ECMWF: Open the atlantic bay doors UKMO.

UKMO: I'm sorry EC, I'm afraid I can't do that.

*****

GFS: Scandi high in range, lock on. ******'s not even changing course.

NAVGEM: I aim to misbehave!

 Sorry mods, that I keep doing this. Its been a long dull winter. 

Ties in with what Ian F was saying last night

I understand that PV disruption/obliteration makes it more likely for cold synoptics to set up for the UK.  However, as notable as the Arctic High is, and as complete as the PV split is, if the North American arm of the PV continues regardless, as it seems to be, then I can't see how that benefits the UK in terms of potential wintriness..... Happy to be corrected though.

Andrew 

With further height rises over the high Arctic/Pole being signalled for from day 8 onwards, it seems to me that the probability of an Arctic outbreak affecting the UK sometime in the next month is actually on the high side, considering the natural winding-down of the PV coupled with strat warming impacts.

The confidence in such an event for any given week is, however, very much on the low side!

The handling of the burst of westerlies next week is crucial, and we've seen enough corrections towards trough disruption with energy sliding away SE for it to be reasonable to look out for the same next week - much like the 00z GFS op run produced, but with room for a greater amount of energy going SE with less remaining to our NW.

If we don't get that, then we look to the next Arctic High in search of our lucky break.

Well if we can't get any blocking now, let's have it in the summer so we get another goodun like last year

Or 2012...

yeh, we dont want northern blocking in summer.  No thankyou.

http://www.theweatheroutlook.com/charts/gefs/gefsens850London0.png

was on the mild side for that time period as well

http://expert-images.weatheronline.co.uk/daten/proficharts/en/2014/01/22/basis06/ukuk/rart/14012618_2_2206.gif

http://expert-images.weatheronline.co.uk/daten/proficharts/en/2014/01/22/basis06/ukuk/rart/14012700_2_2206.gif

JFF  Parts of the North and West might see some  through Sunday

http://expert-images.weatheronline.co.uk/daten/proficharts/en/2014/01/22/basis06/ukuk/rart/14012900_2_2206.gif

http://expert-images.weatheronline.co.uk/daten/proficharts/en/2014/01/22/basis06/ukuk/rart/14012906_2_2206.gif

http://expert-images.weatheronline.co.uk/daten/proficharts/en/2014/01/22/basis06/ukuk/rart/14012912_2_2206.gif

J F F  Wednesday could actually feel like winter

http://www.wetterzentrale.de/pics/Rtavn1741.png

http://www.wetterzentrale.de/pics/Rtavn17417.png

http://www.wetterzentrale.de/pics/Rtavn1743.png

Because the mean is right in the middle of the zone of Cold windy and wet (the worst kind of winter weather), rather than Very snowy cold and crisp.

I agree. Atm, it is looking cold/wet/unsettled with any wintry ppn confined to the hills and perhaps at brief intervals on higher ground. I'd prefer mild and wet rather than cold and wet.

ENS don't look great for any big freeze.... http://www.weathercast.co.uk/services/ensemble-forecast.html

Very important 12Z's coming up I think, can we see a repeat of that UKMO T+144 chart

Anyone else have trouble viewing charts, NW,Wetter,Meteo all down?

Clearly lots of people feel these 12z's have a lot riding on them lol

K Outlook for Monday 27 Jan 2014 to Wednesday 5 Feb 2014:

Probably windy and changeable at first, with sunny periods and showers or longer spells of rain, some heavy. There may be snow on northern hills, and a risk of hail and thunder. Temperatures near normal at first in the south but generally turning colder from the north.There may be a colder interlude around midweek, with easterly winds and wintry showers in the  north east of the UK. However, a return to westerly winds is expected from the end of the week, with further outbreaks of rain, hill snow in northern Britain and strong winds. There will be some drier and brighter weather too, the best of this most likely in the south and southeast of the country, and there will be a continuing risk of local overnight frost and fog.

Updated: 1136 on Wed 22 Jan 2014

METO Take on next week and particularly mid week.A bit more optomistic than the last GFS runs.Interesting to see the METO12h run.

The strongest indicator this winter ha sbben the QBO

The QBO (Quasi-Bennial Oscillation) is a quasi periodical oscillation of the equatorial zonal wind between easterlies( -) and westerlies(+) in the tropical stratosphere.It is  measured at 30mb height.

The average length of the the oscillation is around 26-29months.It is  however asymmetric,with the amplification of the easterly being nearly twice as great as the westerly.In addition on average the easterly cycle lasts o about 30% longer than the westerly.

It is possible , looking at the data set to work out for each year (1953/4 to Dec 2013) to work out the type affecting each year and the strength and length of each cycle.

The summary of my analysis is

1.There is  no correlation beween postive and negative cycle years and the winter CET.The average across the series for easterly( -years) is 4.3 c and the + years are 4.3 too.!

2.If  a subset of years with particularly high +or - values is used the relevant CETs are 4.27 v 4.26.

3.Using a measure which  combines number of months in a cycle with values of each month  all mothst then selecting the higher value  years  gives an avearge CET of 3.8c for strong -ve years and 4.1  for strong +v years unlikely to be statistically significant.

4.The overall conclusion is clear.I seems that on its own it can't explain winter circulation patterns.It may be that this year in the absence of any other indicators then it has played a part but  could b  other little known facts as well.!  

http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=186&mode=0

Thats  as  far as GFS 12h brings in any easterly!

Quite an interesting run tonight with a different take on events post 123hrs

This chart grabbed my attention.

http://cdn.nwstatic.co.uk/gfsimages/gfs.20140122/12/165/h850t850eu.png

Quite a stark difference from the previous charts, but has got me questioning the area just to the north.  With LP darting off to the south and L:P anchored way out west, could this be the start of a more better aligned Scandi high?

At this range you just need to look for the big players and where they are forecast to sit rather than the detail.

Will keep an eye on this going into the next run to see what the models think of it then.

UKMO has a 955-960mb just NW of Ireland on day 4. GFS has a 945mb low just S of Iceland.

That makes all the difference regarding how far the LP slides by day 6... and how much work the Atlantic has to do to bring back the westerlies thereafter.

I'm kind of waiting for the Atlantic onslaught post-day 6 to become disrupted and produce a slider low in the output, but I'm not sure if it will happen or whether we'll be waiting for the PV energy to subside a bit first.