Winter Model Discussion - Cold Hunting -12Z 06/01/13

[124alex]

Ill take this please

[Anti-Mild]

I think what many members are forgetting, and I include myself in this (until I thought about it this morning), is that the effects of the SSW which has only just occurred will not be felt until the middle of next week, and that the evolution to colder conditions this weekend are, to some degree, a bit of a bonus before the main event (hopefully).

Up to +120 and it's broadly similar to the 6z, slightly lower heights over Scandi and E. Europe.

[Cheshire Freeze]

I actually think this is going to be a better run. The trough is dropping down bits of energy from the NW and all these are doing are travelling SE whilst the HP in the Atlantic tries to ridge in behind.

[Geordiesnow]

Can't really see much cold sustained occuring with those low heights and shortwaves to the South of Greenland, I really can't. May see some half hearted attempts as the runs are suggesting at this moment in time.

Really do need to knock out the PV for six like the ECM has hinted at if people want something more sustained and convincing.

[Stu_London]

still pretty good consistency with the 06z up to +132 which shows how much better a handle the GFS has grapsed in the last 24-48 hours

[UV-RAY]

Low appears to be undercutting could be rain to snow event especially for the East and SE.

[tight isobar]

Gfs,12x, fab for large scale snow event....again fully expect reinforce,on 18z..:-)

[Timmytour]

i think I see where this run is taking us...

[Stu_London]

Can't really see much cold sustained occuring with those low heights and shortwaves to the South of Greenland, I really can't. May see some half hearted attempts as the runs are suggesting at this moment in time.

Really do need to knock out the PV for six like the ECM has hinted at if people want something more sustained and convincing.

The SWs were there on the -6z and that had a pretty solid cold spell.

Agree that this 'event' wont be that severe however.

Slightly better cold pooling to the east however - which should take some of the marginality out of the event for the weekend if verifying.

Edited January 7, 2013 by Stu_London

[winterof79]

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=138&mode=1

http://modeles.meteociel.fr/modeles/gfs/runs/2013010712/gfs-2-132.png?12 Thats ok to me and not going to look further at present.

[Troubleatmill]

indeed, but all the op models go to the top of the strat now. ensembles less clear ???

no it doesnt.

small changes make bigger differences later. they may work out for us but in the short term this is worse than the 06z for cold

EDIT: although the orientation of the high is better for advecting the lower uppers so we'll see

Without a doubt not questioning that all do, but i cant see any info about the ECMWF (i take it it does) as only the GFS has open to public all data? i wish i knew why this was, UKMET and ECM and GEM should all follow suite. Freedom of information act lol!!

[fergieweather]

Just wanted to stress an important (indeed critical, for this thread) bit of guidance from our medium range folk at Exeter: Do NOT confuse current outlook for a return to the cooler conditions next few days with SSW effect. The latter has NOT yet shown it's hand in any NWP output in any reliable sense. They continue to expect this next key phase - with hugely uncertain outcome - to become a feature appearing from around 10d onwards, and NOT in the more near-term medium range. Current set-up into weekend / early next week etc is not related to SSW in their estimation - just bob-standard winter fare.

[trisnow]

To my completely untrained and novice eye does the jetstream forecast look better for us around next weekend? Is that the best way for a novice to see if the Atlantic is being held at bay? Thanks.

[The Beast From The East]

Thanks Ian F, that's the news I was hoping to hear.. Treat this weekend as a bonus then

[TAFKAP]

i think I see where this run is taking us...

[Weathizard]

Hmmmmmm interesting delopments at 156, looks like the icelandic shortwave is moving SE and the high is trying to ridge north. Looks as though the high won't make it but it possible...

[Stu_London]

Just wanted to stress an important (indeed critical, for this thread) bit of guidance from our medium range folk at Exeter: Do NOT confuse current outlook for a return to the cooler conditions next few days with SSW effect. The latter has NOT yet shown it's hand in any NWP output in any reliable sense. They continue to expect this next key phase - with hugely uncertain outcome - to become a feature appearing from around 10d onwards, and NOT in the more near-term medium range. Current set-up into weekend / early next week etc is not related to SSW in their estimation - just bob-standard winter fare.

thank you Ian - surely some of modelling where we are seeing signs of fracturing of the tropospherical vortex are SSW related?

If so, then this would surely impact on the current cold spell progged and how and if it breaks down

[Methuselah]

Ski Sunday? http://nwstatic.co.uk/viewimage.pbx?type=gfs;date=20130107;time=12;ext=159;file=h850t850eu;sess=9b7c739dc0fa5356393baec33af0b7a7;

[MR EXTREMES]

It's out to T96..

Low to our West is slightly stronger

i do apoligise i was looking at the gefs sorry.

well cold spell looks on but the alantic looks blocked but so far no ridge into greenland is it possible the azores or alantic heights shifting west right over us i hope not.

[Cecil Hogmanay Melchett]

Think i have seen enough to call this a very very brief flirt from the east,that energy to the NW is going to do for us again IMO.

[MR EXTREMES]

guess what its a sinker no blocking into greenland with low heights going over the top of the scandi ridge looks like a sinker but not a 24hr cold snap with surface temps cold.

still looks odd compaired to the 6z 18z

Edited January 7, 2013 by model rollercoaster

[Stu_London]

Toppler alert at +162.

Could topple and then retrogress in FI - that would be my bet.

[Geordiesnow]

The SWs were there on the -6z and that had a pretty solid cold spell.

Agree that this 'event' wont be that severe however.

Slightly better cold pooling to the east however - which should take some of the marginality out of the event for the weekend if verifying.

Problem is Stu, that is all FI and very speculative as per usual, especially when it comes to a cold set up.

I don't think it would take much to get a slightly stronger easterly flow but at this stage, you have to say any easterly flow won't be too strong and its not going to last all that long, or the way our luck has been going so far we just remain in a more southerly south-easterly flow.

Interesting outputs but as far as snowfall is concern, don't see too much of that atm.

[Anti-Mild]

I think what many members are forgetting, and I include myself in this (until I thought about it this morning), is that the effects of the SSW which has only just occurred will not be felt until the middle of next week, and that the evolution to colder conditions this weekend are, to some degree, a bit of a bonus before the main event (hopefully).

Up to +120 and it's broadly similar to the 6z, slightly lower heights over Scandi and E. Europe.

Just wanted to stress an important (indeed critical, for this thread) bit of guidance from our medium range folk at Exeter: Do NOT confuse current outlook for a return to the cooler conditions next few days with SSW effect. The latter has NOT yet shown it's hand in any NWP output in any reliable sense. They continue to expect this next key phase - with hugely uncertain outcome - to become a feature appearing from around 10d onwards, and NOT in the more near-term medium range. Current set-up into weekend / early next week etc is not related to SSW in their estimation - just bob-standard winter fare.

Check me out! Exeter, I'm available for employment - heck, i'll even make the tea!!

12z pretty messy after 144, FI still after 108 probably.

[Timmytour]

That low in the Med is deeper on this run....could yet prove interesting on future runs

Edited January 7, 2013 by Timmytour