General Model Output Discussion

[TEITS]

Its not inaccurate, its just it isnt showing the temperature at 6pm. It is showing the maximum temperature for the three hours to 6pm. 'Bis zum termin' means 'to date' in German, hence it could be 4C at 3pm and 1C at 6pm and the GFS would be correct as the max temp during that period would be 4C.

I see what you mean now. However just checked the temps between 3pm to 6pm and it was still wrong by 2-3C.

[phil nw.]

If anything the front on the +48hr fax chart is further S from my region. Although for SW its slightly further N.

http://www.meteociel.../fax/fax48s.gif

I cannot really see much difference except the alignment of the front.

Thanks for answering that Dave,i lost my connection as i was typing a reply to Snowforme.

Yes the front stalls around the midlands and starts to pivot.

It`s all down to the old radar now i reckon and updated met warnings.

Edited December 28, 2009 by phil n.warks.

[❄️❄️❄️❄️❄️❄️❄️❄️❄️]

Hi could you give me a link to that i can never fint it in the meteociel site!! Thanks

http://www.meteociel.fr/modeles/archives/archives.php

[andy_leics22]

I tell you what mate i've given up looking at the models for tomorrow and this even includes the BBC forecasts.

For example on pg 402 the forecast for E Midlands tomorrow is persistant snow moving in later and yet if you look at 403 it differs. On pg 401 it just says rain, sleet, snow. The last BBC forecast I watched suggests heavy snow for N England on Wed and I can't see much evidence of this on the fax charts.

I can assure everyone that even at this late stage changes will occur and this includes the models/forecasts. If I was honest this is the most complicated situation I have ever known since following the models. A real blast to the past with these synoptics.

TEITS take a look at the UKMO 12z model... Bags of PPN over West and East Midlands tomorrow night, temps forecasted to be around 0c at the time aswell :lol:

[Derp Patrol]

I used to hate winters for the boring cold/mild days with rain and no chance of snow here, but this is ridiculous and has changed my stance completely! Not a sight of a breakdown in almost all models, and am I right that even down here near London I could be in for a good snowfall? because this February was great, but was fairly brief.

Hopefully this comes off, especially as I am due to have mock exams when I go back to school, I probably won't be able to leave the house looking at the current charts!

[yamkin]

let the hypoerbole begin

S

Not bad COAMPS 12Z 72h as well :lol:

[Cumulonimbus Tower]

Looks like the ECM is still keen on its previous idea of dropping a trough down into scandi/north sea around 168 bringing in a northwesterly and hopefully northeasterly later on :lol:

[I remember Atlantic 252]

this ecm reminds me a bit of 17-19 dec this year, but was pants for areas away from the SE

[casparjack]

I'm looking at this analysis chart and thinking that things might be slightly more advanced...

The temperature here has hovered around 0.5c all day and at around 3pm started to fall reaching 0.1c at about 5pm, it has now started to rise quite steadily and is now 0.5c and rising, upper air temps have risen too according to the NW 850s on the radar.

Light ENE wind and fairly steady pressure though, gut feeling is that it will start as rain here overnight...

Edited December 28, 2009 by casparjack

[Duane S.]

Incredible incredible charts on offer tonight and a lot is in the reliable time frame, whenever the heck that is!

Nice to see the GFS stop being so stubborn and finally join the party. Took its time though!

This setup is as good as it gets for me down 'ere. It is absolutely ooooooozing potential.

What is my biggest concern is the trough over Scandinavia. That, as opposed to that SW off Norway, does have the power to put the mockers on a sustained cold spell which we are edging ever closer to with these charts.

Edited December 28, 2009 by s4lancia

[yamkin]

What a ECM 12Z 96h chart

[cyclonic happiness]

The ECM is so cold looking so afr, it made me physically shiver to look at it!!

http://www.meteociel.fr/modeles/ecmwf.php

We would surely be in for a cold spell for the history books if this comes off!!! (mmm...where have I heard that before )

Seriously, it's looking really really good for the foreseeable.

