Model Output Discussion - 10th Jan Onwards

[winterof79]

The trouble is there is no sign from any of the models of the deeper cold reaching the UK. Yeah sure we

might see a couple of rather cold, chilly days with dare I say it some air frost thrown in for good measure

and as I just posted perhaps a little wet snow here and there but I really do not think that is what people

come on this thread looking for not in January anyway.

One thing is near certain there is no trend for deep cold to affect  the UK within the next 10days.

Why not search for a colder pattern instead of deep cold.

Speak for yourself regarding the wet snow theory.Further north and east things may finally begin to get interesting given the current output.

http://www.meteociel.fr/ukmo/runs/2014011512/UW144-7.GIF?15-18

http://www.meteociel.fr/modeles/ecmwf/runs/2014011512/ECM0-144.GIF?15-0

http://www.meteociel.fr/ukmo/runs/2014011512/UW144-21.GIF?15-18 that is a decent chart.

Searching for what is not normal for the UK will inevitably lead to dissapointment.

[nick sussex]

One of the biggest snow events for many years came off this set up:

 

February  06th 1996

 

 

And the 850's

 

 

There was colder weather in mainland Europe at that time however over the UK you'll see the 850's weren't that cold, this event was the infamous one where the main snow ground to a halt to the west of London, about 5 flakes fell on me! I was living in Wimbledon at the time.

 

Just ask Steve M about this, he went to the same support group as myself afterwards to get over the trauma!

Edited January 15, 2014 by nick sussex

[bluearmy]

incidentally, the day 10 NH chart shows what could be the last piece of vortex exchange between siberia and canada for a while as the alaskan ridge helps to split the p/v pretty well. how well will the canadian segment do without reinforcements ?

[snow1975]

One of the biggest snow events for many years came of this set up:

 

February  06th 1996

 

Rrea00119960206.gif

 

And the 850's

 

Rrea00219960206.gif

 

There was colder weather in mainland Europe at that time however over the UK you'll see the 850's weren't that cold, this event was the infamous one where the main snow ground to a halt to the west of London, about 5 flakes fell on me! I was living in Wimbledon at the time.

Correct, 33cm in my back garden. It snowed for nearly 2 days non stop, air temp -1 to -2C with just a light S to SE breeze so there wasn't any modification by the North Sea in my coastal area. The cold was deep and embedded back then, its a different beast this winter.

Edited January 15, 2014 by snow1975

[bluearmy]

One of the biggest snow events for many years came of this set up:

 

February  06th 1996

 

Rrea00119960206.gif

 

And the 850's

 

Rrea00219960206.gif

 

There was colder weather in mainland Europe at that time however over the UK you'll see the 850's weren't that cold, this event was the infamous one where the main snow ground to a halt to the west of London, about 5 flakes fell on me! I was living in Wimbledon at the time.

 

i rest my case m'lud.  tbh, the modelled easterly was a surprise last week. that apart, the modelling has been trending the way the extended has been showing for a while now. 

[I remember Atlantic 252]

One of the biggest snow events for many years came off this set up:

 

February  06th 1996

 

Rrea00119960206.gif

 

And the 850's

 

Rrea00219960206.gif

 

There was colder weather in mainland Europe at that time however over the UK you'll see the 850's weren't that cold, this event was the infamous one where the main snow ground to a halt to the west of London, about 5 flakes fell on me! I was living in Wimbledon at the time.

 

Just ask Steve M about this, he went to the same support group as myself afterwards to get over the trauma!

 

bit like the one on 12th March 2006, for my location

[Man With Beard]

As many of us have mentioned, the Scandi High is a resilient beast once in place and the GFS in particular just cannot get to grips with it - here's a comparison of the forecast for Sunday 19th at T192 and T96:

I recall a few people using charts such as the T192 one above as grounds for saying the PV was ramping up again and Atlantic was going to move in quickly, but look at T96, complete turn around, the Scandi High going nowhere fast, lows dying as they approach it. Someone with more time could check but I think 75% of GFS runs in the last week have shown an imminent return of the Atlantic. The ECM may go bonkers sometimes but on the whole is a bit better dealing with the Scandi - this was its take on the 19th January at T192 and T96:

The centre of the Scandi High is pretty much the same at T192 as at T96. (Again, not enough time to check all previous charts but I think the T192 chart above is representative of other recent output). But even so, the Scandi High at T96 looks a little better around Norway than it did at T192.

 

And look what's happening to our west on the T96 chart - nothing like the Atlantic onslaught of a couple of weeks ago, even though I recall MOGREPS, EC 32dayer calling for the Atlantic train to return at the time - the amount of blue in those charts has shrunk significantly ... the hold that the PV had on our weather more or less broken? 

 

Just got to get those lows around Iceland to get split or dragged south while the pattern is in our favour.

[nick sussex]

Correct, 33cm in my back garden. It snowed for nearly 2 days non stop, air temp -1 to -2C with just a light S to SE breeze. The cold was deep and embedded back then, its a different beast this winter.

