Model Output Discussion 19th January 2014-18z onwards.

[Gibby]

Good morning. Here is today's morning report on the NWP from their midnight release for today Tuesday January 21st 2014 taken from http://www.norton-radstockweather.co.uk/Model-Analysis(2859336).htm

 

All models continue to paint a changeable period over all areas for the next 5-6 days. The current area of slack winds over the UK will give way to freshening SW winds ahead of a trough which crosses the UK from west to East today and tonight. Rain and hill snow in the North will move steadily East over the UK today and tonight replacing the morning frost and fog in the East. Clearer showery air in a WNW breeze will follow to the West tonight and the East too tomorrow with Wednesday and Thursday staying showery with some heavy and thundery ones with snow on hills likely in the North. By Friday a weak ridge dampens down the showers before a further band of rain crosses East through the day. Over the weekend another spell of NW winds with scattered showers seems likely ahead of a major depression early by the start of next week.

 

GFS shows this Low pressure becoming a major role player in next weeks weather with a major feature slipping South down over the UK next week with spells of windy weather with rain and showers for all with some wintriness at times over the hills of the North in particular. Changeable weather will continue thereafter with rather drier weather across the South  for longer between the rain bands with temperatures remaining close to or a little below average in a mostly Westerly breeze.

 

The GFS Ensembles show a rather cold picture this morning mostly caused by a cold NW flow of winds from Low pressure areas sliding SE over the UK. There is unlikely to be any distinctly cold conditions but with precipitation continuing to feature through all parts of the output some of this could fall as snow at times over the hills and in the North.

 

UKMO today shows the weather next Monday with a deep Low pressure to the NW with strong Westerly winds carrying spells of rain then showers across the UK at the start of next week when it will feel somewhat cold.

 

GEM shows a very unsettled week with next week with Low pressure areas slipping SE down the East of the UK and the North Sea driving rather chilly West and NW winds with rain and showers falling as snow at times on hills and in the North.

 

NAVGEM also shows Low pressure slipping South over the UK with a wet and windy period with rain and showers and snow on hills through the middle of next week.

 

ECM is not dissimilar ending the run with a ridge of High pressure from the cold High to the NE over the UK giving rise to clearing rain and sleet away from the South after a very wet period earlier in the week and spreading dry and cold conditions SE across Britain with sharp frost and dense fog patches the likely features across Britain by Day 10.

 

The ECM 9 and 10 Day Chart shows the stalemate pattern continuing in 10 days time with the pattern of High pressure to the NE coupled with a strong Azores anticyclone together with Low pressure to the NW and a broad trough down across the North Sea and on into Southern Europe. The net result weather wise meaning further rain and showers likely moving down from the NW and becoming slow moving just to the East of Britain with periods of showery weather likely in the West under a chilly NW flow at times.

 

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

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

 

The Jet Stream shows the flow maintaining it's basic pattern though with some strengthening of the flow for a time next week responsible for the deep depression many models predict slipping South over the UK next week. In the far reaches of the run the flow may weaken again but maintain a similar position so changes in any weather pattern look very slow from this morning's prediction.

 

In Summary the weather remains in an unsettled state as the stand off continues between a cold block over NE Europe and milder Atlantic winds bumping into it from the West. The net result still favours the milder air winning out as far as the UK is concerned though things do get perilously close for very cold weather to reach our shores at times. As it stands on the models today most predict the battleground likely to be over the North Sea keeping the UK on the milder side of a broad trough maintaining spells of rain followed by showery and chilly NW winds and showers with brief drier spells when fog and frost becomes possible. The one thing to note though despite what I have just said is that it would only take small shifts in specifics to increase the prospect for cold over the UK in a much more meaningful way..we will just have to see how the models continue the battle over the coming days.

[SLEETY]

And the ec32 mean - as you were after the next 10/14 days. Probably even more decemberish than recent runs with the Azores pushing ino Europe.

who cares.The models are struggling 4 days ahead with the current setup never mind up to a month away

 

mean could be showing -20 850pa invading from the NE and nobody would give it a second glance

[KyleHenry]

Battle of the giants. ECM 0z @ 240 hours is where everything hinges on to get something really special regarding cold to the UK . The Azores High verses the Canadian Polar Vortex who will win?

[shedhead]

Just looking across the other side of the pond for a moment any pattern change looks very unlikely there right through until the end of the run.  Having already had several 3-4 day bitterly cold spells across the northeast they are now about to be plunged into a 7-10 day period of severe cold weather, which even at 240hrs looks absolutely locked in, with the next plunge already showing it's hand across NW Canada. Whilst I realise it's not impossible to get cold here when the Eastern US is in the freezer it does make things a lot more difficult, especially in light of the fact shedloads of cold fuel will continue to pour into the NE Atlantic, much as we have seen all extended Autumn so far.

 

Edited January 21, 2014 by shedhead

[nick sussex]

So do you reckon the break down of the NE Pac ridge won't work in our favour Nick? I agree that we need that low to cut-off quickly from the Altantic flow over Europe before the next re-surgence of energy from the northwest tries to keep us locked in to the same pattern. Though our fortunes may, for once this winter, work in our favour, with upstream playing ball. Still worried about the flow upstream being too strong though.

I think its  a timing issue really, so I agree we need the quickest route to the cut off low and then after that its not such a problem. If we get lucky that energy could just head se under any blocking.

[nick sussex]

Hi Nick,

The GEM develops it to some extent too http://modeles.meteociel.fr/modeles/gem/runs/2014012100/gemnh-0-168.png?00

 with a different outcome albeit still cold

http://modeles.meteociel.fr/modeles/gem/runs/2014012100/gemnh-0-240.png?00

http://modeles.meteociel.fr/modeles/gem/runs/2014012100/gemnh-1-240.png?00

The ECM is a bit better at T144hrs with a stronger high to the north and a bit more amplified upstream, we want the shortwave to deepen and engage the PV on its sw flank, this uncertainty upstream is making things difficult in terms of that clearance of energy.

[Yarmy]

Only just seen last night's JMA. That'll do:

 

 

…and 850 temps...

 

 

 

-14C just touching Eastern Scotland?

 

You'd presume it would only get better after that too. Fingers crossed.

[TSNWK]

Only just seen last night's JMA. That'll do:

 

 

…and 850 temps...

 

 

 

-14C just touching Eastern Scotland?

 

You'd presume it would only get better after that too. Fingers crossed.

Does JMA come out in the morning as well 00Z style... if so any views, sorry on phone... cheers

[Yarmy]

Does JMA come out in the morning as well 00Z style... if so any views, sorry on phone... cheers

 

Only goes to T84 in the morning. Here we are:

 

 

For comparison, last night's T96:

 

 

More robust Scandi block this morning.

[TSNWK]

Only goes to T84 in the morning. Here we are:

 

 

For comparison, last night's T96:

 

 

More robust Scandi block this morning.

many thanks - so still on track from what we can see

[Summer Sun]

Colder run from GFS again this morning below is the 8 day anomaly with only the far south west and west wales seeing slightly above normal temperatures

 

[frosty ground]

Looks rather nasty for Northern Scotland......... 

[Frosty.]

I think the GEFS 00z mean has a lot of wintry potential, don't think I have seen a more wintry looking mean since last winter / spring. It appears the uk is right on the edge of a potential freeze at around T+192 to 216 hours before a cold westerly sets in. So although I was negative last night, I do think we are in with a shout of our first, yes our first cold spell of the winter.

[Turnedoutniceagain]

^{So 'potentially' it could get colder into FI.}

^{Same forecast all Winter really}

[snowbob]

I agree frosty

Could be a case of the tide turning

I really do think that with regards of the 0z ECM this morning could be the best run we have seen this winter

( in regards to veryfying)

And the 0z have been very poor of late IMO

Roll on the 12 z

This afternoon could get exciting at last

Edited January 21, 2014 by snowbob

[Radiating Dendrite]

The GFS 6z is screaming potential to me - could see a number of surprise snow falls before a possible colder spell from the NE / East.

[legritter]

I think the GEFS 00z mean has a lot of wintry potential, don't think I have seen a more wintry looking mean since last winter / spring. It appears the uk is right on the edge of a potential freeze at around T+192 to 216 hours before a cold westerly sets in. So although I was negative last night, I do think we are in with a shout of our first, yes our first cold spell of the winter.

Yes looking at current charts next week could deliver ,i would say anyone with a few metres up and a bit of luck could see some of our elusive snow ,signs looking good further ahead as well .interesting model watching coming up especially to see where any low pressure gets pushed ,but alot riding on energy coming across the atlantic ,but if we keep those heights to our north and n/east it could get very interesting ,so here we go gang ,Fingers crossed ,Stellas on ice for now ,

[Phantom2]

looking forward to seeing the 12z roll out later, I reckon it'll show what a lot of us have been waiting to see !!

[cheshire snow]

Still looks like Thursday could be interesting for some,looks quite wintry from the midlands north

 

C.S

[MR EXTREMES]

Only just seen last night's JMA. That'll do:

 

 

…and 850 temps...

 

 

 

-14C just touching Eastern Scotland?

 

You'd presume it would only get better after that too. Fingers crossed.

and id say the jma is a good model because like the ukmo it don't go to far out so there could be some realism in the jma charts although might not transpire identical but theres certainly a possibility its around the area of these type of developments.

[SnOwFeSt]

Inexorably slow route to potential deep cold on the 6z, but some very interesting Synoptics though and big potential for surprise snowfalls after the weekend. A bit of a forecasting nightmare I would imagine with a lot of mixing between colder/ milder air masses.

Just want to see those 850s and 500-1000 heights come down a bit more and it'll be the difference between wet snow/ sleet and snow! Could be interesting in the strong winds as well!

[MR EXTREMES]

not to warm across the models today

[Dancerwithwings]

Looks rather nasty for Northern Scotland......... 

 

Your not far wrong there! Any falls of snow will be horizontal... Maybe not just for Scotland

Edited January 21, 2014 by Dancerwithwings

[MP-R]

GFS looking quite similar in terms of weather conditions felt to what the Beeb were showing on TV forecasts this morning. Squally rain early on Thursday followed by a wintry mix of showers at least making it into the western half of the country, drier and not so cold further east. Midlands northwards looks good for higher level snowfall. With regards to the outlook, it's still looking knife edge when it comes to snow and proper cold. At least in 2006, it was still cold despite not to the extent of mainland Europe and a lot drier. Rain will still be an issue after today.

[TEITS]

Inexorably slow route to potential deep cold on the 6z, but some very interesting Synoptics though and big potential for surprise snowfalls after the weekend. A bit of a forecasting nightmare I would imagine with a lot of mixing between colder/ milder air masses.Just want to see those 850s and 500-1000 heights come down a bit more and it'll be the difference between wet snow/ sleet and snow! Could be interesting in the strong winds as well!

Yes a forecasting nightmare could well be coming up.

 

Seems like we have good agreement of an E,ly as the LP sinks S. However the threat from the Atlantic will continue but with the jet aligned NW-SE these could track SE. Now the combination of cold air already over the UK plus cold NW,lys following the LP from the NW, this could bring frontal snowfalls.

 

So it looks as though at the end of the month a E vs W battle will continue but this time we look to be in a better position for snowfall.