Usual scatter this morning but low confidence in any particular solution so for now I'm sticking to the form horse and the mobility continues into the new month.

Shannon is putting it about at the moment. GFS has gone flatter but ECM maintains the more amplified pattern and gives a better northerly. The Azores high again seems to be the spoiler and unless we get pressure spilling down from the pole, I cant see any sustained cold

The Azores High certainly is a stubborn so and so.  Even when it's pushed aside briefly it pops straight back into place immediately after, so all we can look forward to are transitory NW sliders and maybe, if we're very lucky a couple of days of Northerlies.  I'd be interested of any of our more learned members have any thoughts on the processes that can move the Azores High out of the way.

Yep

ECM out on its own with opening the northern gates.  But even here shortwave after shortwave over the top will make this a 2 day affair.

No sustained cold whilst the massive AH sits there.

Only ECM sticks with the presence of the polar high. 

In my view the potential wanes this morning but it is just one run.

HERE IS MY LATEST ANALYSIS FROM THE OUTPUTS OF THE WEATHER COMPUTER PREDICTION MODELS FOR TWO WEEKS FROM 8AM TODAY THURSDAY JANUARY 22ND 2015.

NEXT UPDATE FRIDAY JANUARY 23RD 2015 08:00

THE CURRENT GENERAL SITUATION An area of slack winds will be maintained across the UK today followed by a trough of Low pressure moving in from the west tomorrow.

MODELS-2 WEEK HEADLINE Changeable with rain at times but some drier spells too. Less cold. Possibly turning more generally unsettled and colder again later with some snow in places, especially over the North.

THE JET STREAM ENSEMBLE FORECAST The Jet Stream Forecast shows the trough in the flow over Europe receding East and then settling into a West to East motion across the UK with occasional tilts slightly North of West over the South of the UK on it's way to Europe later in the period.

GFS OPERATIONAL The GFS operational today continues to show the UK under the influence of West or NW winds around a strong Azores Anticyclone and deep Low pressure areas moving East and SE to the North and East of the UK. Things change little over the course of the run this morning with all areas seeing spells of rain on successive cold fronts passing over and followed by colder NW winds and wintry showers most prevalent towards the North and East of the UK especially later in the run.

THE GFS CONTROL  The GFS control run mirrors the operational run well with strong confidence in West or NW winds dominant across the UK over the enxt couple of weeks. Temperatures will fluctuate day to day but it will never be desparately cold with wintry showers between the rain bands restricted to the North. At the end of the run the model deepens the unsettled weather over the UK with all areas seeing strng winds and rain and more coherent colder weather filtering into the North later.

THE GFS CLUSTERS The GFS Clusters today show very mixed messages none of which show any particularly cold evolution for the UK. We have a 30% each spread in Low pressure to the North and a strong Westerly flow likely to a High pressure cell to the East and a Southerly flow across the UK with coldest conditions in the continental flow over Eastern Britain to Westerly winds with High pressure close to the South which would mean mild weather for all.

UKMO UKMO this morning shows High pressure close to the South and SW at the start of next week with further weak cold fronts crossing East across the UK with some rain chiefly over the North followed by fresher weather with patchy night frosts and bright days.

THE FAX CHARTS The Fax Charts show a series of fronts moving East and SE across the UK over the next 5 days with alternating spells of rain and milder air mixed with short periods of colder and clearer conditions with some wintry showers in the NW and frost at night in places.

GEM GEM today shows a spell of west and NW winds strengthening later around a large Azores anticyclone and strengthening Low pressure areas moving East and SE across the North Sea and NW Europe later. Spells of rain followed by clearer and colder conditions will continue across the UK throughout the period with the depth of the cold periods increasing later with more frequent incidences of wintry showers for may later next week.

NAVGEM NAVGEM also keeps the same trend and pattern as West or NW winds carry spells of rain followed by colder and clearer conditions with wintry showers in the NW. As with GEM the colder NW winds become more coherent for the rest of Britain instead of just the NW later next week with wintry showers between further rain bands extending to all areas.

ECM ECM this morning continues yeaterdays theme of West and NW winds around a High pressure area persistent to the SW of the UK. Southern and Western areas will maintain the driest and mildest weather with the colder air between successive cold fronts coldest over the North and NE where some wintry showers ccur at times. As of yesterday the run indicates a passage into much colder weather for all in a more direct Northerly feed late in the run with wintry showers of sleet and snow for all for a time but it looks like the Azores High will once more send a toppling ridge across the UK with milder westerly winds returning soon after Day 10.

ECM 10 DAY MEAN The ECM 10 Day Mean Chart today continues it's promotion of cold NW winds around Low pressure over Scandinavia in 10 days time with wintry showers and rather cold weather most likely across the UK though it never looks like becoming desperately cold.

NOTABLE TREND CHANGES FROM PREVIOUS RUNS The trend today is for the models to of slightly watered down the return to cold North or NW winds later mostly due to the strength of the Azores High.

MY THOUGHTS It appears that the spell of somewhat less cold conditions alternating between cloudy conditions with some rain and brighter and fresher conditions with some sunshine looks set to be dominat across the UK for some considerable time to come. There is still indications that a more coherent dip into rather cold NW or even North winds later for all areas as Low pressure sinks South over Europe and veering winds as a result so that most places could see some sleet or snow showers later. However, the problem continues to lie out to the SW where the Azores High continues to have one of it's strongest strangleholds on UK conditions in Winter I have seen for years. This coupled with a persistent strong vortex up to the NW of the UK shortens the duration of any cold interventions we have from the North and despite the cold look of some of the synoptics in 10 days time particularly from ECM it looks very transitory as the Azores High fails to ridge sufficiently North over the Atlantic and the inevitable toppling of a ridge from it cuts off the Northerly feed to bring milder westerly winds back fairly quickly. GFS doesn't offer much in the way of hope for cold in it's clusters this morning all showing variations of fairly mild options unless the clump showing High pressure East of the UK moves on later to provide something more fruitful. However, all the above is decribed as just one run in a very fluid situation longer term but one thing is for sure in that unless the Azores High moves or weakens then any excursion into cold weather will be short and less sharp across the UK.

The op runs are a bit naff this morning apart from ECM which offers at least a short spell of interesting conditions.

It's also the only run showing much of a troposphere-level response to the vortex displacement in the stratosphere (over to Siberia), this being a substantial weakening of the Canadian vortex. GFS shows it becoming a bit stretched but it never really gives way.

This ties in with GFS going for a flatter jet days 7-10; the Canadian vortex encourages LP development in the western N. Atlantic and also boosts the jet strength, preventing that sharp dive south that ECM keeps coming up with.

So the way I see it, this is to at least some extent a case of whether there will be much of a stratosphere-troposphere coupling or not. 

The rest comes down to the activity on the subtropical jet and the extent to which it engages with cold air across Canada, getting a boost in intensity and creating deep lows that 'plow the road' in the Atlantic. This has been a major player in cutting short our colder spells so far this winter, and I remember the Met Office talking about subtropical jet activity (or something along those lines) when discussing the reasoning behind calling a winter that was lacking in cold outbreaks for at least the first month or so and probably longer. Kudos to them for that one!

GEFS feature about as many runs hitting -7.5 to -10*C 850hPa temps over London as I've seen all winter, so they are at least exploring the potential, though curiously, a lot of the -10*C ones are in early February. A slower response to the strat. events? Possibly... or it could be the influence of a new strong MJO wave through phase 7 toward phase 8 being explored by some of them.

Whatever's the case, we're certainty in a 'waiting and wishing' period at the moment and I for one have been turning my attention more to other things in life - the way the models behaved with the cold spell we're now nearing the end of was disappointing to say the least, and just another story in what seems to be 'the winter of the dangling carrot'. Having joined TWO in 2008, this is my first time going through such a winter of red herrings. How on earth did people survive on here in the late 90's and early 00's 

The ECM continues to be the most amplified of the models. At day 10 the GEFS, NAEFS and GEM ens are overall flatter.

ECM ens anomalies:

NAEFS:

Maybe something inbetween the two might be a good bet. Meaning a chilly NWly flow for a time, most unsettled in the North with a risk of wintry showers, snow over high ground. Anything particuarly cold or prolonged looks a long shot however with signs of the ridging Azores high toppling towards the UK later and the pattern flattening.

6Z has some real cold air moving into scandanavia, I'm impressed with the run. Some stuff still has to come together but I think the potential of this cold spell is superior to any spell this winter so far.

Also what the hell is it with people and mountain orcs? 

http://modeles.meteociel.fr/modeles/gens/runs/2015012206/gensnh-10-1-204.png

Some good GEFS members but a lot also have the Azores pushing back

I think it could be one of those situations where we see multiple attacks from the NW, I don't think a failed first attempt means we won't get a cold spell, I mean 3 attempts seems to be the usual. 

It's definitely one of 'those' winters now I reckon. I think if that Azores high is going to do anything useful it'll ridge NE in Feb - like in 1984. It just doesn't seem to like the idea of taking up residence over Greenland sadly (or moving anywhere for that matter!)

Well the signal is extremely strong on the ECM and EPS, less so on the other models. ECM is slightly superior at longer ranges too, and it isn't as if there is no agreement from the GEFS suite, the 6Z op was pretty close to something interesting too.

Hi all,

Here's today's video update;

Azores High Staying In Control

http://www.gavsweathervids.com/

Could be another cold snap next weekend (31st Jan & 1st Feb)

Where did you get the control run from? 

By February 1/3 of runs below -5C 850hpa in London, 2/3 runs below about -2.5C

In Glasgow its even better, 2/3 runs below -3.5C, 1/3 runs below -6C.

For Wick we have 2/3 runs below -4C, 1/3 runs below -7C.

Accuweather Pro.

james - the ECM op made a pigs ear of the strat split at the turn of the year compared to gfs. This evolution to displaced Siberian vortex was trailed by the gfs prior to day 10 when we are able to see ECM version. Clearly, a couple of days ago, ECM decided that this mid/upper strat profile would downwell almost immediately into the trop. andrej on NW showed a 3D representation of the upcoming displacement which showed the trop euro trough being a direct result of the upper strat activity. 

Now ECM has kept with the solution (op and ens) whilst gfs toyed with it on a couple of runs before deciding it would not be as deep nor as far west as a consequence. More Azores influence.  I wonder if the extra vertical resolution of the ECM is resolving the situation better than gfs? I certainly wouldn't expect the gefs to necessarily see it and especially post day 8.

I also note note that over recent ECM ens runs, the attempt to split the vortex through n Greenland from the Alaskan ridge continually wavers as the ECM ens enter their low res post day 10.  

Im in not saying there is anything in that but whilst the high res ens keep the feature at day 10, I continue to wonder if it will be more of a player in the 10/15 day period than currently modelled.

rst