Model Output Discussion:

[kold weather]

The broad evolution now looks IMO pretty nailed out to at least 96hrs, the very interesting period between 96-144hrs could yet change somewhat and moderate away from the very snowy set-up progged but this does look interesting.

Somewhat reminds me of the December cold spell between say the 16-23rd of December, and we got a decent event out of that one!

[Thundery wintry showers]

Those areas that were very cold have warmed up substantially since then

True, but warmer seas would also translate to more convection. The setup shown by UKMO and GFS is as stonewall a "sunshine and snow showers" easterly type as they come (indeed it bears a fair resemblance to the 5-8 January 2010 one, and also to some extent 17th/18th December). I am refusing to believe in it fully until it comes within T+72 however due to the volatile nature of recent model outputs.

I think some excitement is understandable but we have to use some caution as it is still far away enough to change, and change quite substantially. For instance there still hasn't been complete GEFS ensemble agreement with some of the ensembles going for a milder outlook and the cold air never reaching us.

Correspondingly I don't think the evolution is quite nailed on to T+96- I think more like T+60 with the high pressure encroaching! If we reach the UKMO/GFS at T+96 there's only one way that setup will go.

Edited February 4, 2010 by Thundery wintry showers

[nick sussex]

Are we allowed to start getting excited yet?

No not yet! because we have a shortwave involved, this is what helps advect the cold air sw'wards. We're very close now but need to see the runs tomorrow to be sure, I'm probably being over cautious, so feel free to get semi-excited!

[Cecil Hogmanay Melchett]

If this chart comes off, I may see the most snowfall ever in my lifetime!

http://www.wzkarten.de/pics/Rtavn1441.html

http://www.wzkarten.de/pics/Rtavn1442.html

UKMO T+120 is increasingly cold and snowy too:

:)

Great news Paul surely you dont mean the most snow you have EVER seen?

I'm sooo excited mate i hope this comes off.

[kold weather]

The rest of the run is pretty insane as well its got to be said, set-up between 240-264hrs is almost an exact replica to how the 5-6th Jan snow spell evolved, of course that was rather an exceptional event so doubt it'd quite end up like that!

Still the whole run is quite frankly pretty immense!

I still can't believe a cold spell is on its way when I've got no laptop, unreal!

[Cecil Hogmanay Melchett]

Are we allowed to start getting excited yet?

Are you kidding i nearly fell off my chair when i saw ukmo,some places could get plastered if that comes off.

I can hardly containmyself and a last minute let down will have me heading for the bottle.

:)

[Snowplough33]

Both UKMO and GFS look very snowy, esp for the NE/East coast of England, and I['d be willing to bet any money there'd be a couple of troughs/fronts coming in to give more widespread snowfall for areas that don't have the easterly flow, for example the flow isn't that great for the SE but I'm pretty certain disturbances would help out here...

Places on the east coast would probably get some very big falls, very showery flow I'd imagine and not nearly as much moderation of the flow so coastal areas could do better then in recent years if that comes off.

From these charts, the east coast of Scotland will take its fair share too.

[Eugene]

Yes fantastic output, GFS 12Z FI is a snowfest

I wonder if conor has put his faulty crystal ball up for sale on ebay

[cooling climate]

T156 and there is 510 thicknesses into east Anglia and the southeast plenty of instability

i would have thought.

Further into the run t216 and it looks like the run is following the ECM 0z run. Massive

blocking over the Arctic the cold on this run looks to go on and on.

Absolute corker of a run. I would gladly take this to the bank. This run makes the last two

freeze ups look like the starters and now we are seeing the main course.

Edited February 4, 2010 by cooling climate

[karyo]

Brilliant 12z output so far! I really like the strong flow from the east/northeast and with the low pressure close by, I expect the snow showers to cross the country!

Karyo

[johnholmes]

Thank you very much UKMO 12z! I'll bank that run now please!

T+144: http://www.meteociel...44-21.GIF?04-17

I hope you are not starting a ramp Mr B?

[Southender]

OMG, this 12z GFS run is insane. It just does not warm up from start to finish.

EDIT: Atlantic breaks through on 20th Feb with a snowstorm, even then it looks like another reload from the North straight after!!!!

Edited February 4, 2010 by LeighShrimper

[Cecil Hogmanay Melchett]

Brilliant 12z output so far! I really like the strong flow from the east/northeast and with the low pressure close by, I expect the snow showers to cross the country!

Karyo

Mate i'll see you in the North west thread in a few days!!

[BLAST FROM THE PAST]

Yes get excited, I was excited back towards Mid Jan!..GFS, ECM, UKMO....ALL are on board with the CORRECT evolution. The UKMO is also probably as good a run as you could get...I suppose only downhill then?????

BFTP

[Thundery wintry showers]

Yes, I would happily "bank" either of those two runs- I'm still a long way away from having my "fill" of those sunshine and snow showers setups with vigorous convection over the North Sea. Both give an almost identical outcome in the T+96-144 range as it happens, so very strong operational agreement between the two.

