wicklow mts. is really in for it tonight with orographic lift coming into play you would think. Could be massive totals if the precipitation materializes later on

Oneiric 3

Appege accumulation chart up to 6pm tomorrow eve. S & E well up for it.



Blowing snow here all afternoon yet such is its nature, it isn't adding very much to what has already accumulated. Wind is beginning to feel colder and damper with the sky lowering all the time, though temps refusing to get above -1.0c. -1.5c currently with a Td of -4.0c. Pressure (1001.1 mb) falling at a steady rate.

Oneiric 3

Met Éireann 4pm reports. A lovely warm spring afternoon over the hills and meadows of fair Ogygia.

Charles Babbage

Why does the chart above #1217 show such a sharp drop from 30cm in south Dublin suburbs to 3cm in north Dublin.
Does this reflect the storm stopping there or does it reflect some sleet north of there reducing the total?

Supercell

Temperature here now 0.4 and rising, I'm wondering if there is a chance that coastal areas of Dublin like here may get snow to sleet instead of snow only later, dew point still -2.8 though but rising as well. Around 6cm of snow here, most I've seen since moving here in 2011.
Places like Roundwood in Wicklow should get awesome amounts of snow even by their standards overnight. I think my four years living in Annamoe previously has somewhat spoiled my appreciation of snowfall below epic levels!

Oneiric 3

Charles Babbage wrote: »

Why does the chart above #1217 show such a sharp drop from 30cm in south Dublin suburbs to 3cm in north Dublin.
Does this reflect the storm stopping there or does it reflect some sleet north of there reducing the total?

Take no notice of that, it is just down to grid squares (resolution of model) and the size of them.

stephenjmcd

Supercell wrote: »

Temperature here now 0.4 and rising, I'm wondering if there is a chance that coastal areas of Dublin like here may get snow to sleet instead of snow only later, dew point still -2.8 though but rising as well. Around 6cm of snow here, most I've seen since moving here in 2011.
Places like Roundwood in Wicklow should get awesome amounts of snow even by their standards overnight. I think my four years living in Annamoe previously has somewhat spoiled my appreciation of snowfall below epic levels!

personally i doubt it, still getting light showers of snow here in bray, all indications from Met are that everywhere including coastal will get getting snow

arctictree

Those charts are a bit scary for me (Roundwood, Wicklow). I'm actually thinking of staying the night in the lambing shed as its 2 miles from the house and I'm not sure if I'd get down in the morning. BTW, believe it or not, but this is the first ice day I've had at my location since I came here nearly 20 years ago.

gerrybhoy

Supercell wrote: »

Temperature here now 0.4 and rising, I'm wondering if there is a chance that coastal areas of Dublin like here may get snow to sleet instead of snow only later, dew point still -2.8 though but rising as well. Around 6cm of snow here, most I've seen since moving here in 2011.
Places like Roundwood in Wicklow should get awesome amounts of snow even by their standards overnight. I think my four years living in Annamoe previously has somewhat spoiled my appreciation of snowfall below epic levels!

Rising? It's got colder in D15 if I'm honest,utterly baltic,not stopped snowing all day and no signs of it doing so,and that's before the storm

thecommander

patneve2 wrote: »

Anyone who lives at a certain height on the eastern side of the Wicklow mts. is really in for it tonight with orographic lift coming into play you would think. Could be massive totals if the precipitation materializes later on

What height? We're on eastern side of Wicklow mountains.

patneve2

thecommander wrote: »

What height? We're on eastern side of Wicklow mountains.

Higher up like +100-200 metres. Should be bad at sea level too though

Oneiric 3

patneve2 wrote: »

Anyone who lives at a certain height on the eastern side of the Wicklow mts. is really in for it tonight with orographic lift coming into play you would think. Could be massive totals if the precipitation materializes later on

This could be akin to scenes from Arklow tomorrow!

https://www.youtube.com/watch?v=Wp8Jmq2TPW0

thecommander

patneve2 wrote: »

Higher up like +100-200 metres. Should be bad at sea level too though

145m here.

Elmer Blooker

Supercell wrote: »

Temperature here now 0.4 and rising, I'm wondering if there is a chance that coastal areas of Dublin like here may get snow to sleet instead of snow only later, dew point still -2.8 though but rising as well. Around 6cm of snow here, most I've seen since moving here in 2011.
Places like Roundwood in Wicklow should get awesome amounts of snow even by their standards overnight. I think my four years living in Annamoe previously has somewhat spoiled my appreciation of snowfall below epic levels!

