Winter Model Discussion 12Z 09/01/13> The hunt for cold ?

[mcweather]

some one posted the latest verification stats for days 5 and 6 this morning which showed the ukmo leading the ecm with the gfs way back in third so if the ecm comes in even half as good as yesterday I will be happy.

To be honest 144 is as far as any of us should be looking at the moment the ukmoat that stage has warm air being pumped up into the arctic all the way from Gib so chances of an arctic or scanidi high coming into play down the line which could be what GP was alluding to when he spoke of the second more aggressive cold attack around day 10 in this mornings model thread ( POST 677)

You beat me to it Bobby

Edited January 9, 2013 by mcweather

[ITSY]

Slight upgrade on models so far. Much better UKMO, GFS op produces frontal and convective snowfall between sat and tues (then goes the way of the pear but not as badly as the 06Z)...over to GEFS then ECM.

Still lots of positives and potential, especially if ECMWF sticks to its guns.

[bradymk]

Ok so GFS an improvement but we need more. GP mentioned the NOGAPS following GFS on 00z output before ditching it. Well it's 12z is currently coming out and it once again doesn't follow GFS and its even better than the 6z. Comparing the same timeframe to this mornings ECM and they look remarkably similar. Upstream pattern is so important here. And the NOGAPS at +144 is a cracker, i know it is the NOGAPS but still encouraging. PS. the GEM was so similar to ECM this morning so it will be interesting to see what it does, trickling out now.

Edited January 9, 2013 by bradythemole

[mountain shadow]

A good sign surely that the GFS has moved somewhat and prolongs the cold.

On the poorer side the Iceland based high appears fragile with more of a mid Atlantic based high which would allow energy over the Top and sink or topple the ridge.

A step backwards i feel so far and await the ECM with fingers crossed.

[TEITS]

I know its the 12Z NOGAPS but lets be honest the other models are so inconsistent might aswell post this.

Based on my experience when we have such disagreement normally it means none of the models are right.

[Mark Bayley]

The NOGAPS 12z is now out, and is better than the 6z, with greater heights around Southern Greenland/Iceland. Not the best of models though, soon to be replaced. The GEM should be out soon however.

Edited January 9, 2013 by Mark Bayley

[SnowObsessor90]

Surely if this run came off, wouldn't it go completley against and contradict the supposed SSW event???

Well people said similar when models first started picking on the Atlantic charging through back in December so it certainly isn't a possibility that should be discounted.

Edited January 9, 2013 by Anonymous21

[tight isobar]

Gfs,12, again imo over keen ön atlantic. Very interesting Ecm this evening all to play for, thats for sure.

[rory o gorman]

As i said earlier the 12Z ens are going to play a massive part in the gfs recognition of shortwaves under greenland.If support is there i will become worried

[Methuselah]

[abruzzi spur]

I went Aldi earlier and they had snow shovels for sale outside the entrance that weren't there 2 weeks ago, coincidence?

Major retailers, particularly food retailers, all spend significant sums of money on short and medium term forecasting so that they can manage their supply chain. I imagine that if you go to most of the big retailers, including DIY and garden centres, over the next day or 2 you will see winter kit appearing.

Either that or Aldi have their own weather model that looks very similar to the ECM and GFS etc, but is just different enough to avoid them getting done for copyright infringement and is significantly cheaper!

[Staffordshire]

Got a feeling there will be a northward movment of satardays snowfall, manchester brought into the firing line more, also the block being much stronger and stalling the front for longer

haha i did mention this on page 5 of this thread!

[snowstorm445]

I really can't understand the GFS. There is a clear opening around 160 or so hours and it insists on keeping the two highs apart, even when the lows retreat. It seems to be doing all it can to ensure the survival of south westerlies (even later on in the run).

[andy_leics22]

12z NOGAPS is MASSIVELY better than it's 00z output!

They are like chalk and cheese

00z...

12...

[Cheshire Freeze]

As i said earlier the 12Z ens are going to play a massive part in the gfs recognition of shortwaves under greenland.If support is there i will become worried

It's not the fact that these shortwaves are there (though that certainly doesn't help matters), it's the timing and phasing of these shortwaves which undoes the pattern.

Still model uncertainty which makes me wonder why I stayed up until ECM had finished. Was mid afternoon when I arose from my pit!

[Liam J]

After some stonking charts from the GFS over the last few days the 12z is an absolute horror show!! Really hope it's offered minimal support from the rest of the GEFS suite. UKMO looking good if not perfect, over to you ECM

[Ian Brown]

I would expect the reverse – Southward movement of the projected system on Saturday.

Surely if the GFS is right in FI – and FI is probably pretty early right now – then it goes against all teleconnections.

[Habsish]

Low pressure

So why do we now call it a shortwave if it is a low pressure? Confusion of terms? What about high pressure?

H

[Southender]

So we are about 72hrs away from the first "potential" widespread snow event of the season. Details to be firmed up but anywhere South of Manchester could be in the frame. As usual this will chop and change and certain areas may get more of a wintry mix but its nice to see.

[Methuselah]

Major retailers, particularly food retailers, all spend significant sums of money on short and medium term forecasting so that they can manage their supply chain. I imagine that if you go to most of the big retailers, including DIY and garden centres, over the next day or 2 you will see winter kit appearing.

Either that or Aldi have their own weather model that looks very similar to the ECM and GFS etc, but is just different enough to avoid them getting done for copyright infringement and is significantly cheaper!

Aye, Tesco had them in December, too...Anyhoo, I won't be paying much attention to FI; there seem to be far too many about-turns in the GFS, just now...

And another reminder:

[Ali1977]

GEM looks like its showing much colder 850s this weekend on 12z

[Bobby]

The GEM is looking good already at +96, a cold run coming up I think. Although it takes Saturday's low so far S the precip misses the UK.

Uppers for Saturday night, very cold

[Lynxus]

Truly atrocious GFS run in the longer term. It has the most bizarre obsession with ensuring south westerlies when there is ample opportunity to ridge northward. I will be interested to see if this operational run is part of the trend or just the mild obsessed outlier.

Its because the GFS has a lot of data with the west in mind. It NEVER! handles easterlies well.

With that said, It shouldnt be discounted. What it shows is very much possible. However with a strong eastern influence the chances are that any LP's or shortwaves will be greatly overdone in the model almost up to 36 hours out.

I would take what the GFS says seriously but would remove a bit of strength from the west.

[Liam J]

GEM rolling out and looking good so far, band of snow crossing the country on the 12z with bitterly cold air flooding in from the east.

Edited January 9, 2013 by Liam J

[snowmadchrisuk]

Tonight's ECM is probably going to be one of the most anticipated model runs ever! The UKMO looks good, the 12z GFS looks average but a lot better than the 06z run.

The other important runs to look out for will be the 12z BOM model run and the GEM 12z run.

Both of those showed stonking runs on their 00z's

So if they follow on with their 00z theme then we could be in business. Just a little off-topic mention here... I went Aldi earlier and they had snow shovels for sale outside the entrance that weren't there 2 weeks ago, coincidence?

Gonna be visiting Leicester on Monday , hope the trains aren't cancelled as already have ticket .... All Snow Saturday according

To the GFS