Confidence will, however, become clearer once we see the GEFS ensembles, the ECM and the ECM ensembles. This morning's ECM went for a more watered-down slacker version but even the ECM 00Z setup, I imagine, would bring some snow showers to eastern districts, albeit not heading very far inland.

[karyo]

Mate i'll see you in the North west thread in a few days!!

It's a date!

It's been an unbelievable winter and the fun goes on!

Karyo

[Yeti]

Wow and if I thought the 120hrs was a good un, the 144hrs is quite unreal, thicknesses a good bit below 510 in the SE, would be a very snowy evolution for a good part of the country I'm pretty sure!

Indeed - and with the sun that bit stronger, and the North Sea that bit colder than the last cold spell, these charts would produce some very impressive convection. On the GFS and UKMO 12z the high is also in such a position that the whole of the eastern side would be affected.

I remember last cold spell people were complaining about the precip charts being too dry and that it was going to be a cold dry spell. When it came to it that was far from the case - but look at this already:

http://www.wetterzentrale.de/pics/Rtavn1504.png

For the GFS to pick up on that convection so far out, it's difficult to imagine how awesome the activity would be if that 144 chart actually verified!

Still a long way to go though yet, but things trending in the right direction. And obviously, those precip charts are only useful as an indication of the sort of pattern we're looking at atm, i.e. sunshine and snow showers.

[Matty M]

The UKM is amazing

Wait until its wetterzentralised.

Please no downgrades!

The approach of the cold air is but a mere 4 days away!

[PB22]

I hope you are not starting a ramp Mr B?

Not yet Mr H! Although I must admit this is looking a very interesting set-up potentially.

[pinball wizard]

If this chart comes off, I may see the most snowfall ever in my lifetime!

http://www.wzkarten.de/pics/Rtavn1441.html

http://www.wzkarten.de/pics/Rtavn1442.html

UKMO T+120 is increasingly cold and snowy too:

In the second link it looks as if there is a pocket of warmer air covering Eastern England from The Borders down to North Kent, I cant see what the 850's are for this area, anyone able to let me know?

[Lewis]

Don't want to be a downbeat member, i'm far from it.

I just want to see what the ECM has to say, i have an iffy feeling that the colder air is going to sink south, also notice that we are now relying on a short wave to import the colder air, so nothing nailed yet. It's going to get colder for sure, just a lot of uncertainty with regards the shortwave.

[Thundery wintry showers]

I'd like to preach a bit of caution here. It's easy to think that all of this is going to verify, since we've had some similar outputs come to approximate fruition earlier in the season, but I've seen similar setups to this go pear shaped at around T+96 before. I think it now looks very unlikely that we won't see some kind of cold spell in the coming week, but how cold and, more especially, how snowy is still subject to change.

If we're still seeing similar outputs to this tomorrow evening, cross-operational agreement and good ensemble agreement, then I will consider it close to being nailed on for a renewed spell of cold bright snowy weather. But today, the models are only just latching onto the pattern and I can't help but feel some of the excitement is premature.

[Geordiesnow]

Still got the ECM to come yet and this may still prove to be a downer especially if the high sinks above us quicker than expected but at least 2 of the main 3 models are going for a stronger easterly flow and the last 2(I did not see the 00Z GFS run so i don't if this showed a fairly strong easterly flow or not) GFS runs have shown the easterly to be quite potent and longer lasting.

Still all to play though and if by the weekend, we still see more or less the same charts then we can start talk about snowfall amounts.

Edited February 4, 2010 by Geordiesnow

[Cecil Hogmanay Melchett]

Don't want to be a downbeat member, i'm far from it.

I just want to see what the ECM has to say, i have an iffy feeling that the colder air is going to sink south, also notice that we are now relying on a short wave to import the colder air, so nothing nailed yet. It's going to get colder for sure, just a lot of uncertainty with regards the shortwave.

Yes i agree but its getting closer mate and you are in a PRIME position to get buried looking at the charts

Lewis.The east coast could be absoltely pummelled!! Lets hope(pray even)that ecm doesnt implode the whole thing.

Edited February 4, 2010 by happy days

[Solar Cycles]

I'd like to preach a bit of caution here. It's easy to think that all of this is going to verify, since we've had some similar outputs come to approximate fruition earlier in the season, but I've seen similar setups to this go pear shaped at around T+96 before. I think it now looks very unlikely that we won't see some kind of cold spell in the coming week, but how cold and, more especially, how snowy is still subject to change.

If we're still seeing similar outputs to this tomorrow evening, cross-operational agreement and good ensemble agreement, then I will consider it close to being nailed on for a renewed spell of cold bright snowy weather. But today, the models are only just latching onto the pattern and I can't help but feel some of the excitement is premature.

My sentiments too TWS. With the way the models have been performing as of late, I won't be getting to carried away just yet! Fantastic looking charts all the same! Edited February 4, 2010 by Solar Cycles