Model Output Discussion

[Thundery wintry showers]

The northerly shown on the GFS is quite potent for the time of year, but still, I think those overnight minima are being overblown just a touch. We saw the same thing happen with GFS at intervals during the winter as well.

But fair play to GFS for latching onto this "northerly" scenario before the UKMO/ECM. ECM did show it earliest of all, but it then had a big wobble at the same time as the GFS picked up on it. Indeed, I recall from my model output analysis a couple of years ago that GFS handles northerlies best of all- trouble is it is also more prone to "handling" phantom northerlies that never transpire!

[SP1986]

It looks like the northerly is definitely on the cards but it's how prolonged and intense it will be thats is the question. There no point about the fact the GFS predicts -17C and I hope sincerely this will go some way to prove to people how dubious the GFS temperature can and have been.

It looks like a sunshine and showers northerly to me though! Which is good

[reef]

Will the GFS be showing these types of charts in July and August - I wouldn't bet against it, in fact I imagine it could be quite a good bet :lol:

http://www.wetterzentrale.de/pics/Rmgfs1684.gif

That would be a new low record for April. The current low minimum is -15.0C in Newton Rigg, Cumbria, back on 2nd April 1917.

Unlikely to happen Id say.

[MR EXTREMES]

That would be a new low record for April. The current low minimum is -15.0C in Newton Rigg, Cumbria, back on 2nd April 1917.

Unlikely to happen Id say.

i would not bet against it.

april 2008 was fairly potent cold event bringing lying snow here on the southcoast.

and if you look at 1917 if im correct this also was a solar minimum time,infact solar activity has dropped away again after what was looking like a major ramp upwards.

but this minimum is on par with 1917.

its also been a pretty cold winter,

and its very possible it could get close to the record.

plenty of deep cold bottled up around the arctic areas to.

but key to all this is where low pressure goes even so great thundery shower yesterday and true spring mix on the way bring it on.

gfs been pick of the pack and as i expected the ecm jumped onboard lastnight.

:lol:

[Thundery wintry showers]

I doubt that minima below -10C have ever been recorded near the Tyne and Wear coast in late March/early April as the GFS implies. Cleadon managed it earlier in the season, on the 3rd March 2001, but by this time of year, minima of -10C and below should be reserved for prone frost hollows.

[Eugene]

Shocking GFS 12Z run for warm weather fans, looks very cold and wintry next week, starting as rain on monday but increasingly turning wintry on monday night into tuesday esp midlands northwards then cold with wintry showers rest of the week, brrrrrrr.

[londonsnow]

very wintry 12z. lets wait for the daily express to cotton on...

[NorthantsSnow]

This is quite a chart for midday Tuesday! A touch more significant than just a few wintry showers:

http://charts.netweather.tv/gfsimages/gfs.20100326/12/96/prectypeuktopo.png

Winter doesn't want to let go - and nor should it. :lol:

[MR EXTREMES]

I doubt that minima below -10C have ever been recorded near the Tyne and Wear coast in late March/early April as the GFS implies. Cleadon managed it earlier in the season, on the 3rd March 2001, but by this time of year, minima of -10C and below should be reserved for prone frost hollows.

certainly trending cold nothing would suprise me.:lol:

[snowmadchrisuk]

The Gem is not keen at all on bringing them Cold 850's in quicker instead prefering 850's over England of 0 deg on Tuesday , This will probably be a more realistic forecast given how deep the low is it is bound to have a massive warm sector associated . On top of this the air is already very Mild over the Uk. Cold air will filter down after the low has passed and then it looks more of a case of Showers in the day but will be more Wintry than pure Snow as they will be falling in the afternoons . I am not saying everywhere will miss out and it is a bit far ahead to firm up but this seems about right for England , Scotland on the other hand is alot Colder so they will just need the precipitation .

