237 replies to this topic

[warrenb]

Ah now you have hit the nail on the head, no high latitude blocking AFFECTING THE UK, there is plenty of blocking at high latitude, just not in the right place for us yet. We all know that most thing shift East nearer the time.

[Tim Bland]

My mistake..Thanks for deleting. See below for (hopefully this time) the low there on the 06Z

Attached Thumbnails

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[Geordiesnow]

warrenb, on 18 January 2012 - 16:53 , said:

So we are all panicking about a monster low that wasn't even there 6 hours ago.

Even if that low was not there, I still can't see much for snow fans to be even hopeful about, even a NW'ly on the output is a very tame affair because of the lack of cold air this year due to the global set ups that have been occuring!

I noticed a post above saying the UKMO 120 hrs have got good cold potential but I been reading those type of posts since past xmas now and quite frankly its tedious now. You can see clearly that even if you got a marginally weaker PV, some sort of height rises and a large russian high, unless it all comes together then theres no gurantees of a cold set up with proper cold uppers and when looking at the charts we could get an Northerly or Easterly but would you even bet that the -10hpa would even touch Scotland, look back at the archieves and you can see because of the persistant southerly winds from the Russian high for most of the winter, the upper air temps are quite mild and you will see from the archieves of more deep cold air.

Still, some interest in the other aspects of winter which I did enjoy at times during December and that is the models are showing some weak PM WNW-NW'lies and it could be quite gusty at times, nothing severe but some weather to speak of. The message is the further South and West you are the more likely you will be cloudier with little sunshine due to the Azores high not being too far away whilst the further North and East you are it will be brighter with showers coming in from the Atlantic in the NW.

[happy days]

warrenb, on 18 January 2012 - 17:02 , said:

Ah now you have hit the nail on the head, no high latitude blocking AFFECTING THE UK, there is plenty of blocking at high latitude, just not in the right place for us yet. We all know that most thing shift East nearer the time.

Yes the high latitude blocking is sat way to our NE its been there pretty much right throough January but due to the super strong PV it has made little if any impact on our shores.

[Snow Guy]

I'm struggling to believe the GFS past 96, i genuinely feel more is going to be made of the heights to our north west on or around the 22nd-23rd.

[THE EYE IN THE SKY]

Slightly confused by some of the comments. For starters I thought we all knew that between +96 to +144 nothing exciting was going to happen apart from a cool/cold NW,ly. The LP that many mention is nothing new either but its what happens next is whats uncertain.

When you look through the GEFS ensembles towards the last few days of Jan you see an incredible number suggesting blocking with many of these showing E,lys via blocking to our NE. Now this is why the Met O are suggesting two scenarios because its a classic E Vs W battle.

I will add it may not appear so but we are in a completely difference situation now compared to early winter.

At the moment if we are to see a prolonged cold spell i.e Met O forecast then in my opinion it will arrive via blocking to our NE rather than Greenland. If you notice the Met O say NE/E,lys but if it was a Greenland HP N,lys are also possible.

Edited by THE EYE IN THE SKY, 18 January 2012 - 17:21 .

[i'm dreaming of...]

All the models are showing the rest of Jan to be snowless and probably average temp wise for the south. There may be some transitional snow for others but that is the best we can expect. GFS FI takes us into a very poor setup for Feb with mild temps and no snow, even for Scotland. You can see where all the action is:

http://nwstatic.co.u...a7a112c012bb93;

We have missed it by a quadrant either way. What looks even worse is that pattern looks blocked giving rise to a very static looking Feb where all the action is a thousand miles away either East or West.

Edited by Paul, 18 January 2012 - 17:42 .
Removed off topic lines

[danm]

THE EYE IN THE SKY, on 18 January 2012 - 17:19 , said:

Slightly confused by some of the comments. For starters I thought we all knew that between +96 to +144 nothing exciting was going to happen apart from a cool/cold NW,ly. The LP that many mention is nothing new either but its what happens next is whats uncertain.

When you look through the GEFS ensembles towards the last few days of Jan you see an incredible number suggesting blocking with many of these showing E,lys via blocking to our NE. Now this is why the Met O are suggesting two scenarios because its a classic E Vs W battle.

I will add it may not appear so but we are in a completely difference situation now compared to early winter.

