Model Output Discussion 17th Dec.2013-12z onwards.

[Summer Sun]

UKMO has the low on Tuesday at 940mb

 

 

GFS gets it very close the the 129 year old record

 

[cooling climate]

Really like the direction the 12z FI is taking us. It also ties in with what the

CDAS 200mb temp anomalies are showing with warming to our NE.

Of course its a work in progress but something to follow perhaps.

[Captain Shortwave]

So we want a nice flat pattern with no height rises toward the pole to aid future blocking prospects?

Well I didn't say that but the type of blocking shown on the GFS is completely useless for us as it pretty much puts slow moving troughs in our vicinity bringing average and very wet conditions. The set-up doesn't solve our fundamental problem which is the massive blob of purple over Canada and Greenland. 

[Mucka]

Really like the direction the 12z FI is taking us. It also ties in with what the

CDAS 200mb temp anomalies are showing with warming to our NE.

200mb 21.12.13.gif

Of course its a work in progress but something to follow perhaps.

 

Agreed, very much a work in progress.

All we can hope to see in the output (other than deep cold obviously) are continued signs of blocking trying to establish itself. That will be tough with low heights around Greenland and the Atlantic wanting to override the signal but it could also be quite a messy complex one that, if not deeply cold or blocked,  is potentially snowy one especially for Northern parts at times.  

 

My main concern is that the Azores high manages to gain some control and all that Atlantic energy is sent NE overriding any blocking signal completely rather than allowing for transient ridges and southerly tacking lows.

[cooling climate]

For some reason that animation does not seem to be working so

I will try again.

Pity the 12z run did not carry on for another week for we would almost

certainly see a potent easterly setting up. Of course at over t400 hours

away it is just a dream but with the 200mb profile the way it is then maybe

not so far fetched.

 

Still does not appear to be working but trust me there is a warming around

Spitsbergen and the end of the animation.

Edited December 21, 2013 by cooling climate

[Summer Sun]

Not much change from UKMO this afternoon

 

Respite from the strongest winds Wednesday, Thursday next low returns 28th

 

[Mucka]

Well I didn't say that but the type of blocking shown on the GFS is completely useless for us as it pretty much puts slow moving troughs in our vicinity bringing average and very wet conditions. The set-up doesn't solve our fundamental problem which is the massive blob of purple over Canada and Greenland. 

 

Yes it could be that the type of blocking (if any) that sets up doesn't influence things enough or in a way that benefits us but then again it may well benefit us, even with that "blob of purple" over Canada. 

I know people look for the beautiful looking synoptic charts of a cut off Greenland high or nice Scandinavian high and want to see the deep blue 850's entrenched over the UK but sometimes months with big snowfalls are not like that, they are messy affairs with temperatures just a little below average.

 

I think people get too hung up on the PV these days. It is all chicken and egg. Will the PV prevent blocking or will blocking shape the PV?

There are more to UK winters than SSW's and Greenland highs is all I am saying and while I was talking about ridging to our East and increased opportunities for blocking into January others were saying it was zonal out to the end of time. Now that we see this ridging being modelled it is a case of, "Boo, wrong place, won't help us."

 

Well TWT on that but I fancy there will be some decent snowfall around come January even if there isn't the prolonged cold and the kind of blocking most are looking for. 

I wouldn't stake my life on it though. 

Edited December 21, 2013 by Mucka

[shedhead]

Back from a couple of days off from model watching and hoping (rather against hope in all honesty) to see at least some changes being signalled in the overall pattern, but alas it's just not to be.  That said the lack of 'wintry' interest is still balanced to some degree by what looks like being a very lively spell of pre Xmas weather...and that's putting it mildly!  OK not a beast from the east, but most certainly a beast from the west, with a potential centre of sub 930mb!!

 

What we're probably (and I sure some are saying hopefully) seeing here is an example of GFS's persensity to over deepen many LP's, but even so this has all the hallmarks of a significantly disruptive feature at any time of the year, let alone on Xmas Eve!!

 

[JoeShmoe]

A 929mb low on Christmas eve and the majority of model commentary is still on if we might see a snowflake at T+360

 

*sigh*

[Mucka]

A 929mb low on Christmas eve and the majority of model commentary is still on if we might see a snowflake at T+360

 

*sigh*

 

Is this your attempt to redress the balance and be informative?

Why don't you post a detailed description of likely conditions with charts etc and talk about the part of MO you want discussed instead of sniping? 