Yes it was a different scenario in terms of Europe but the set up with that sharp elongated troughing isn't impossible given the current trends, the continent cools rapidly under the right conditions.

 

 Its finely balanced between wet and cool and a bit more wintry with snow, I doubt even the UKMO know whats going to happen, its all up in the air.

[snow1975]

bit like the one on 12th March 2006, for my location

yes, another 'powder' snow event with a southerly breeze. I measured average 13cm with 50+cm drifts on the north side of the house.

[I remember Atlantic 252]

yes, another 'powder' snow event with a southerly breeze. I measured average 13cm with 50+cm drifts on the north side of the house.

 

I measured 0.00cms, stalled 5 miles to my west, bet Gnosall and places got a pasting, you not mean south side of house? wind from S

Edited January 15, 2014 by IrememberAtlantic252

[Frosty.]

Most encouraging news today is not from the gfs / ecm / ukmo etc, it's the Met office update I like,, especially from next week onwards with ongoing unsettled weather and temps close to average or slightly below. I think we will see an increasing chance of wintry ppn / ice and frost later in the month and into february, especially on hills and further north but easily the most wintry weather of the season which wouldn't be difficult since we haven't had any yet! :-)

[snow1975]

I measured 0.00cms, stalled 5 miles to my west, bet Gnosall and places got a pasting, you not mean south side of house? wind from S

No, most of the snowdrifts were on the leeward side, the north side. The wind/snow was blown through gaps in the houses and deposited in drifts to the north of the houses.

[shaky]

The ukmo and ecm charts for around 96 hours look very similar to the February 96 chart posted above also with similar uppers of -3 and -4!!do you think we can potentially get another event such as that again this weekend?flow looks slacker aswell!!

[Gibby]

Good evening. Here is tonight's look at the 12 midday outputs from GFS, UKMO, GEM, NAVGEM and ECM for today Wednesday January 15th 2014.

 

All models show Low pressure in control of the weather over the UK from now until the end of the weekend as it's position moves in close to the United Kingdom reinforced by secondary features moving within it's circulation at times. After today's mildness and drizzly rain the weather will turn a little cooler and more showery with the concentration of showers close to the windward exposures of the South and West of Britain with some lengthy drier and brighter spells at times in the NE. By Saturday a new area of Low pressure moving North over the UK could give some more significant rainfall and flooding issues in places before a return to more showery weather looks likely over Sunday.

 

GFS shows next week with the trend towards windier conditions developing later in the week with further showers and outbreaks of rain as Low pressure moves ESE across the far North and sends troughs quickly East across the UK with temperatures remaining very close to average.

 

The GFS Ensembles shows no change in the overall pattern with just a short relaxation in precipitation amounts early next week. Temperatures remain very respectable given the time of year but with little respite for those flood stricken areas looking likely.

 

UKMO tonight shows yet another Low pressure area moving ESE into Northern Ireland with fresh Westerly winds to the South bringing rain and showers across the UK yet again next Tuesday with the real prospect shown by the Day 6 chart of another quite wet and windy week being likely throughout next week too.

 

GEM shows Low pressure sinking slowly SE across the UK next week, filling slowly but taking until the very end of the run to bring any significant improvements to the wet and windy period for much of next week as a weak High pressure ridge topples down over the UK by next weekend.

 

NAVGEM also shows UK based Low pressure into the middle of next week with further rain and showers for all in average temperatures.

 

ECM is very changeable again tonight with Low pressure areas continuing to dominate conditions over the UK as they trundle down from the WNW over Northern Britain. A few drier intervals are shown on the exit of next weeks depression but the pattern shown suggests that any improvements late in the run look very short-lived.

 

The ECM 9 and 10 Day Mean Chart shows the most likely scenario in 9 or 10 days time with the UK biased towards an increasingly mobile Westerly flow between a classic UK winter pattern of High pressure over the Azores and Low pressure near Iceland.

 

http://www.wetterzentrale.de/pics/Reem2161.gif

http://www.wetterzentrale.de/pics/Reem2401.gif  

 

The Jet Stream is shown to continue crossing the Atlantic before turning South to North Africa then turning East over Europe. This general theme will continue into next week before the flow crosses the Atlantic and the UK before moving on through Europe later next week. This will probably serve to encourage more mobility of Low pressure systems and fronts through Britain rather than stalling them over us.

 

In Summary tonight at the risk of sounding like a broken record things remain very unsettled with rain or showers at times over the UK. Winds will become rather more blustery as we move through next week from a Westerly point so once more not desperately cold. There seems little evidence of yet of any major influence of the Azores High drying things out anytime soon or for that matter any push from the East so for the time being it's more of the same I'm afraid with rain at times continuing to be the biggest feature of the upcoming period.

[BlueHedgehog074]

Most encouraging news today is not from the gfs / ecm / ukmo etc, it's the Met office update I like,, especially from next week onwards with ongoing unsettled weather and temps close to average or slightly below. I think we will see an increasing chance of wintry ppn / ice and frost later in the month and into february, especially on hills and further north but easily the most wintry weather of the season which wouldn't be difficult since we haven't had any yet! :-)

Great to see the good ol' enthusiastic Frosty back.

