Model Output Discussion - 8th - 14th January

[chionomaniac]

The block looks like hitting the shortwave south with azores amplification set to reinforce.

[kold weather]

A nice slidder from the GFS at 192hrs-240hrs, similar broad synoptics to the 00z ECM but different details.

ECM is better simply because there is more cold air to tap into then the GFS which has a fairly weak easterly, cold but not all that cold on the 06z.

[feb1991blizzard]

Well big changes in the output this morning as the models wrestle with the teleconnection changes, particularly from the ECM which has done a complete volte face.

I’m not sure that I agree with Steve M that a T264 or T268 ECM would be ‘epic’, as with the height anomaly where it is, we would only be in a battleground situation and there would be no floodgates from the East.

However, this is all a long way off, and I would remind newer members that when similar set-ups have been at this range in the past, prior to 2008, then failure (for cold) was nearly always the outcome.

Although we had some epic easterlies back in the 80s, even then the most common route to heavy snow was frontal incursion coming up against a continental feed. which gives moist air and those big thick flakes, thats one thing i have missed lately, particularly now i have moved somewhere that might benefit from such a setup, which the models this morning are suggesting. although of course will probably change again, anyway the ECM 0z is the run of the day for me, the PV is almost removed from our side of the hemisphere, and as long as that arctic high can stick around, we would have quite a spell of fun and games i would say, although all FI of course.

[Tim Bland]

Arctic high in place. PV pushed away NW. Lots of cold to the east. All we need is that trigger.

[Cecil Hogmanay Melchett]

Goodness me the mother of all battles going on here on ther 06zsensational developments this morning guys and we have a decent chance of the BEAST!! :lol:

[Weathizard]

What is good to see is we are seeing subtle upgrades every run, I'd much prefer that than one run of beastly proportions, gradual improvement.

[nick sussex]

I'd kick the lower resolution of the GFS output into the trash as this goes against where the main negative anomaly should be, this is supposed to transfer west and although you're likely to be left with some energy in Greenland you shouldn't be seeing that deep a PV that far east.

In the higher resolution output it arrives at the same place as the ECM and thats the main thing for now.

[ITSY]

just seen the 00Z and 06Z - upgrades all round from both major models this morning. lets keep this up for another few days then we can talk about an upcoming cold spell. for now the models have merely switched to cold as a possible outcome.

[shedhead]

What is good to see is we are seeing subtle upgrades every run, I'd much prefer that than one run of beastly proportions, gradual improvement.

Very much so, trend is everything in this game, chasing cold for the UK rarely follows a smooth linear curve.

In the meantime, here's something to whet the appetite......... http://www.itn.co.uk/world/36647/Alaskan+town+calls+in+National+Guard+to+help+clear+snow

Edited January 11, 2012 by shedhead

[Cecil Hogmanay Melchett]

I can live with 06z GFS its an improvement on the 00z runs all eyes on the meto update and the 06z ensembles.

Nice to be off work today even if we dont see cold this is the kind of stuff weather geeks love!!(like me).

[The Northern Ramper]

Although we had some epic easterlies back in the 80s, even then the most common route to heavy snow was frontal incursion coming up against a continental feed. which gives moist air and those big thick flakes, thats one thing i have missed lately, particularly now i have moved somewhere that might benefit from such a setup, which the models this morning are suggesting. although of course will probably change again, anyway the ECM 0z is the run of the day for me, the PV is almost removed from our side of the hemisphere, and as long as that arctic high can stick around, we would have quite a spell of fun and games i would say, although all FI of course.

Indeed

Some of our greatest falls in this area is when a battleground situation stalls over us and then the block remains too strong, this is certainly an option with this kind of set up.

Edited January 11, 2012 by Snow Guy

[Zakos]

What is good to see is we are seeing subtle upgrades every run, I'd much prefer that than one run of beastly proportions, gradual improvement.

yes, as i said earlier, the atlantic arival is continually being delayed and the jets strength reduced, every single run. I really think brian gaze has simply got this wrong, i think at least -5 air will reach at the very least eastern areas at some point in the next 14 days. Snow is a

[Frosty.]

There is a cold frosty weekend ahead and it's getting no mention, surely that is worth discussing as it will be a lot colder compared to the very mild weather we are having this week so far, colder and brighter weather spreading south across scotland tomorrow but 1 more mild day for southern england at 11c, then colder for fri, sat and sun with widespread frosts and some fog.

