Jan-Feb : The model search for more cold

arctictree

arctictree wrote: »

The ECM 12UTC looks good for cold/snow showers on Friday. Even shows a little LP in the Irish sea!

http://www.ecmwf.int/products/forecasts/d/getchart/catalog/products/forecasts/medium/deterministic/msl_uv850_z500!Wind%20850%20and%20mslp!120!Europe!pop!od!oper!public_plots!2008012712!!chart.gif

A lot of time between now and then though...

Trouble is that will have formed in the Irish sea or off the north Coast and will slide into the Irish sea.
The wind is Northwest remember and that will be taking stuff north of you away from you.

That said,I wouldnt be dispondent,it could be very showery even in the East(that kind of detail is only speculative untill about thursday Im afraid!) I'd be very confident though that precip everywhere will be snow if we have close to -40c at 500mb and circa -8c at 850mb and sub zero dewpoints.
*if the NWP output of today is to be relied upon*

Kippure

Shower activity will be important, remember last time, donegal got 4 inchs from an easterly!!!


With such a cold flow, polar low formation will be very possible.


Plenty of troughing and prolonged snow hopefully.

ninebeanrows

I post a chart from the 18z @ 108hrs.

I have never ever seen such a storm progged and personally would not want it to happen.

As it would actually devestate large swathes.

darkman2

Any snow on Friday would surely lead to blizzards - showers or not. This run is stretching credibility though.

Scubadevils

Why, what would it be if it panned out as indicated in the models?

darkman2

Check out the 510DDAM line and the troughs waiting in the wings:eek:

Rofl at all that.
All nice and Dandy by the way North of that line from Dublin to Galway.
Probably dandy enough too south of that line.

The synoptics described above(and in particular a 950mb storm upon which they are hinged inc the depth of the cold and strength of the wind) have as much chance of happening as my Grandad cyling on a unicycle down the stairs here tonight without once falling off his bicycle.
I might add that My Granddad died in 1984 R.I.P.

arctictree

I think the GFS 0z is an upgrade. Winds are more northerly on Friday morning and cold spell is lasting well into the weekend....It all hinges on the charts now in the next few runs....

A

The minus 40 500mb air is good for shower generation in the North Irish sea but theres only one place they are headed though in a northwesterly and it's not Roundwood unfortunately,it will be Llandudno which in theory at sea level could get 5 or 6 inches nevermind what falls up on snowdonia!

The best the East south of Dublin can hope for are showers that have travelled across the land from the northwest by which stage they should be considerably weakened-thats if many if any get that far at all.
The best you can hope for is a shallow low to track down the Irish sea which would disrupt the NW wind flow but retain the super cold air.
That low would inevitably also be heading towards wales (good for them being plastered with more snow) but it might drag showers in for a visit to Wicklow or wexford on route.

Looking sweet on this run again next w/end for the likes of Galway mayo,Sligo,Roscommon,Leitrim and all of Ulster and North Leinster aswell as West Munster.

ninebeanrows

I think Ya'll like this chart Black Briar!!

Lets hope the NNE/NE trend continues.


Going to be incredibly cold Friday/Saturday/Sunday for sure, probable ice days for many.

maquiladora

This would be nice wouldnt it?

Netweather snow risk chart from the 06Z GFS.

The pink area is classified as "100% snow risk".....

arctictree

The current series of GFS charts from t+96 are amazing. Cold northerlies, followed by easterlies. Hope this is all not just a big disappointment!

A

rc28

My mocks start tomorrow and last into next week. It would be a dream come true if I "couldn't make it in" to maths or irish on friday and next monday
I have a vague memory of this time last year when wc was in the same position as me, i think a good bit of snow was forecast but it only fell as rain. I hope we're luckier this time.

rc28

From the met this morning;
"Temperatures will fall sharply again Thursday evening as the winds veer west to northwest. The rain will clear to showers, but the showers will turn wintry and may well give a covering of snow in many areas. The winds will have eased a little by Friday, but will be coming from a bitterly cold northwest direction. There will be some bright or sunny periods and occasional hail, sleet and snow showers, some of the showers heavy and possibly thundery in places, especially in the west and north of the country."

darkman2

Thursday night into Friday looks very interesting atm but carries a health warning.

Villain

Oh Stokholm looks cold this week, knowing my look Ireland will get a snow event the one weekend I'm in Stockholm !!!

lucernarian

This weather model malarky looks very bizarre indeed. I can't tell for love nor money what looks the most likely. I do think though that it's the coastal areas from Mayo to Antrim that will be deluged in snow, with not much to spare for anywhere else.

I've seen these synoptics before, though none so violent, and I haven't seen them ever delivering for Co. Louth anyway. March 07 had an inch for an hour or so, though that was lucky positioning for inland showers.

I'll be in Tipperary this weekend, so I might catch a polar low or suchlike down there.

