Cold Spell Prospects and Discussion (January + Early Feb 2012)

Harps

Just to stress how uncertain everything still is, the difference between the ECMWF and GFS this morning is ridiculous. Here's the two at 144h with totally different solutions





Looks like something might happen at some stage but I've yet to see a run where the easterly next week even reaches Ireland so a word of caution to people for the inevitable disappointment!

blackius

Don't worry about the 06Z,it must have the worst verification records of the whole lot at that timeframe.

Tune into BBC news 24 instead and see the end graphic used and what that forecaster says....


It's coming folks,it's coming.

This is no time to be calm and collected

john mayo 10

blackius wrote: »

Don't worry about the 06Z,it must have the worst verification records of the whole lot at that timeframe.

Tune into BBC news 24 instead and see the end graphic used and what that forecaster says....


It's coming folks,it's coming.

This is no time to be calm and collected

You seem very confident blackius, i hope your right, We need a good cold spell for the sanity of us snow lovers

weatherfiend

john mayo 10 wrote: »

You seem very confident blackius, i hope your right, We need a good cold spell for the sanity of us snow lovers

and for the sanity of the no-snow lovers. It might shut me up for a while.......mmmmm, maybe not!!

Musicman2000

Its really on a knife edge, we could well be on the wrong side of it by a few 100 miles, and it could go belly up for the uk as well, I have seen this happen to many times with an easterly and if this did happen, Could be some serious toys flying from prams:D

pistolpetes11

UK Outlook for Monday 30 Jan 2012 to Wednesday 8 Feb 2012:

At the beginning of the week, although there is a lot of uncertainty, eastern and central areas will most likely see clear/sunny spells, and scattered showers, these mostly light but locally wintry. Westernmost areas will probably see more cloud, with occasional rain. Temperatures will probably be below average, the cold accentuated further by fresh winds from an eastern quadrant. Towards the end of the week and through the rest of the period, a general continuation of the cold weather type seems most likely, but it is by no means certain. There is a risk of snow, ice and sharp frosts, with easternmost parts being most prone. However we certainly cannot discount the possibility that mild west/southwesterly winds will return instead, bringing rain at times.
Updated: 1225 on Wed 25 Jan 2012

UK Outlook for Thursday 9 Feb 2012 to Thursday 23 Feb 2012:

The forecast for mid-February remains very uncertain.However, the most likely outcome is for much colder weather with winds mainly from an easterly quadrant to prevail, bringing widespread frosts, and snow to some areas. In this scenario it would be the east that would be most vulnerable to snowfall. There remains an alternative scenario, in which milder westerly winds prevail, the chances of this alternative scenario are currently rated as about one in three.
Updated: 1225 on Wed 25 Jan 2012

oterra

Could one of the guys explain to me what a "short wave" is and what its effect is on weather especially whats happening at the moment.
Excuse the ignorance!

eskimocat

I know the charts are not all singing the same hymn, or are even reading from the same snow making book, but let me tell you those FI scenarios has done me the world of good today.

I know, I know, we are back in flip flop land, only this time to see which side of the fence it lands.... but still isn't it gorgeous... I believe I am recovered from early Jan enough to climb aboard the HOPE train

Come on you charts, come on you charts...

Davaeo09

eskimocat wrote: »

I know the charts are not all singing the same hymn, or are even reading from the same snow making book, but let me tell you those FI scenarios has done me the world of good today.

I know, I know, we are back in flip flop land, only this time to see which side of the fence it lands.... but still isn't it gorgeous... I believe I am recovered from early Jan enough to climb aboard the HOPE train

Come on you charts, come on you charts...

Careful now, it's a long way down


I personally have no experience forecasting but it seems as if we've been in this situation before, and look outside..

If we are to get cold I don't think it will have any sort of massive snow fall with it. With England getting the brunt of the snow this side of Europe. I can remember the snow shield parts of Ireland had last year and the year before. If we have that sort of nonsense again I'm moving to Sweeden...