[cooling climate]

Lots of positives to be taken from the 06z run with better heights pushing in quicker into northwest Russia and across to Svalbard and even Greenland which end up producing a good block over

Scandinavia. I would expect to see some excellent ensembly members showing a strong easterly

(the beast). This evenings model outputs should be worth the wait.

[Tim Bland]

My only concern with these synoptics is that we stay under the ridge (High pressure) the atlantic stays to the west and the cold to the east. I pray the 2 meet in the middle or the atlantic undercuts at some point! I agree though that at least some frosts and seasonal weather will do for the time being.

Edited January 11, 2012 by Paul

[Andy_]

It seems that the models are back on form now, one thing i've noticed about the GFS is (and this could just be coincidence), but it has 'on' and 'off' days... yesterday was an 'off' day, the day before was an 'on' day, the day before that was an 'off' day, and the day before that was an 'on' day!

At long last we have the ECM back on board, but naturally this is one run... if the 12z has similarities then this will definitely be an 'on' day for both the GFS and ECM.

The ECM is not only brilliant at first glance, but would be sublime in the long term with all of this 'yellow' high pressure in the high arctic.

[swipe]

Well big changes in the output this morning as the models wrestle with the teleconnection changes, particularly from the ECM which has done a complete volte face.

I’m not sure that I agree with Steve M that a T264 or T268 ECM would be ‘epic’, as with the height anomaly where it is, we would only be in a battleground situation and there would be no floodgates from the East.

However, this is all a long way off, and I would remind newer members that when similar set-ups have been at this range in the past, prior to 2008, then failure (for cold) was nearly always the outcome.

As much as I enjoy your posts, Ian. Please could you increase your font size as I struggle to read your posts with my bad eyesight?

[SMU]

The ensembles are GOOD- but they are not there yet- but it is the 06z so we cant have to high expectations-

I would say TB 14 looked the best at 192- but there are some other very good ones in there-

PV lobe squashed over benelux is always a welcome site!

S

[swilliam]

Control run is having non of it

Shows that it is still finely balanced.

[OldMetMan]

Fascinating models today.

A mild/cold battle such as depicted by both the ECM and GFS we haven't seen in a while. Given the strength of the HP shown to develop, and the developing depth of cold over Russia, it would seem the cold would eventually win out.

Meanwhile, I still think the polar jet is shown as too strong and that most of the action will be to our SW rather than NW, but that remains to be seen. The crucial thing will be where the axis of the disrupting upper trough will be as this will determine the western extent of the initial cold air incursion, and thus any snowfall.

It will be very interesting to see whether the models show any sign of an extended cold spell by building HP towards Greenland.

[kold weather]

P7 gives a -18C easterly!!

Overall the ensembles are a mixed bag, some give a real potent easterly, whilst some keep a more westerly pattern, though even then it maybe cool zonality that is progged.

[Heisenberg]

This weekend is shaping up to be a nice cold affair. The NW forecast for my area is showing 1's and 2's for most of the day then going up to 5 for a short time. Much better than the 12's we have been getting.

[nick sussex]

Come on guys, discuss the shorter term as we are about to have the most widespread frosts of the winter so far, surely something to celebrate in such a mild winter thus far? sadly it gets shoved to one side because of something that might happen next week or later!

I don't think a few hard frosts are going to satisfy people Frosty , so whilst its nice to see that most people in here want to see some snow.

Just to explain why the GFS 06hrs lower resolution operational output is liable to be wrong, if you look at the thoughts of NOAA they expect the strongest negative height anomaly to be near British Columbia, this does not teleconnect with a strong negative height anomaly over Greenland.

Also they expect a warming in the plains with above average temps towards the ne of the USA, the PV over more western parts of Canada downstream correlates with this.

For this reason if they're right you'd expect more retrogression of the pattern over Europe, and we know what that means!

I don't want to ramp up things too much as we've seen the models all over the place during the last week, we'd need to see this better trend over several days and the key to have any chance of a quicker change to colder conditions is events within 168hrs.

[Frosty.]

We have a cold snap in front of our noses (this weekend) and nobody has mentioned it, apart from me, the possible much colder pattern is very much in the balance despite some positive output this morning but within the reliable timeframe we have some cold frosty nights and chilly days which are now set in stone and anything beyond that is still on very shaky ground.

At last, a few mentions of it

Edited January 11, 2012 by Frosty039

[Tom Montalbano]

Control run is having non of it

Shows that it is still finely balanced.

But getting there a bit further down the line.

http://176.31.229.228/modeles/gens/run/gens-0-1-312.png?6

Regards,

Tom