Winter Model Discussion 18Z 3/2/13 onwards.

[SMU]

Thats a huge statement to make Steve seeing as my taxpayers money pays for the UKMO.....Well at least 0.00001 of a pence does ....

Without seeing the output day in day out then id be very cautious of that.

Regards

no your right I am making assumptions- these are-

Ians commentary what he said they showed then 10 or so days later the actual output.-

However the sample size isnt great.

S

[Tamara]

Forgetting the hunt for snow for a minute but again we see heights over Russia, Scandi again this Winter......no GH but heights East North East...riskier solution but rewards can be great......

We know from exactly (almost to the day) 22 yrs ago this can be especially true. But these are rare and whilst nothing like that is likely to happen this time around, if we get the trough in the right place later this weekend and something of an easterly afterwards then many places around the UK would be happy with that.

[Frosty.]

indeed peter - its very gfs 12z like at day 4

And then it got better, much better

Even when it looks a bit dodgy for the west/nw, the ecm 12z cold block fights back again at the end. How much longer will the gfs look so clueless compared to ecm.

[SMU]

Yes but it's a gradual game over from T168 once you see where the energy is going and milder for all by day 11.

Not that that matters hugely at this stage as the earlier timeframes are still to be decided.

Milder day 11 ian.

Not so.

remaining mild for the NW & Ireland-

http://www.meteociel.fr/modeles/ecmwf/runs/2013020412/ECH1-240.GIF?04-0

ECM queuing up another undercutter so for england very cold with severe frost.

S

[Methuselah]

IMO, all this talk about 'retrogression' is getting a bit thin: so far, there's been no sign of it...

[MR EXTREMES]

im not normally against the ecm but look at these two charts.

t96 ecm

then the very next frame t120

its a mega turn around looks odd not disputing how exciting the ecm is just seems to be moving along very very fast.

[weather eater]

Firmly FI, but the Atlantic certainly isn't getting very far at T240

No and the ECM is still keen on moving the lobe of the PV away from Greenland this should help if we want to see something a bit more memorable than what we have seen projected the last day and a half. One step at a time but what we want is to see some of the more potent charts the ECM was showing a couple of days back, short of the slider low, the ECM looks pretty cold if dry for most at the moment, but as TEITS has alluded to there is no real point getting hung up about post the mid range, ECM trumping the GFS and the slider low first and that’s nowhere near a done deal.

[ChartViewer]

We know from exactly (almost to the day) 22 yrs ago this can be especially true. But these are rare and whilst nothing like that is likely to happen this time around, if we get the trough in the right place later this weekend and something of an easterly afterwards then many places around the UK would be happy with that.

Yes a stunning evolution Tamara -15 isotherm Feb 1991........Those risky but so rewarding synoptics are so rare today....What interests me and one for the experts is with any SSW we havent seen any form of GH all winter but have flitted around ScandI heights but got some ok rewards......Hope the ECM continues to be bullish over next 2 days

[winterof79]

Well ECM sticking to it's guns in the semi-reliable, a shadow easterly at day 7. Atlantic back at T192 ?

Forgive me for asking but what in the Atlantic http://www.meteociel.fr/modeles/ecmwf/runs/2013020412/ECH1-192.GIF?04-0

[Tamara]

Yes a stunning evolution Tamara -15 isotherm Feb 1991........Those risky but so rewarding synoptics are so rare today....What interests me and one for the experts is with any SSW we havent seen any form of GH all winter but have flitted around ScandI heights but got some ok rewards......Hope the ECM continues to be bullish over next 2 days

I think we blame the big bad Canadian vortex It remained stubborn after the SSW split. Interestingly the stratosphere charts on the ECM continue to model a slight warming of that vortex section over Canada and I've been wondering the last day or two if this is one of the factors that is supporting its persistent modelling of the jet stream and troughs across the atlantic that amplify things more favourably for us as the model keeps showing

Edited February 4, 2013 by Tamara Road

[lord stratus]

Forgive me for asking but what in the Atlantic http://www.meteociel.fr/modeles/ecmwf/runs/2013020412/ECH1-192.GIF?04-0

It's the sort of post that annoy me most, looking for the end of a cold spell before it's even begun!

[bradymk]

http://www.yr.no/sted/Storbritannia/England/Birmingham/langtidsvarsel.html just to reinforce how the atlantic makes no inroads into most of the UK throughout the run, here are the 2m temps for a central location in the UK. Very cold and frosty and showing the snow event for central UK sunday.

[Jason M]

GEFS are a complete mess tonight. Even at day six I would go as far as saying there is no discernible trend.

Jason

[Mucka]

No and the ECM is still keen on moving the lobe of the PV away from Greenland this should help if we want to see something a bit more memorable than what we have seen projected the last day and a half. One step at a time but what we want is to see some of the more potent charts the ECM was showing a couple of days back, short of the slider low, the ECM looks pretty cold if dry for most at the moment, but as TEITS has alluded to there is no real point getting hung up about post the mid range, ECM trumping the GFS and the slider low first and that’s nowhere near a done deal.

Excellent post.

The most important thing is to have that slider low move down the Western flank of the UK thereafter is FI.

