Wintry spell forecasting discussion - 25/11/2010 onwards

Pangea

Just a reminder to my fellow Donegal posters not to forget to vote!
Quite a miserable night out there, theres floods on the roads.

Harps

Pangea wrote: »

Just a reminder to my fellow Donegal posters not to forget to vote!
Quite a miserable night out there, theres floods on the roads.

I'm registered to to vote but too much effort to head all the way home for something that takes 5 minutes!

Very similar forecast to the last one just there but specifically mentioning snow in east Donegal will do me nicely

Redsunset

Im finally beginning to get a wee bit excited as colder air shortly begins to penetrate.

I've been working very long hours lately in North county Dublin and i expect to witness some of these lake effect streamers over the coming days.

I want to say thanks to all for posting updated latest models and very important info as i only have had my phone to keep tabs on the situation.

At the laptop now finally and can explore for myself.

Iancar29

213 People on the Weather Forum... The start of a weekend record high?

pistolpetes11

The Cold has dug in very nicely in the UK , be nice to see us like that soon.



We seem to be getting there tomorrow evening , Image is for 00.00 saturday (26 hrs time)




Image from the raintody.co.uk website

Kippure

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Things starting to shape up nicely:)

F-Stop

Harps wrote: »

I'm registered to to vote but too much effort to head all the way home for something that takes 5 minutes! lasts five years.

Anyway, back on topic, cold drizzle in Enniskerry, Wicklow. I'll post pics soon.

Harps

F-Stop wrote: »

Anyway, back on topic, cold drizzle in Enniskerry, Wicklow. I'll post pics soon.

I'm registered on an island so it'd take a 4 hour round trip which wasnt possible

Plus with the snow in the hills it'd probably take twice as long :pac:

Pangea

Harps wrote: »

I'm registered on an island so it'd take a 4 hour round trip which wasnt possible

Plus with the snow in the hills it'd probably take twice as long :pac:

Dont mind them they are just jealous :pac:

Harps wrote: »

Very similar forecast to the last one just there but specifically mentioning snow in east Donegal will do me nicely

I think she got a bit lazy when she said that , the prompter said eastern counties and donegal, and connaught , at the end she just said east donegal and counties. Hopefully it reaches all of us.

Su Campu

Here's a 12Z GFS sounding for Dublin Airport for 12Z Saturday, showing a ~350m (~1200ft) warm layer near the surface. That's a lot for snow to survive. A 900ft layer gives roughly a 50:50 chance of snow, with that probability reducing drastically with every hundred feet increase in depth. It also shows 850 theta-w around 0-1°C, which is in line with the NAE's figure too.

All of these figures would suggest snow only above about 100-150m, though with the warm layer being fairly dry, this should allow evaporative cooling to offset melting, so I'd still be edging towards the 50-100m magic height in coastal areas, sea level where showers make it inland.

It's a more or less similar situation Sunday.

oterra

Deleted User wrote: »

Ha hacketstown-it always snows there

Oh yes of course, its snow events are legendary!
As my mother used to say "you havent witnessed Cold until you've spent a winter in Hacketstown"

JFKIRELAND

Su - Stupid question time! Can you point out the warm layer? Not too sure reading these type of graphs.
Thanks
JK

Su Campu

JFKIRELAND wrote: »

Su - Stupid question time! Can you point out the warm layer? Not too sure reading these type of graphs.
Thanks
JK

The the red diagonal upwards right line at the bottom tip of the green dewpoint line is the 0°C isotherm.....if you get my meaning! The thick red jagged line is the actual temperature curve throughout the sounding, and you can see that at around a pressure of about 950hPa is crosses the 0°C isotherm and becomes positive down to the ground. The height of this positive layer is around 50hPa (ie. 50 x 8m = 400m) by eye, or maybe a little less using the table underneath.

Redsunset

Report just now on RTE 2 news to expect snow over coming days and highlighted Newcastle

greenpeter

redsunset wrote: »

Report just now on RTE 2 news to expect snow over coming days and highlighted Newcastle

That probably means we have no chance knowing them:mad:

Speak Now

2.9c and rain

dbyrne

im switching camp to the "its never going to snow" idea, im sick of looking out and only seeing rain, and hopefully to spite me mother nature gives us the pasting of a life time, e.g. 82 or 84 snow event that I can tell my daughter about when she gets older.:D

Figuramatyi

Guys, better start focusing on the storm cyclone south of England next week. All models are coming to a consensus about it, and it looks pretty freaking wild!