 

Does certainly show that things aren't over yet for those after cold and snow, and I wouldn't be terribly surprised if part of that outlook from the Met Office was based on their UKMO run, although I'm guessing some of the other top-secret data not viewable to the public must be seeing something that not all the regular models are picking out on.

[bluearmy]

Struggling to understand the despondency on here. If the models were completely right beyond days 4/5, there would be little point in this thread. The trick is trying to work out where they are likely wrong and how they should be best adjusted to take all the data (current and recent) into account.Some strange postings today. will make a more considered assessment post the ecm ens. until then, consider what the overall trend has been of the last few days. (Clue: the scandi ridge is not clearing as quickly as the models keep showing it to and the disruption is correcting west, slowly but surely) and that doesn't take upstream fully into account.

 

though to say that the ecm ens are anything but progressive re the withdrawal of the scandi ridge and trough disruption is to state an untruth !  however, my theory is precariously hanging on by the spreads which retain a cluster of runs holding the disruption further west. 

[Duane S.]

I would suggest anyone interested to go and look at the buildup to the famous cold spell in November/December 2010, to see a classic example of how a real block develops - and I think that occasion IS classic. 

 

Ah, go on then, one more time... I don't think I will ever tire of watching that through frame by frame!

 

Still waiting to see the definitive cataylst towards pattern change to rear its head in the general output. No wiser tonight unfortunately. I wonder when it does (presuming it will before March is out...) whether it will be pretty sudden?

[lassie23]

High pressure in the Azores and over the eastern US is forcing low pressure from north to south, rather than west to east according to the GFS. This will leave us in cold north westerlies and possible temporary northerlies, according to the GFS. There is wintry conditions in there for the north, not so much for the south.

[damianslaw]

Reliable timeframe we have a col set up forecast tail end of the week - ooh its a long time since we have seen one of them, with strong heights to our NE and SW and low heights to our NW and SE on Sunday into Monday - such conditions in mid winter often mean a cold day with slack conditions and lots of fog, so something different to look forward to. At the 96 hr timeframe we really aren't far off a cold set up, but alas the troublesome trough to our west is going to be forced eastwards by energy off the eastern seaboard and the Greenland vortex - I said a few days back an amplified flow is required to bring in a colder continental set up but the models aren't suggesting this.

 

In normal circumstances the set up is ripe for undercutting and the trough to disrupt - but instead the models just want to keep it in situ. Low pressure to our NW has been a theme for so long now..

[damianslaw]

One of the biggest snow events for many years came off this set up:

 

February  06th 1996

 

Rrea00119960206.gif

 

And the 850's

 

Rrea00219960206.gif

 

There was colder weather in mainland Europe at that time however over the UK you'll see the 850's weren't that cold, this event was the infamous one where the main snow ground to a halt to the west of London, about 5 flakes fell on me! I was living in Wimbledon at the time.

 

Just ask Steve M about this, he went to the same support group as myself afterwards to get over the trauma!

 I've commented on this event before, it delivered the heaviest snowfall to these parts in the last 30 years at least. We ended up with 18 inches with snow non-stop for 36 hours. I remember the forecasts calling for a shorter wet snow event, but as the event arrived it was clear the trough was going nowhere fast and did one of those rare things but stall and retreat westwards. It was a very similar event to 12 March 2006.

 

I also suggest people take a look at some of the charts from mid-late Feb 1994 where we saw battle between the atlantic and continent and a number of occasions when the atlantic lost against the continent delivering decent snowfalls to many under not particularly cold uppers. I do think February is more likely than January to see the continent win the battle against the atlantic, and March even more so...

 

Sorry for reminiscing, but it is worth discussing how in the past a similar synoptic set up to what we have now has ended up in trough disruption with the continental high winning out against the atlantic - alas though this year we have a rampant PV at levels not seen for a long long time.

[Skyraker]

You're joking the only thing remotely interesting is the Scandi high, any brutal cold in the USA is going nowhere unless you can cement over the Atlantic Ocean,

 

Funnily enough I know a couple of travellers who'd give you a quote on that.

[nick sussex]

The GFS at T48hrs continues to correct the pattern a little further west over the USA, these small changes may make a difference as the crucial trough disruption and how far west/east this is occurs later in the output.

[karlos1983]

Certainly is further west

12z

18z

[Purga]

though to say that the ecm ens are anything but progressive re the withdrawal of the scandi ridge and trough disruption is to state an untruth !  however, my theory is precariously hanging on by the spreads which retain a cluster of runs holding the disruption further west. 

The ECM mean is clearly showing the block being pushed back way to the east

 

The strength of the intensifying vortex to the NW and the bulging Azores HP is too much to resist. I think it's game over for any proper cold let's face it.

What Februaury may bring is another matter.

Edited January 15, 2014 by Purga

[Jason M]

Might squeeze a frost on this run :-)

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=120&mode=0