Pangea

Met Eireanns forecast is a turn in the right direction
Outlook
Thursday night will be cold and breezy with further wintry showers of rain, hail or sleet and some snow on hills or mountains. Frost and icy patches will develop in sheltered areas. Friday will be cold with sunny spells and some further wintry showers in the west and north. There'll be some good sunny spells also and the showers will gradually die out. Highest temperatures of 5 to 8 degrees with light breezes. There'll be a widespread sharp frost on Friday night. The eastern half of the country will be mostly dry on Saturday. However outbreaks of rain and drizzle will affect the western half of the country and will spread further east towards evening. This rain and drizzle will linger through Saturday night, Sunday and into Monday. It will fall as sleet in places at night. Daytime temperatures will range from 4 to 8 degrees on Saturday and from 5 to 9 degrees on Sunday, mildest in the west. Rain and drizzle will become confined to western areas and then gradually die out on Monday. Tuesday and Wednesday next will be dry with good sunny spells. Current indications suggest that next week will be very cold with temperatures of just 3 to 6 degrees by day and with sharp or severe frosts at night.

pistolpetes11

oterra wrote: »

Could one of the guys explain to me what a "short wave" is and what its effect is on weather especially whats happening at the moment.
Excuse the ignorance!

http://apollo.lsc.vsc.edu/classes/met130/notes/chapter12/long_short_waves.html

Although I think I maybe a little more confused after reading that !


Sponge Bob , Redsunset , Su , DM2 anyone care to enlighten us ?

I have posted some info the the useful weather thread to try not clog up this one , cause there is lots to it !

http://www.boards.ie/vbulletin/showthread.php?p=76717896#post76717896

Rebelbrowser

eskimocat wrote: »

I know the charts are not all singing the same hymn, or are even reading from the same snow making book, but let me tell you those FI scenarios has done me the world of good today.

I know, I know, we are back in flip flop land, only this time to see which side of the fence it lands.... but still isn't it gorgeous... I believe I am recovered from early Jan enough to climb aboard the HOPE train

Come on you charts, come on you charts...

My main concerns are twofold, despite the charts looking good (GFS 6z excepted):

1. MTC is sounding a little sceptical. Not a good sign. But the bigger concern is.....
2. There's no DM2 thread!

Strangegravy

pistolpetes11 wrote: »

oterra wrote: »

Could one of the guys explain to me what a "short wave" is and what its effect is on weather especially whats happening at the moment.
Excuse the ignorance!

http://apollo.lsc.vsc.edu/classes/met130/notes/chapter12/long_short_waves.html

Although I think I maybe a little more confused after reading that !


Sponge Bob , Redsunset , Su , DM2 anyone care to enlighten us ?

I have posted some info the the useful weather thread to try not clog up this one , cause there is lots to it !

http://www.boards.ie/vbulletin/showthread.php?p=76717896#post76717896

'Shortwave Also known as Shortwave Trough; a disturbance in the mid or upper part of the atmosphere which induces upward motion ahead of it. If other conditions are favorable, the upward motion can contribute to thunderstorm development ahead of a shortwave"

Little bumpy bits in weather charts, that make more interesting bits of weather happen! Or something like that...

200motels

It's on a knife edge at the moment but my gut feeling is we'll miss out on this and be mild and mucky. I've looked at all the models this morning and they are all over the place past 4 days.

blackius

oterra wrote: »

Could one of the guys explain to me what a "short wave" is and what its effect is on weather especially whats happening at the moment.
Excuse the ignorance!

It's a fancy name for a shallow area of low pressure.

Lol at the UK met office update.
They really are in a quandry as the models are having grave difficulty with what to do with that Siberian high.
My thinking is that met office brains,ie the human input fully realise that if that thing nudges westwards to Scandi it will open the flood gates unhindered to siberia and the coldest of that air would get here by early the following week.

Basically so in their latest update they are thinking a high of that magnitude would take some shifting and they are leaving open the possibility that if it does that,the cold spell,severe at times could last into most of february.

As for DM2...I'm hoping not to see a thread from him untill sunday in the hope this won't be jinxed

pistolpetes11

200motels wrote: »

It's on a knife edge at the moment but my gut feeling is we'll miss out on this and be mild and mucky. I've looked at all the models this morning and they are all over the place past 4 days.

Id say were in the regions of 66.3% on for a good blast of cold , everything is trending the rite direction , ECM and UKMO are looking solid , The last GFS run was not great but it has been up and down more times than the undergarments of a lady of the night in the last few days/weeks.

Although the GFS in its later times frames does not look great , up to T72-96 everything seems to be going in the rite direction , if its goes wrong in that that time frame it does not have a chance of producing at a later stage

BEASTERLY

Hold on folks, ECM and UKMO are the only ones showing any sort of easterly. And a half arsed one at that with -5 850hpa's not even reaching us.

darkman2

Hi all,

Some good model output this morning re the potential for an Easterly. However I would be very cautious at this stage. It's still up in the air (pardon the pun). The UKMO and ECMWF at 144hrs are the best of the lot but even then the really cold air is struggling to propagate this far west. What we need, and there are signs on the ECM, is undercutting of troughs from the Atlantic and higher pressure to our North (an extension of the Scnadinavian high toward Greenland).