[❄️❄️❄️❄️❄️❄️❄️❄️❄️]

I'm surprised there aren't more post on the 12z ECM, or has everyone past out looking at them?

[David-kig]

anyone know what ecm has done with this low if it got it further north or south?

[phil nw.]

The ECM is so cold looking so afr, it made me physically shiver to look at it!!

http://www.meteociel...deles/ecmwf.php

We would surely be in for a cold spell for the history books if this comes off!!! (mmm...where have I heard that before )

Seriously, it's looking really really good for the foreseeable.

Yes very cold output across all the 12z models.

Here at T120hrs.Sat.

http://www.wetterzen...s/Rtavn1201.png

http://www.wetterzen...cs/Recm1201.gif

http://www.wetterzen...cs/Rukm1201.gif

http://www.meteociel...&ech=120&mode=0

After the midweek Low has finally eased away SE we are left in a very cold Polar Continental flow from the North East.

A very solid cold pattern with a Upper High to our North West,Troughing coming South over Scandinavia and a Southerly tracking jet and low pressure over the nearby continent.

These are excellent sypnotics for a prolonged cold spell with hard frosts,and chances of further snowfalls for many areas.

Edited December 28, 2009 by phil n.warks.

[TEITS]

General trend becoming clearer now.

Once the LP clears we see a shortlived ENE,ly. However this isn't going to be a classic E,ly with heavy snow showers in E areas. What happens beyond this is it remains fairly dry and very cold with the exception of Scotland who might see more prolonged snow due to the SW.

Beyond this and the flow changes towards to a slack N/NW,ly but remaining mainly dry and very cold. After this we see a LP system tracking S but to be honest im going way too far ahead.

At the moment if your after snowfall then it looks as though your best chance is via this LP. Otherwise I cannot see much potential for snowfall with the exception of E Scotland. However in saying this surprise snowfall often comes along and im not 100% the models have +168 to +240 correct yet.

[bluearmy]

interestingly enough, ecm 12z does bring the low up to the sw tip of ireland wed am before elongating the trough along the north french coast. so GFS playing around with the low in the sw approaches towards ireland wasnt so far away. however, ecm doesnt bring the 0c isotherm north of the M4 corridor, though the precip gets right up to cumbria se to the humber.

i note that once the occlusion has fizzled out central and sw england, there is only precip shown for kent and sussex from the noreaster. we'll hope for some disturbances in the flow i think. ne england, eastern and northern scotland look to get a fair amount of convective snowfall.

[ronant]

General trend becoming clearer now.

Once the LP clears we see a shortlived ENE,ly. However this isn't going to be a classic E,ly with heavy snow showers in E areas. What happens beyond this is it remains fairly dry and very cold with the exception of Scotland who might see more prolonged snow due to the SW.

Beyond this and the flow changes towards to a slack N/NW,ly but remaining mainly dry and very cold. After this we see a LP system tracking S but to be honest im going way too far ahead.

At the moment if your after snowfall then it looks as though your best chance is via this LP. Otherwise I cannot see much potential for snowfall with the exception of E Scotland. However in saying this surprise snowfall often comes along and im not 100% the models have +168 to +240 correct yet.

Hmm looks to me like there will be some very significant snowfall for the south as the frontal zone sinks southwards. Reckon this will effect southern central areas, the south east. With a strong wind conditions could be very very nasty. After that its just FI really IMO.

But starting tomorrow we have three very disruptive days of snow effecting very large parts of England and Wales.

Edited December 28, 2009 by ronant

[NorthantsSnow]

Where can I view the early ECM output please? (i.e. up to 72hrs)

I want to see what it does with that 0c isotherm.

[Lewis]

I think it's safe to say with the 12z gfs, all models including the euros have come to some kind of agreement in the reliable time frame. I agree with TEITS regarding it being a very cold and mainly dry run later in FI, but still looks fantastic for a prolonged cold spell.