At the moment if we are to see a prolonged cold spell i.e Met O forecast then in my opinion it will arrive via blocking to our NE rather than Greenland. If you notice the Met O say NE/E,lys but if it was a Greenland HP N,lys are also possible.

Agreed. I think we have all written off any significant cold and/or snowy prospects in the short to medium term. It is the end of January and into February that is providing most interest - through the encouraging background signals reported on by the likes of Glacier Point etc. The Met Office are also clearly seeing these signals as their medium range outlook highlights the risk of a cold and snowy scenario potentially cropping up as we head into February.

[Cloud 10]

Very little support for the gfs 12z op run from the ensembles later in the run regarding 850 temps.

Yet again the gfs op. in outlier country. at least for aberdeen

gfs op.+240> ensemble mean +240>

Edited by Cloud 10, 18 January 2012 - 17:47 .

[Zakos]

Looking at the ensembles in FI, the only real outlier is the mean.

Majority of ensembles go for very cold, or very mild weather. The ensembles are roughly split equally. This appears to fully back up the met office long range output.

Ensemble support for the colder evolution has increased somewhat since the 06z aswell which is encouraging. Only 2 or 3 ensembles have us in the deep cold from the 23rd, the majority have the cold arriving in the last few days of jan (again backing up the met office)

I will be watching these ensembles carefully these next few days, as comparing today's 12z ensembles to yesterdays 12z ensembles, support for the colder evolution has increased considerably.

[nick sussex]

Last night the ECM was the first model to go with this suggestion:



All the output has now followed with this trend so I'd pay particular attention to what it does this evening at around 120 to 144hrs.

[Frosty039]

The Gfs 12z operational run has just painted a very misleading picture of where the pattern will be in 10 days time, the ensemble mean shows much colder air entrenched over the uk and much of northern, western and eastern europe with the polar front jet over northern spain. I refuse to believe things will unfold as the op run suggests as it is just a throwback to how things looked in late november and early dec when we had a cold stratosphere. I would expect a much colder and more blocked pattern to be developing over the next 10-15 days with the jet much further south.

Edited by Frosty039, 18 January 2012 - 18:24 .

[nick sussex]

Regardless of the earlier differences the end result looks like the trough over the UK.

And from there its going to be whether the high to the east can win the battle by eventually sending this packing, just signs on the ECM 168hrs of some forcing on that trough, note the shortwave developing on its southern flank.

Will this disrupt sending some energy se'wards.

[Weathizard]

ECM so far looks relatively similar at t168+ to the GFS slight differences though, I suppose very slight differences can make a massive difference though

Edited by Weathizard, 18 January 2012 - 18:41 .

[THE EYE IN THE SKY]

Weathizard, on 18 January 2012 - 18:40 , said:

ECM so far looks relatively similar at t168+ to the GFS slight differences though, I suppose very slight differences can make a massive difference though

One big difference is the positioning of the block to the NE.

http://www.wetterzen...cs/Recm1681.gif

[karyo]

Not a good ECM!

http://www.meteociel...map=0&archive=0

The high pressure in Russia is too far south and unfavourably tilted. As for the Atlantic, the lows keep riding the high pressure effortlessly.

Karyo

[happy days]

THE EYE IN THE SKY, on 18 January 2012 - 18:44 , said:

One big difference is the positioning of the block to the NE.

http://www.wetterzen...cs/Recm1681.gif

Which has been there for weeks and simply cant get a sniff due to the PV and associated jet energy dave.

[Anti-Mild]

THE EYE IN THE SKY, on 18 January 2012 - 18:44 , said:

One big difference is the positioning of the block to the NE.

http://www.wetterzen...cs/Recm1681.gif

It's like water torture watching the Russian High try to inch closer! At this rate it'll get here sometime in May (which would be fine by me!)

As has been the case for the past 2 weeks, until the models get a handle on the impacts of the strat warming and the dispersal of the PV, anything past +120 is to be ignored - unless it shows something cold!

Edited by Anti-Mild, 18 January 2012 - 18:51 .

[Gavin D]

ECM looks mixed late on tonight

Edited by Gavin D, 18 January 2012 - 18:56 .

[Tim Bland]

Looks ok at 216. An Atlantic ridge, lower heights over Spain and lots of cold to our north and east. Wouldn't take many tweaks to make it a great chart - - see above ^^^^^

Edited by Tim Bland, 18 January 2012 - 18:56 .