It's important to remember Ireland is the last stop on the line so to speak. It is very possible that the cold and snow will reach Britain but won't reach Ireland. But not much has to change for us to get hit proper. Right now it's more likely we are just too far west but that could change. I don't think we will have much extra certainty today.

An Easterly is on but we are not set up properly yet.

boatbuilder

Would I be right to say that the GFS got it wrong (until doing a last minute swing) about the last supposed cold spell a couple of weeks ago? Or was that the ECMWF?

*Edit* I just read back on previous posts and it was the GFS that was badly wrong only two weeks ago. So perhaps that in some way supports the value of what the UKMO and ECM charts are showing...

blackius

BEASTERLY wrote: »

Hold on folks, ECM and UKMO are the only ones showing any sort of easterly. And a half arsed one at that with -5 850hpa's not even reaching us.

I wouldn't mind that.
The lunchtime BBC forecast by Nick Millar had a front over Ireland Saturday/Sunday with lots of rain.
Nick said it would be pushed back more likely with the cold winning through.

The other thing I would say is that a lot of the model output post 120hrs is mainly speculative at the moment.
I wouldn't be expecting colder than -5 850 temps initially anyway.
This thing has to get going first and when it does,it takes a while for it to bring in deep cold assuming and I think it will,it lasts a while.

Theres another thing to consider too which is very important with an Easterly and makes it very much distinctive from say a northwesterly.

An Easterly tends to drag in cold less modified surface air with lower dewpoints.
This means it may be -6 or -7c at 5000ft but if it's also very cold closer to sea level,then you are in business.

Tom Cruises Left Nut

A bit OT but I have just realised its nearly a month since I bothered to check a rain radar.

Depressing !

weatherfiend

can I ask a slightly out-of-left-field question? Does anybody know which model accuweather use? I only ask because my iPhone app is showing 15 days of low figure temperatures and I found it very exact during the 2010 snows.

Perhaps those model runs were just more settled so it was easier to be accurate ???

Wine Goddess

My gut (and it is not insubstantial) has been telling me that Feb will be the month we'll have snow.....

And what a larf it would be to have a blizzard on Valentines' Day!
(Cue theme to Love Story.....)

Of course, my gut is not in any way linked to the ECM, GFS, UKMO, ME, MTC or any other forecasting system.

Instead my gut is a committed member of the SLAWFS (Snow Lovers Anonymous Winter Fan S)


So roll on February - do your worst best - we're ready for the snowly onslaught!:D:eek:






Well it makes about as much sense as any of the flippin' models!!!!

TheMilkyPirate

I wouldn't be getting too carried away yet, At least wait until today's 12Zs.

Actually, Wait until the snow is falling outside your door!

blackius

@ baraca I'll retweet what I said earlier...

This is no time to remain calm and collected

pistolpetes11

weatherfiend wrote: »

can I ask a slightly out-of-left-field question? Does anybody know which model accuweather use? I only ask because my iPhone app is showing 15 days of low figure temperatures and I found it very exact during the 2010 snows.

Perhaps those model runs were just more settled so it was easier to be accurate ???

Usually the latest run of the GFS , so its changes on every run of the GFS model which runs four times a day

TheMilkyPirate

blackius wrote: »

@ baraca I'll retweet what I said earlier...

This is no time to remain calm and collected

Don't tempt me to dust off my ramp!

Tom Cruises Left Nut

baraca wrote: »

Don't tempt me to dust off my ramp!

Im calling the next run early

weatherfiend

:D:D:D:D:D:D

t|nt|n wrote: »

Im calling the next run early

pistolpetes11

Just to illustrate the difference between the models ,

Here is a copy of the SLP/850 charts ,

The UKMO and ECM are nearly identical ,

Temps are nearly identical on all 3 but its the flow of the GFS and the low pressure system up towards greenland and scotland that stands out like a sore tumb compared to the other two .

Litte difference can means a lot as we go forward !

Its become a massive roller coaster , you need to be watching out for every little detail on the charts , I hope it all pays off and we get a beasterly

Also looking like a chilly enough night tonight !

GFS



UKMO


ECMWF