Weathercheck

Weathercheck wrote: »

I think Ya'll like this chart Black Briar!!

Lets hope the NNE/NE trend continues.


Going to be incredibly cold Friday/Saturday/Sunday for sure, probable ice days for many.

Oh that would push down the daffodills alright
It would pelt snow into the East,the stuff that would otherwise be going into Wales.
I have my doubts though as it's one run and the NNE element is highly dependent on where that scandi low goes.
heh I never expected to be speculating on snow in the East dependent on a Scandi low.
That chart by the way is almost jan '87 in nature except the atlantic high is a bit further northwest and pivoted slightly worse.

nacho libre

darkman2 wrote: »

Check out the 510DDAM line and the troughs waiting in the wings:eek:

holy cow there is a very good chance of a polar low based on that. if that happens even Cork will get some snow.

nacho libre

nacho libre wrote: »

holy cow there is a very good chance of a polar low based on that. if that happens even Cork will get some snow.

I have no doubt that inland cork will see snow in the thurs-fri northwesterly as it will see heavy showers in off the atlantic in near zero at times air temps (2-5c anyway) with negative dew points.

Paddy.1

nacho libre wrote: »

holy cow there is a very good chance of a polar low based on that. if that happens even Cork will get some snow.

I just have one little concern about that chart in that it shows a very slack airflow over Ireland, which would indicate that showers would struggle to get inland due to the lack of any wind to drive them in. Of course that chart may change, but going from that one alone, it would seem that Cork, Kerry, and the coastal fringes of the north and west would have a some sort of chance of getting a dusting.

Looking forward to later runs.

Rain showers seem to penetrate well inland down there, into west cork anyhow in slack enough flows so I'm not so worried.I've been well drenched often enough down there to know this :(:(

Though I'd have to repeat too that later runs are the key,I'll be watching the TV forecasts on wenesday and thursday and friday for some depthive analysis...(unless it's Gerry Murphy).

arctictree

I think this is the updated one:



Nice LP forming off the west coast...

A

nacho libre

Paddy.1 wrote: »

I just have one little concern about that chart in that it shows a very slack airflow over Ireland, which would indicate that showers would struggle to get inland due to the lack of any wind to drive them in. Of course that chart may change, but going from that one alone, it would seem that Cork, Kerry, and the coastal fringes of the north and west would have a some sort of chance of getting a dusting.

Looking forward to later runs.

Do you mean the trough shown off the northwest coast would fizzle out inland due to the slack winds?

nacho libre

arctictree wrote: »

I think this is the updated one:



Nice LP forming off the west coast...

A

i hope if that happens the lp does not decide to move eastwards across Ireland.

lucernarian

Lol you're possibly the only person on this forum who would not want it going eastwards!

Only one thing is certain: what happens on Friday will not be the same as that Met Office graph. Lots of variables to work out yet.

arctictree

Not often though that you see a HP stretching from Greenland to the Azores. Hopefully the charts will build on that...

Paddy.1

nacho libre wrote: »

Do you mean the trough shown off the northwest coast would fizzle out inland due to the slack winds?

That is just one possibility, although nothing is set in stone just yet. The models are very complicated at the moment. As the post above says Met office chart may end up not verifying anything like that. I tend to look on the negative side of things so don't lose hope yet. Will be interesting to see how models pan out over the next couple of days. Certainly a lot of uncertaintly even within the 'reliable time frame' at the moment.

I think one thing is looking certain though, is that it is going to feel cold.

hawkwing

Latest MET.ie
It will be cold on Wednesday, with temperatures rising no higher than 4 to 8 degrees at best in the strong west to southwest winds. There will be some bright or sunny periods early on, but showers will become fairly widespread during the day - showers of hail or sleet likely, with a possibility of snow in places, especially on high ground. There will be a temporary rise in temperatures on Thursday, but it will be a very windy day, with outbreaks of rain. Winds strong to gale force southwest, with some severe gusts. Temperatures will fall sharply again Thursday evening as the winds veer west to northwest. The rain will clear to showers, but the showers will turn wintry and may well give a covering of snow in many areas. The winds will have eased a little by Friday, but will be coming from a bitterly cold northwest direction. There will be some bright or sunny periods and occasional hail, sleet and snow showers, some of the showers heavy and possibly thundery in places, especially in the west and north of the country.

lucernarian

The 12z GFS operational run is upgrading the 850 hPa temperatures anyway. Jury's out on the LP positioning in Scandanavia.

Most notably, the Greenland High is not so intense on Friday night. Precipitation also upgraded somewhat, though once again this benefits the north and west coasts almost exclusively.

Dew points are seriously impressive. Any precipitation on friday will be snow based on that run.

And to end the post on an even higher note, the t+108 chart has sub 510 dam air over much of north Ireland including Dublin.