[Geordiesnow]

However Chris, the low on the UKMO is less deep thus i would imagine there be more cold over the UK and the mild sector being less of an issue. The GFS shows that you can still have a slightly deeper low and cold air over you but you don't want the low to travel too far North otherwise it would bring the milder in from the south before the cold air digs in behind.

So the position and strength of the low is vital and could make a difference between heavy rain and heavy snow.

I disagree with those who says the showers will be "wintry" because of the time of day, remember the GFS temp charts will show higher temps due to the strength of the sun, in any showers, i would imagine the temp would drop to quite close to snow flake falling levels. The heavier the shower the better of course.

[snowmadchrisuk]

However Chris, the low on the UKMO is less deep thus i would imagine there be more cold over the UK and the mild sector being less of an issue. The GFS shows that you can still have a slightly deeper low and cold air over you but you don't want the low to travel too far North otherwise it would bring the milder in from the south before the cold air digs in behind.

So the position and strength of the low is vital and could make a difference between heavy rain and heavy snow.

I disagree with those who says the showers will be "wintry" because of the time of day, remember the GFS temp charts will show higher temps due to the strength of the sun, in any showers, i would imagine the temp would drop to quite close to snow flake falling levels. The heavier the shower the better of course.

Agreed but you also have to remember we need the low to be as deep as possible as it is this that will be dragging the Cold air in . We will have to agree to disagree on the Shower situation , although I will say it will be hit and miss. High areas such as Derbyshire and places like Buxton will do very well. Settled Snow is Highly unlikely unless it falls at night and this will melt Very quickly in the Mornings. (The clocks going forwards may actually help us in that situation )

[Eugene]

I think you mean GME chris as GEM 12Z isnt released yet, GME is not the best of run so i wouldnt get too hung up on that run, the ensembles show quite a few colder runs than even the OP for monday into tuesday, the risk if there for disruptive snowfall almost anywhere even as it starts as rain it could easily turn to snow on tuesday as the colder air is pulled southwards.

Also geordiesnow is spot on it doesnt matter what time of day it is, temps will plummet under any showers.

[D KARLSON]

Very difficult to predict how this cold spell will pan out, its certainly a case of how cold ,prolonged and how much snow decends to lower levels.

One factor that cannot be overlooked is the previous cold winter, which has lowered sst ,s to our north and east and also the residual cold air that still sits over Scandinavia ,this will allow the air dragged in to be that bit colder than it would otherwise be and these synoptics have the potential to produce some quite widespread snowfall even for low ground.

details are going to be hard to pin down, but the the potential is certainly there !!!!!!!!!!!!

[Cheese Rice]

GFS is a great run, glad to finally see some more wintry weather. Monday/Tuesday looks like a nightmare to predict, the GFS has been fairly consistent with the track of the low with the northern most of extent been North East England. The highest risk of disruptive snowfall looks to be Yorkshire and North West England, then most of England looks to be seeing some snow form this low as it clears with the potential for some heavy snow over Midlands and South East England. I will wait till the NAE comes out tomorrow and hopefully will have better idea of where it will snow.

From a IMBY perspective I think I am in prime position for some decent snowfall.

Any chance of the regional threads going back up?

Edited March 26, 2010 by 10123

[Ben_Cambs]

GFS is a great run, glad to finally see some more wintry weather. Monday/Tuesday looks like a nightmare to predict, the GFS has been fairly consistent with the track of the low with the northern most of extent been North East England. The highest risk of disruptive snowfall looks to be Yorkshire and North West England, then most of England looks to be seeing some snow form this low as it clears with the potential for some heavy snow over Midlands and South East England. I will wait till the NAE comes out tomorrow and hopefully will have better idea of where it will snow.

From a IMBY perspective I think I am in prime position for some decent snowfall.

Any chance of the regional threads going back up?