At least we have the short term some what nailed on by all models, and i'm sure later on down the line they will be upgrades to precipitation.

We got there in the end :unsure:

Interesting 18z ahead.

Lewis

Where can I view the early ECM output please? (i.e. up to 72hrs)

I want to see what it does with that 0c isotherm.

http://www.meteociel.fr/modeles/ecmwf.php?ech=72&mode=1&map=0

Edited December 28, 2009 by Storm Force Lewis

[TEITS]

Hmm looks to me like there will be some very significant snowfall for the south as the frontal zone sinks southwards. Reckon this will effect southern central areas, the south east. With a strong wind conditions could be very very nasty. After that its just FI really IMO.

Always possible that once the front sinks S this brings prolonged snowfall for the S. However at this stage its impossible to tell what precip will be left on the front. My post was referring to what happens afterwards.

[Solar Cycles]

General trend becoming clearer now.

Once the LP clears we see a shortlived ENE,ly. However this isn't going to be a classic E,ly with heavy snow showers in E areas. What happens beyond this is it remains fairly dry and very cold with the exception of Scotland who might see more prolonged snow due to the SW.

Beyond this and the flow changes towards to a slack N/NW,ly but remaining mainly dry and very cold. After this we see a LP system tracking S but to be honest im going way too far ahead.

At the moment if your after snowfall then it looks as though your best chance is via this LP. Otherwise I cannot see much potential for snowfall with the exception of E Scotland. However in saying this surprise snowfall often comes along and im not 100% the models have +168 to +240 correct yet.

That's exactly how I see it Tetis, very cold but little in the way of snow for the majority. Apart from the low temps, not much to get excited about really!

[kent]

General trend becoming clearer now.

Once the LP clears we see a shortlived ENE,ly. However this isn't going to be a classic E,ly with heavy snow showers in E areas. What happens beyond this is it remains fairly dry and very cold with the exception of Scotland who might see more prolonged snow due to the SW.

Beyond this and the flow changes towards to a slack N/NW,ly but remaining mainly dry and very cold. After this we see a LP system tracking S but to be honest im going way too far ahead.

At the moment if your after snowfall then it looks as though your best chance is via this LP. Otherwise I cannot see much potential for snowfall with the exception of E Scotland. However in saying this surprise snowfall often comes along and im not 100% the models have +168 to +240 correct yet.

At last an honest assumption, never expected any snow living on the south coast in Poole, and doubt to see any in the near future, 1cm in the last ten years has led to utter contempt of promising model outputs anyway good luck to those who do.

[rmc1987]

I used to hate winters for the boring cold/mild days with rain and no chance of snow here, but this is ridiculous and has changed my stance completely! Not a sight of a breakdown in almost all models, and am I right that even down here near London I could be in for a good snowfall? because this February was great, but was fairly brief.

Hopefully this comes off, especially as I am due to have mock exams when I go back to school, I probably won't be able to leave the house looking at the current charts!

Mmmm I don't think it'll get that bad. You'll still be able to leave the house and sit your exams! I suspect we will be let down by this more than other parts in terms of snowfall amounts. It'll break down at some point so best to make the most of the cold. I'll be grateful for any snow we might get too. Good luck with those exmas too ;-)

EDIT - A lot of this snowfall sounds very hyped up indeed!

Edited December 28, 2009 by rmc1987

[Michael Fishermans Friend]

I was thinking this too - not alot of snowfall about after this LP episode is out of the way, I'm not sure if eastern areas will recieve any convectional stuff from Friday onwards in the north easterly air stream? - there after looking pretty dry and as said cold, this is backed up by Weatheronlines GFS ppn model. ECM to me looks no where near as good as yesterdays 12z and later on in the run looks a bit 'shaky' - but thats a long long way off. :unsure: