Model Output Discussion

[MP-R]

Yep even now the track of Monday's system still not really agreed

Thank heavens, I've almost lost hope completely down here. Fortunately, the first real northerly low seems to be on Friday:

Monday:

http://www.wetterzentrale.de/pics/Rtavn241.html

Wednesday:

http://www.wetterzentrale.de/pics/Rtavn721.html

Friday:

http://www.wetterzentrale.de/pics/Rtavn1201.html

I'm just hoping these Channel Lows live up to their expectations of being full of last-minute changes as we are so close down here but look like getting sleet at best. Especially after the disaster of lack of snow last night despite forecasts, it just shows how marginal things are getting here in the south.

[TEITS]

Much better 06Z.

This not only agrees with the NAE but the LP becomes seperate. This could be interesting for the rest of the run because the colder air to the N will push further S.

http://www.wetterzentrale.de/pics/Rtavn482.png

[Eugene]

Yes a better 06Z, GFS 00Z was out on it's own in regards the northern extent of mild air so this is nearer to the rest, could be an ice day somewhere under all that heavy snow

http://www.wetterzen...s/Rtavn3617.png

Worth pointing out GFS 00Z for friday was the warmest model run, most other runs bring another risk of snowfall for the midlands northwards on friday, i wonder if GFS 06Z will bring this risk too, lets wait and see.

Edited February 21, 2010 by Eugene

[kold weather]

Wednesday's front looks further north on this run and a at a different angle as well, however it has to be said the angle is soemwhat better for snow and temps aren't even marginal on the northern part of the system at all.

So a very interesting 5-7 days coming up now, I'm happy to see my call of attack from the SW by LP's and snow threats has come off.

[andymusic]

Yep even now the track of Monday's system still not really agreed, however the GFS 0z run is the northerly most run whilst the NAE appears to have broad agreement from most of the other

models so I'd side with that option.

Tuesday and Wednesday looks good for the Midlands before any threat probably moves northwards unless the models ar being over zealous with this one, could well get some big falls up in Northern England and S.Scotland as well given the pattern will become quite static..unless the ECM is correct!

EDIT---06z now also agrees with the NAE.

BBC NEWS 24 is going for that too in their latest forecasts - currently going against the warning advisories that the meto have out - especially for wales - I'm expecting an update to the metos warnings for tomorrow for wales - meto do advise the beeb after all

snow front over wales will go further north into mid wales - meto will need to include other counties in wales on their advisory to come into line with bbc news24

Edited February 21, 2010 by andymusic

[Blizzard_of_Oz]

Great 00z with lot's of snow around next week. Over a foot of snow here for me at the moment and still like a blizzard outside on the staffs Cheshire border.

They were all doubting you last week Robert, your scientific method does work then.

[swfc]

They were all doubting you last week Robert, your scientific method does work then.

i did make fun of the guy but he looks spot on.good call robert.

[Rollo]

Wednesday's front looks further north on this run and a at a different angle as well, however it has to be said the angle is soemwhat better for snow and temps aren't even marginal on the northern part of the system at all.

So a very interesting 5-7 days coming up now, I'm happy to see my call of attack from the SW by LP's and snow threats has come off.

Yes indeed KW a good call-it certainly looks as february will go out with widespread snow over many areas.

[kev238]

The latest NAE goes for a south east correction of precipitation- subsequently the snow zone- whilst largely in the same area- has much lower precipitation totals and accumulations.

[kold weather]

06z indeed shunts the risk further north then the 0z run for Wednesday onwards, but thats because it develops a rather unlikely low pressure system over N.Ireland. Whilst the past GFS runs have toyd with the idea none are nearly as far north-west as that run suggests.

However this does need to be watched because if that happens whoever is on the northern side of that low could get big falls. The 06z GFS for example gives a rather special fall to W.Scotland on this run with some big amounts.

Still the low evolution IMO is a little off on this run.

[Eugene]

Better run for friday on 00Z temps were around 8C in the midlands at midday on 06Z now 1C at midday still would be cold rain though for the midlands as dewpoints arent cold enough BUT the risk is there for snow, just need slightly colder air and dewpoints, the models for tomorrow were leaning towards rain 5 days ago so it could easily be upgraded like tomorrow was

[andymusic]

The latest NAE goes for a south east correction of precipitation- subsequently the snow zone- whilst largely in the same area- has much lower precipitation totals and accumulations.

the nae completely messed up saturday morning here in wales and the GFS was right with no snow showers - tomorrow will be nowcasting/radar to see how far north the front gets

I don't think i can trust any of them at the moment - they are all undecided on exact details

Edited February 21, 2010 by andymusic

[kold weather]

The latest NAE goes for a south east correction of precipitation- subsequently the snow zone- whilst largely in the same area- has much lower precipitation totals and accumulations.

You couldn't make it up, thje GFS finally agrees with the NAE only for that model to shunt it further south-east again, as you say the snowfall is now very light on the 06z NAE, whilst the SE get some big totals, probably would need warnings just for the rain based on that run!

However I think the NAE has now shifted too far the other way, the 0z run IMO is spot on the money...

[kev238]

Yeah you are correct- it will be radar watching but just pointing out what it shows. I live in Nottingham so this isnt a IMBY comment- just what it shows and to be fair to the NAE I would say it is a great tool for predicting snow/ rain. Not so good for little disturbances but very good for larger systems. It was excellent for Thursday and was great for many other events as well.