Some times LP's arent fully agreed on until T+24, or even less than that in one case for my location this winter. On the 21st Feb one NAE run predicted rain for me with the concentration of snow in the Midlands, yet in the next run it shifted much further south and then I was in the position to see snow for the next day and I did. Im not telling you this from a IMBY point of view So you shouldnt start to get confident until within T+48, otherwise you may be disappointed. So all I'm saying be cautious and aware of the next few runs and if it is still showing within T+48, then you should get confident, then very confident within T+24.

[Frosty.]

After the recent and current bore fest weather conditions, next week is looking more interesting with a cold arctic plunge from the north but with scotland seeing the most wintry showers and frosty nights whereas low pressure further south will complicate matters with a wintry mix of cold rain, sleet and snow although the wet snow is more likely on hills. The GFS 12z is a pretty wintry run for this time of year but it is probably over egging the wintry potential a bit but we shall see, a bit of a sting in the tail of march and start of april. :lol:

[cooling climate]

The ECM is again the party pooper tonight. There is pretty good agreement between the

GFS and the UKMO model with regard to the track of the low t96-120 where as the ECM

takes it much further north.

You can not just dismiss the ECM run but the model has been the last to come on board

with this much colder outlook. Is it the model to follow or is it just playing catch up.

[The PIT]

ECM flips again seems to flip every run these days. GFS still icebergs at dawn. Surprised the thread is so quiet.

[frostyjoe]

ECM flips again seems to flip every run these days. GFS still icebergs at dawn. Surprised the thread is so quiet.

yea i can see why they are not on now.. this is only going to be a sleety spell of wet snow and temps around 4c with no frost due to cloud and it will be back to 9c on wednesday.....

[ANYWEATHER]

It does indeed look like the Uk is going to return to Winter next week....Gfs has painted this picture for a few days now and it makes a change for it to put out a stable forecast considering the synoptics ,Ecm on the other hand is behaving very poorly and really should be binned! Note too ,that the Met Office have a similar synoptic evolution regarding Tuesday as the very cold uppers tuck tightly on the Northwestern side of the low pressure ,with a rain to snow scenario. As ever with these synoptics things will change, but broadly speaking this looks a plausible outlook...

[frostyjoe]

It does indeed look like the Uk is going to return to Winter next week....Gfs has painted this picture for a few days now and it makes a change for it to put out a stable forecast considering the synoptics ,Ecm on the other hand is behaving very poorly and really should be binned! Note too ,that the Met Office have a similar synoptic evolution regarding Tuesday as the very cold uppers tuck tightly on the Northwestern side of the low pressure ,with a rain to snow scenario. As ever with these synoptics things will change, but broadly speaking this looks a plausible outlook...

oh that looks really cold for this time of year anyway is it going to only last to wednesday!?!

[Lightningboy]

yea i can see why they are not on now.. this is only going to be a sleety spell of wet snow and temps around 4c with no frost due to cloud and it will be back to 9c on wednesday.....

Not necearily dont know you spell that, but it could be like a April 2008 event maybe i hope.

Cheer up

Charts look interesting though

[Cheese Rice]

oh that looks really cold for this time of year anyway is it going to only last to wednesday!?!

The GFS has the cold (?) weather lasting into FI until the 7th of April, obviously this will change but hopefully will last for a while. The cold will definitely be over the UK by Wednesday and probably till at least (next) weekend.

Do you look at the charts? Here is the link to the GFS http://www.netweather.tv/index.cgi?action=nwdc;sess=

Edited March 26, 2010 by 10123

[frostyjoe]

The GFS has the cold (?) weather lasting into FI until the 7th of April, obviously this will change but hopefully will last for a while. The cold will definitely be over the UK by Wednesday and probably till at least (next) weekend.

Do you look at the charts? Here is the link to the GFS http://www.netweathe...ction=nwdc;sess=

yep i did thanks.. its just the bbc forecast has 9c for wednesday and surely if it was under this cold it wouldnt be 9c even for glasgow! http://news.bbc.co.uk/weather/forecast/2190