That said we really need to see a more amplified pattern behind it if we want see anything more than chilly and dry with a slow erosion of the block from the NW and see something more in line with Saturdays output. If we are left hoping for the block to hang on with all the energy heading NE over the top and a magical undercut beyond FI to renew the pattern we will likely be disappointed.

So yeah, let's get some consensus on the slider first but hope for more amplification behind to set up a more secure, prolonged cold shot with enhanced snow chances.

Edited February 4, 2013 by Mucka

[Ryan Dutch Weatherman]

ECMWF is amazing end consistent.

I never believed in strong Atlantic.

Also cold marc will follow up i think.

[Panayiotis]

im not normally against the ecm but look at these two charts.

t96 ecm

then the very next frame t120

its a mega turn around looks odd not disputing how exciting the ecm is just seems to be moving along very very fast.

No its not,within 24hrs a lot can change when it comes down the weather, that low SE of Greenland is sending warm air into the Scandi region = building of heights within that area.

[ANYWEATHER]

Gfs is really struggling with this one, Ecm has been outstanding in its consistency in its cold output, looks like some very interesting model watching at the moment!! The charts to show you what I mean!!!

[Frosty.]

It's the sort of post that annoy me most, looking for the end of a cold spell before it's even begun!

cold spell began today actually, in the north at least. lots of met office snow/wind warnings and barely a comment about it. It's to be hoped the ecm stays on track after all this drum roll build up.

Edited February 4, 2013 by Frosty039

[Gibby]

Good evening. Here is the latest look at the 12z output from GFS, UKMO and ECM for tonight Monday February 4th 2013.

All models show a cold and showery few days with the air cold enough for some snow to all levels even in the South as Low pressure moves ESE then South-east through the North Sea over the coming 48 hours. The Northerly flow weakens quickly later in the week with a disturbance toppling SE over the UK later on Thursday or Friday with some rain or sleet in places. A ridge of High pressure then develops over the UK with a few days of cold and frosty weather by night and some pleasant sunshine by day.

GFS doesn't share a fine weekend with milder Westerly winds and some rain moving East over the British Isles through Saturday and Sunday. Thereafter an unsettled and windy spell sets up with Low pressure to the North and High to the South with strong winds and rain alternating with rather colder more showery conditions.

The GFS Ensembles show a return to the ensembles of yesterday with a cold interlude this week before things return to nearer to normal under an unsettled and Atlantic based pattern with rain at times and temperatures close to average. there will be plenty of rain about. The operational was a milder option than most for the South of the UK.

The Jet Stream continues to topple down over the UK from the North over the coming days before the flow weakens temporarily at the weekend before the flow retruns from the west over the UK.

UKMO for the weekend shows a push of Atlantic air moving in from the West with rain and hill snow moving slowly East across Britain in rather cold conditions overall.

ECM shows a similar pattern at the weekend to UKMO with the system bringing the rain and hill snow slightly further West meaning more areas in the North and East may more likely see some snow as the milder air fails to make it across on this occasion. The weather then settles as High pressure builds across the UK with some cloudier zones when a little rain could fall. There would also likely to be some overnight frosts and contrastingly bright conditions by day.

In Summary the weather looks becoming more benign from the Euros after the windy, cold and wintry weather of this week. High pressure looks like building across the UK behind next weekends disturbance. GFS though is much more progressive with rain and strong winds becoming resident for all from the weekend. There has been a shift in the operationals away from anything significantly wintry tonight and that includes the GFS Ensembles too so the most likely outcome if cold is to survive over the UK beyond the weekend is for a generally dry and anticyclonic pattern rather than a snowy one.

[Stu_London]

Thanks Gibby

Good summary which gives some perspective against some of the ramping going on in here.

[Dexter29]

Thanks Gibby

Good summary which gives some perspective against some of the ramping going on in here.

I was just thinking the same, Gibby's Summary going for a rather Benign anticyclonic period after The weekend and a general dry theme. (Not snowy)

Bit different from some of the other posts in here.

For a learner it makes it very confusing!

Edited February 4, 2013 by Dexter29

[Frosty.]

Thanks Gibby

Good summary which gives some perspective against some of the ramping going on in here.

It's not ramping though is it? not when the Ecm continues to show a cold outlook as it has done for several days in a row.

[chris55]

http://www.yr.no/ste...tidsvarsel.html just to reinforce how the atlantic makes no inroads into most of the UK throughout the run, here are the 2m temps for a central location in the UK. Very cold and frosty and showing the snow event for central UK sunday.

This site was a great find, I bookmarked it yesterday when Nick posted a link. You can even get your home town on it (in English). I am assuming it is the RAW ECM data that it runs off?

[ANYWEATHER]

Thanks Gibby

Good summary which gives some perspective against some of the ramping going on in here.

Stu,yes right but I do feel that in this synoptic situation there could well be some nice surprizes for the coldies....and some other extreme weather cant be rulled out locally....

[Frosty.]

I was just thinking the same, Gibby's Summary going for a rather Benign anticyclonic period after The weekend and a general dry theme. (Not snowy)

Bit different from some of the other posts in here.

For a learner it makes it very confusing!

well just to clear this up, the ecm is currently showing a snowy weekend and a very cold spell extending through next week, especially further south and east, widespread sharp frosts and some snow flurries/showers.

Edited February 4, 2013 by Frosty039