-0.5c and rising too. There's ALWAYS a warm sector lurking somewhere.
These UK temperatures are quite odd? Compare Lancashire with Cornwall, and Belfast too. How the hell can the far south west of England be much colder than northern England? Answer: a small warm sector.
edit: -0.4c now. same old .................

Periscal

What about West Wicklow @ 200m.asl, should we be worried that Luq will catch our percipitation and give us crumbs? we have consistent moderate snow all day from 8AM, this is before the main event, looking at Hirlam or Aprege we are in 45mm zone, though GFS gives us barely 15mm until Saturday, who should we trust most?

200motels

Going by the latest GFS model, is there a chance that here in Waterford tomorrow it will all turn to rain.

Oneiric 3

Oneiric 3 wrote: »

Met Éireann 4pm reports. A lovely warm spring afternoon over the hills and meadows of fair Ogygia.

How did they have a rain shower at Valentia I wonder? Temp is zero and the humidity is 58. That equates to a DP of -6?

jamo2oo9

Is it just me or is anyone else's radar showing a gap over all of Dublin? I've been using netweather and rain uk radars and it shows a large band of precip over the Irish sea but stops abruptly about half way between Dublin and Wales.

FastFullBack

Oneiric 3 wrote: »

Met Éireann 4pm reports. A lovely warm spring afternoon over the hills and meadows of fair Ogygia.

Does every station report back on the hour? E.g. are all those temps as of 4PM. Or is this just the unspecified latest from each station?

Supercell

arctictree wrote: »

Those charts are a bit scary for me (Roundwood, Wicklow). I'm actually thinking of staying the night in the lambing shed as its 2 miles from the house and I'm not sure if I'd get down in the morning. BTW, believe it or not, but this is the first ice day I've had at my location since I came here nearly 20 years ago.

Best of luck M, I would bring some food and a fully charged phone too, but you probably know that already. Going to be a wild night up there, hope you are well stocked up and ready for this, you may be isolated there for a couple of days from this.

kod87

jamo2oo9 wrote: »

Is it just me or is anyone else's radar showing a gap over all of Dublin? I've been using netweather and rain uk radars and it shows a large band of precip over the Irish sea but stops abruptly about half way between Dublin and Wales.

The netweather radar has been broken most of the day, a big chunk from about dublin to offaly and south to the very north of killkenny is missing or glitched.

Gaoth Laidir

The Icon, Arome, Arpege and GFS all show a significant snow shadow west of the Wicklow mountains overnight and tomorrow morning, with reduced rates in counties Laois, Carlow, south Kildare, etc. One to watch. Meanwhile the eastern slopes should get a pasting, but soundings are now showing several degrees of low-level warming along the east a few hours after midnight, so snow should become slightly wetter at lowest levels by morning.

stephenjmcd

Gaoth Laidir wrote: »

The Icon, Arome, Arpege and GFS all show a significant snow shadow west of the Wicklow mountains overnight and tomorrow morning, with reduced rates in counties Laois, Carlow, south Kildare, etc. One to watch. Meanwhile the eastern slopes should get a pasting, but soundings are now showing several degrees of low-level warming along the east a few hours after midnight, so snow should become slightly wetter at lowest levels by morning.

Might be a stupid question but whats the difference between the snow we've had up until now and wetter snow ?

Elmer Blooker

Elmer Blooker wrote: »

-0.5c and rising too. There's ALWAYS a warm sector lurking somewhere.
These UK temperatures are quite odd? Compare Lancashire with Cornwall, and Belfast too. How the hell can the far south west of England be much colder than northern England? Answer: a small warm sector.
edit: -0.4c now. same old .................

Latest DPs still seem ok.

cherryghost

I reckon only coast fringes may see wet snow/sleet. If you check some of the models you can see the rain on the precip type chart as this warming pushes up but keeps wet stuff out into the bay/coast

It's worth noting DP in southern England/Wales before it hits us.

Supercell

Elmer Blooker wrote: »

-0.5c and rising too. There's ALWAYS a warm sector lurking somewhere.
These UK temperatures are quite odd? Compare Lancashire with Cornwall, and Belfast too. How the hell can the far south west of England be much colder than northern England? Answer: a small warm sector.
edit: -0.4c now. same old .................

Mothman's site - wickloweather.com is telling the same story and is warmer too (than here). He has a Met Eireann station in Ashford with perfect exposure (have seen it myself) so this warming is a thing, hoping it doesn't spoil the party here!

JanuarySnowstor

What I find quite odd is how little freezing there is here even though the temp is -3
You would think at that temp the snow would freeze but no