Edited December 21, 2013 by Mucka

[Severe Siberian icy blast]

Tonight I feel as we have made a significant step to northern blocking , not only do we have the artic high well in place , we also have a split vortex , which given the strength of the vortex is remarkable , what we also have hear is ridging into Scandinavia , which is very close to a undercutting scenario , no doubt in my eyes that we are close to wintry set up going by the gfs fi this evening , surprised by the negativity recently , but i think we will begin to see changes as we going to the new year.

This is a very good chart . If we can get the energy going under the block then we have a scandi high in place, a split vortex , high lat blocking , and lots of energy coming off the Atlantic going under . Which spells a very snowy picture .

[bluearmy]

Gem day 10 polar profile not without interest as well.

As I said on the in depth earlier, ridging well to our ne could well be the realistic route to deep cold, given the arctic high and strong Atlantic jet.

[Dampdorset82]

Tonight I feel as we have made a significant step to northern blocking , not only do we have the artic high well in place , we also have a split vortex , which given the strength of the vortex is remarkable , what we also have hear is ridging into Scandinavia , which is very close to a undercutting scenario , no doubt in my eyes that we are close to wintry set up going by the gfs fi this evening , surprised by the negativity recently , but i think we will begin to see changes as we going to the new year.

This is a very good chart . If we can get the energy going under the block then we have a scandi high in place, a split vortex , high lat blocking , and lots of energy coming off the Atlantic going under . Which spells a very snowy picture .

image.jpg

I agree, my earlier post suggests that we are entering a real change in the pattern and the storms over the next week start that process. The artic high will be crucial regardless of where the chunk of PV sits saying that the PV could be great for the under cut scenario as you refer too.....looking forward to it

[Summer Sun]

GEM has the low at 935mb on Tuesday

 

 

Calmer Wednesday and Thursday

 

 

Next low seeps in on the 28th

 

 

We end the year with another low waiting in the wings

 

[Tedward1982]

I have a feeling this winter is going to get very interesting, newbie, so not a "pro" however my taking on the models recently suggests to me that we have had a sequence of - Boring nothing weather for a few weeks, then (as we are in now) a wild period, soon to be followed by a potentially blocked two thirds of the winter. Good model watching, to be honest I am not an expert, no idea what will happen, just think these events are highly interesting. 

[bluearmy]

Gavin, is that all you can say about that day 10 gem ? 'Another low waiting in the wings'

[Summer Sun]

Latest NAO update continuing to show a trend downwards as we end 2013 and move into 2014

 

 

Latest AO update heading down as well with 2014 probably starting negative

 

[Jason M]

Hmm, the ensembles suite looks very different in FI. A few easterly options have been popping up recently which I've largely ignored in amongst the many many zonal charts. However, there is a much stronger signal now emerging.........

Be interesting to see if this continues. Wish I was on my computer as I'd post a few charts ( there are some good ones).

Jason

[The Northern Ramper]

Gavin, is that all you can say about that day 10 gem ? 'Another low waiting in the wings'

He doesn't have your understandings of the charts.

[IDO]

There are ten ensemble members showing an Arctic High by T384; at that range that is a good trend.

 

There are some very good runs showing a cold upper's feed:

 

Some:     

 

 

 

Not seen that sort of signal for a while. Potential showing up is good, now need consistency.

Edited December 21, 2013 by i'm dreaming of...

[Summer Sun]

The met office currently expect this approaching low to hit around 934mb

 

 

70 to 90mph gales in NW Scotland on Tuesday winds in England and Wales start to ease after peaking around 60 to 80mph around the coasts of England and Wales, less windy for all on Wednesday with a few flakes of snow over high ground

[That ECM]

Gavin, is that all you can say about that day 10 gem ? 'Another low waiting in the wings'

And just a bit more condescending BA. This is exactly why people refrain from posting. Fear of a reprimand.

[Skeggy Winter Storm]

GEM has the low at 935mb on Tuesday

 

 

Calmer Wednesday and Thursday

 

 

Next low seeps in on the 28th

 

 

We end the year with another low waiting in the wings

 

hi Gav as a newbie still leaning on the last chart the low to the sw of us if that goes under us is that good for cold is that an undercut low

[Mucka]

ECM 120h still handling the development of that next Atlantic low very differently to UKMO and GFS in that it doesn't have the rapid development. So support for its morning run to some extent.

 

[bradymk]

ECM sticking with its 00z output or rather still in disagreement with GFS & UKMO. interesting. GEM caught my eye too aswell as GEFS. Maybe look towards NE as Nick said?

Edited December 21, 2013 by bradythemole