Alternate Model Discussion - into 2022

[knocker]

In the ext period the clusters tend to support the trend indicated by the mean anomalies of a weakening and retrogression of the Azore HP resulting in an Atlantic which is a tad more mobile

 

[phil nw.]

Just looking closer to home with height anomalies first for days 1-5 and then 6-10.The blocking high is never far away over the next 10 days and the Atlantic weather systems continue to be diverted mainly to the far north and away from W.Europe and the UK.

This means the largely dry weather will continue.The European precipitation chart for the next 10 days and the gefs graph for 2m temperatures and precipitation. 

 

Large areas almost bone dry with only the far nw of Scotland seeing anything more noticeable.A notable dry spell for January continues. 

 

[Uncertainty]

1 minute ago, knocker said:

In the ext period the clusters tend to support the trend indicated by the mean anomalies of a weakening and retrogression of the Azore HP resulting in an Atlantic which is a tad more mobile

 

The amplitude of the Atlantic ridge is a bit higher on the GEFS and there’s a bit more of a S euro low signal on the GEPS, but otherwise pretty good broad agreement.
 

 

The early breakdown on offer on the GEM and ECM Ops is not particularly well supported yet, but with solar activity ramping up quickly it wouldn’t be surprising.
 

Still not seeing a definitive way forward post the demise / relocation of the U.K. high…

[damianslaw]

20 minutes ago, Uncertainy said:

The amplitude of the Atlantic ridge is a bit higher on the GEFS and there’s a bit more of a S euro low signal on the GEPS, but otherwise pretty good broad agreement.
 

 

The early breakdown on offer on the GEM and ECM Ops is not particularly well supported yet, but with solar activity ramping up quickly it wouldn’t be surprising.
 

Still not seeing a definitive way forward post the demise / relocation of the U.K. high…

My thoughts are we will see a broadly westerly/north westerly pattern eventually, with heights sinking SW, but far enough west to allow Polar maritime shots raising prospect of something more wintry at least for the north - late Jan/early Feb.

[knocker]

The weakening band of rain associated with the cold front is currently over the north of England and will continue to track south through the day, finally clearing the south coast late this evening. Behind the front front clearer and cooler weather resulting in quite a widespread frost Sunday morning. And then once any fog patches have cleared a sunny day in most areas but with more cloud and some patchy rain/drizzle in the north

 

[knocker]

Further fronts track south east down the country late Tues through Weds before high pressure rebuilds from the west

[knocker]

The medium term anomalies are very amplified upstream with a strong westerly upper flow exiting the eastern seaboard across the Atlantic where it runs around the ever present high pressure in the east. There are still some differences on the orientation of this, ,  allied to the Euro trough, but generally we are looking at a pretty dry period over much of western europe

[knocker]

And in the ext period there is nothing in the clusters to contradict the impressions given by the means

[phil nw.]

A gif showing the the movement of the different air masses around the blocking high for the next 10 days as per the 12z gfs mean output.

 

The UK on the edge of the real cold feed mostly.Much of it going over the top of the block and into Scandinavia/e.Europe but we can expect a quick swipe of cold off a mid-week northerly before the high moves across again.

[knocker]

After another frosty and foggy start, most of England and Wales will enjoy another sunny day tomorrow but approaching fronts will bring cloud/rain to the NW during the afternoon and these will track south east overnight and through Weds, tending to weaken as they reach the retreating high ptessure. Some wintry showers over northern Scotland in their wake and perhaps down eastern coastal regions

And once the fronts are out of the way high pressure will rebuild from the west over the rest of the week and through the weekend

[johnholmes]

sums it up nicely k-thanks

[phil nw.]

Looking at the following week 500hPa ens mean pattern NH view for both GFS and ECM at day 10.

Differences in the placement of the high.

GFS showing it over the UK and the ECM sinking further south.A flatter looking Atlantic jet on the ECM and along with the more southern location of high pressure would suggest much of the UK would come under a more westerly Atlantic flow with less chance of any inversion cold even further south.

[mushymanrob]

Pinched these off Dr Simon Lees site

Its not looking good for snow/cold lovers..

 

[knocker]

Still very amplified upstream with the west North American ridge/tpv lobe trough  and a strong westerly upper flow exiting the eastern seaboard. But some variation downstream, albeit the high pressure remaining in charge, with the ecm perhaps indicating some linkage to the Urals ridge. Fore by all of that still looking very dry over western Europe with any rainfall concentrated in the north

[knocker]

Upstream the axis of the tpv has shifted a tad east, courtesy of the west North American ridge amplifying NE, but with no apparent impact downstream where the high pressure continues to hold sway.

[knocker]

Extending the ridge north east above the cut off upper low can produce some very cold temps in southern/central Europe

Edited January 18, 2022 by knocker

[knocker]

The alignment of the tpv with one lobe over the eastern Arctic does facilitate ridging in western Russia and possible linkage to the Azores HP north of the cut off upper low over the Eastern Mediterranean. Well-illustrated by this evening’s ecm. The correct pattern alignment could well advect colder air into southern/central Europe. But the clusters do not support the linkage scenario

[phil nw.]

A brief brush of Arctic air through Weds into Thurs. before the high returns and again settles over England and Wales by Friday.

Probably snow showers over N.Scotland and maybe some wintry flurries for a short while near eastern coasts before the northerly is cut off as pressure rises from the west and backs the winds off the Atlantic around the top of the high.

more night frosts are likely under the high as we head through the weekend with continuing dry conditions for many.

Sunday

The westerly breeze further north will keep things milder with nw Scotland seeing some light rain/drizzle over the weekend.

Edited January 18, 2022 by phil nw.

[phil nw.]

Looking at the 5 day ens mean ht and 850's anoms for days 6-10 

We see the high clinging on manfully over the south of the UK but i suggest coming under increasing  pressure from the jet running across the north into Scandinavia.An upper cold pool bringing bitter weather is expected over E.Europe extending quite a way south.

Edited January 18, 2022 by phil nw.

[knocker]

Some patchy rain associated with a cold frront across the north at the momemt and this will track south through the day followed by cooler air with snow showers over Scotland. And then this evening and overnight another cold front tracks south and in its wake snow showers down to quite low levels in the north and showers also along the eastern fringes in the now brisk northerly, some possibly of sleet snow. Once the font clears Thursday a sunny but cold day after a widespead frost with temps below average

and then through the rest of the week and the beginning of next high pressure again becoming influential and thus the return of frosty/foggy mornings, particularly over England/Wales, with the usual caverats regarding the northern periphery of the HP

[knocker]

In the ext period the mean anomalies still not agreeing on the alignment of the tpv and thus the amplification. if any, of the subtropical high in mid Atlantic. But as an overview a relaxing of any amplification with a strong westerly upper flow running towards low pressure in south east Europe. Temps around average

Edited January 19, 2022 by knocker

[knocker]

Nothing constructive to add regarding the medium term anomalies this evening so just a glance at how the ridge alignment/cut off upper low is affecting the European surface temp distribution

Edited January 19, 2022 by knocker

[phil nw.]

The gefs Europe view of upper and surface expected temperatures over the next few days

Colder at the surface under the high with the inversion over  parts of England and Wales. 

[knocker]

Strat/Trop connecting?

 

Edited January 20, 2022 by knocker

[Gowon]

11 minutes ago, knocker said:

Strat/Trop connecting?

 

Does that mean a stronger vortex with those two connecting?