The BBC will change their forecast to reflect this update as they use this for their forecasts.

[TEITS]

the nae completely messed up saturday morning here in wales and the GFS was right with no snow showers - tomorrow will be nowcasting/radar to see how far north the front gets

I explained this yesterday but you must of missed my post.

The NAE was only predicting light wintry showers and thats exactly what occured. Such is the nature of showers no model will ever accurately predict these and I bet the same will be the case in 50yrs time. Like I said yesterday you need to properly look at the model output rather than being misled by the pinks.

Im sorry to say this but far too many members pay too much attention to the pink blobs on the NAE and the white blobs on the BBC forecasts!

Back to the models and my fear about tomorrow looks like being right. The NAE has shifted the LP further S meaning the precip will be further S!

http://expert.weatheronline.co.uk/daten/proficharts/en/nae/2010/02/21/basis06/ukuk/prty/10022218_2106.gif

[swfc]

the nae completely messed up saturday morning here in wales and the GFS was right with no snow showers - tomorrow will be nowcasting/radar to see how far north the front gets

I don't think i can trust any of them at the moment - they are all undecided on exact details

Good points there.pity the low over iceland does not move south east .would be a great run

[Interitus]

Much better 06Z.

This not only agrees with the NAE but the LP becomes seperate. This could be interesting for the rest of the run because the colder air to the N will push further S.

http://www.wetterzentrale.de/pics/Rtavn482.png

However in advance of this it brings slightly higher temperatures as witnessed in the 850s

[kev238]

Even if the first low pressure slides South, there are more opportunities in the week for snowfall, though sliding South could be the trend for the week!

[swfc]

170 hrs,pressure rise over scan.wheres that going.???

[Blizzard_of_Oz]

I explained this yesterday but you must of missed my post.

The NAE was only predicting light wintry showers and thats exactly what occured. Such is the nature of showers no model will ever accurately predict these and I bet the same will be the case in 50yrs time. Like I said yesterday you need to properly look at the model output rather than being misled by the pinks.

Im sorry to say this but far too many members pay too much attention to the pink blobs on the NAE and the white blobs on the BBC forecasts!

Back to the models and my fear about tomorrow looks like being right. The NAE has shifted the LP further S meaning the precip will be further S!

http://expert.weathe...022218_2106.gif

I have read all of your posts TEITS and indded you did predict this but didnt you post a chart saying any 1 to the NW of that would get snow or am I wrong could you explain what areas might expect snow now thankyou?

[kold weather]

Back to the models and my fear about tomorrow looks like being right. The NAE has shifted the LP further S meaning the precip will be further S!

http://expert.weathe...022218_2106.gif

Yeah tohugh I think the 06z NAE has gone too far south actually, I see no reason to doubt the GFS 06z run given all other models including the NAE's 0z run agreed with it. I know it may have picked up a trend BUT I think the likely evolution will be somewhat further north then the NAE suggests....

It was ironically too far south by a LONG way until 24hrs ago with todays evolution and I think the same will happen with tomorrows low.

Edited February 21, 2010 by kold weather

[nick sussex]

I explained this yesterday but you must of missed my post.

The NAE was only predicting light wintry showers and thats exactly what occured. Such is the nature of showers no model will ever accurately predict these and I bet the same will be the case in 50yrs time. Like I said yesterday you need to properly look at the model output rather than being misled by the pinks.

Im sorry to say this but far too many members pay too much attention to the pink blobs on the NAE and the white blobs on the BBC forecasts!

Back to the models and my fear about tomorrow looks like being right. The NAE has shifted the LP further S meaning the precip will be further S!

http://expert.weatheronline.co.uk/daten/proficharts/en/nae/2010/02/21/basis06/ukuk/prty/10022218_2106.gif

I agree the NAE can be misleading with showers and is better with frontal precip scenarios. As for tomorrow I don't think we've seen the last of the changes. Of much more interest IMO is the ECM 120hrs, if people are looking for a very good snow event that really is the pick of the bunch however given the volatile nature of the output the odds on that verifying are low.

[Tim Bland]

Back to the models and my fear about tomorrow looks like being right. The NAE has shifted the LP further S meaning the precip will be further S!

http://expert.weatheronline.co.uk/daten/proficharts/en/nae/2010/02/21/basis06/ukuk/prty/10022218_2106.gif

Edited February 21, 2010 by Tim Bland

[TEITS]

The white blobs on the bbc forecasts and the forecaster mention wales two or three times in the same sentence as the word snow - aswell as the words "well into wales"

My point is if you had checked yesterdays precip totals you would of noted 0mm which means nothing significant. At no stage did any models/forecasts suggest anything of significance yesterday.

As an example tomorrow the NAE still shows pinks across my region but if you look closely much of the precip will be further S than my region.

[andymusic]

My point is if you had checked yesterdays precip totals you would of noted 0mm which means nothing significant. At no stage did any models/forecasts suggest anything of significance yesterday.

As an example tomorrow the NAE still shows pinks across my region but if you look closely much of the precip will be further S than my region.

news 24 10.30am forecast - 10cms snow south and mid wales from 4-5am to about middle of tomorrow afternoon - no change there - regardless of nae etc etc

includes the midlands also

Edited February 21, 2010 by andymusic