WolfeIRE

weather alert for NI
http://www.metoffice.gov.uk/weather/uk/ni/ni_forecast_warnings.html?from=rss&sn=2384

dbyrne

Figuramatyi wrote: »

Guys, better start focusing on the storm cyclone south of England next week. All models are coming to a consensus about it, and it looks pretty freaking wild!

Why??
Sorry for the dumb question

Figuramatyi

dbyrne wrote: »

Why??
Sorry for the dumb question

Because of these:

Temp above:
http://www.wetterzentrale.de/pics/Rtavn1202.png
temp at 2m:
http://www.wetterzentrale.de/pics/Rtavn1205.png
precip:
http://www.wetterzentrale.de/pics/Rtavn1204.png (notice the convective nature)
winds:
http://www.wetterzentrale.de/pics/Rtavn1208.png

Yep, this is a blizzard.
And while 2 days ago (when the first GFS run showed it) it had less than 1% chance to come to reality, now it's well around 50% (or over).

Rougies

Figuramatyi wrote: »

Because of these:

Temp above:
http://www.wetterzentrale.de/pics/Rtavn1202.png
temp at 2m:
http://www.wetterzentrale.de/pics/Rtavn1205.png
precip:
http://www.wetterzentrale.de/pics/Rtavn1204.png (notice the convective nature)
winds:
http://www.wetterzentrale.de/pics/Rtavn1208.png

Yep, this is a blizzard.
And while 2 days ago (when the first GFS run showed it) it had less than 1% chance to come to reality, now it's well around 50% (or over).

Shhh, it's supposed to be a suprise

NufcNavan

Should we be expecting this 'blizzard' soon?

Any chance of snow for Navan over the next 48 hours or so?

Slippin Jimmy

Could a lot of things not change in the meantime? Hopefully it will snow like theres no tomorrow, but don't want to get my hopes up!

Harps

I assume the southern half of the country would bear the brunt of that if it develops?

Would it have much effect at this end of the country?

darkman2

Snow at all levels will arrive in Leinster Saturday morning. Don't worry about the storm just yet. That will have to be tracked carefully and nailed down. It's too far out for any sort of certainty.:)

pistolpetes11

darkman2 wrote: »

Snow at all levels will arrive in Leinster Saturday morning. Don't worry about the storm just yet. That will have to be tracked carefully and nailed down. It's too far out for any sort of certainty.:)

For a cold winter weather lover let me say this :

Nout beats a darkman2 update !!!

Birdnuts

Freezing rain here earlier produced some of the most dangerous icy pavements I've ever seen - I hope its gone by the morning or skulls will be fractured:(

M.T. Cranium

The 00z GFS seems to contain a few minor upgrades, with more of a cyclonic snow enhancer for the weekend (it loops around counter-clockwise and comes back at Ireland from the east on Sunday) ... this may be the evolution of the low moving down tonight from west of Norway across the Shetlands. I'm going to be playing the forecast as a series of potential significant snow events that are bound to be somewhat hit or miss, but creating 3-5 cms of fresh snow per day where they hit ... then the Tuesday storm scenario continues about as before although there is less potential for mixing back to rain on this model run. Never thought we'd be talking about a winter storm coming up from Madeira, this is getting positively freakish as a scenario. The track of this low (which is now not far from Newfoundland) is south of the Azores, just northwest of Madeira, across Lisbon and northern Spain, into Biscay, then towards the Channel. A lot could change in that after five more days -- my guess is that if the track changes, it would be south (east) of the current track. Going back into the lab now to see what the later GFS run looks like, probably a hurricane from the Red Sea to Antwerp then Edinburgh. :cool:

Redsunset

Upgrade eh,man you gotta love that word.well if that low tracks perfectly we could be seeing snowmageddan and my winter snow prediction of 160cm could be gettin an early start. God am i startin to ramp. Too early for that yet but to say im a little bit excited is an understatement. Keep posting those latest model runs folk, you know who you all are.tis my only way of keeping up to date till i get home tonight. Thanks in advance. Here's to continued upgrades.