Model output discussion 10/02/21

[minus10]

Must admit the gfs12z is a strange one. Coolish easterly from around 17th to end of run. Although more likely statistically I always feel it is not a particularly good thing to have at this time of year, although in any sunnier spells could feel reasonably pleasant. Also the ever present threat of cold air again to the NE in the latter stages. Although FI it keeps appearing.....

[MATTWOLVES 3]

I'm not sure this Winter is quite done with us yet folks...I've got this nagging feeling we could yet see something quite potent before it finally packs its bags...this is also true for the USA where potential is there also going on Judah latest thoughts.

ECM finishes with cold air brushing the SE quarter...but let's be honest,its not going to take too much correction Northwards of that High to bring us much colder air more widespread! The GEM quite frankly is a gem.

Come on guys and gals...join me in that final chase...one for the road so to speak! I'm thinking @Mike Pooleas is Summer head on now I can sense it Mike and @Allseasons-si I feel as still that feeling of unfinished Winter business in him..you love it Si.. I think @Griff and @Don have retired from the thread...where the hell are you guys! 

 

 

 

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Edited March 9, 2021 by MATTWOLVES

[Tim Bland]

ECM keeps us under the high and sends the cold easterly through France on this run 

[stodge]

Evening all

Thought I would take a night off from model watching. More than a hint of spring in lowland East London today but the quickening breeze this evening a harbinger of a more unsettled spell starting tomorrow and lasting, well, 3-5 days at least. Beyond that, a return of heights from the south west for mid moth and just beyond but the position and orientation of said heights a long way from resolution (well it was two nights ago).

Has an additional 48 hours provided clarity? Let's see.

T+144 and T+240 charts first from GEM, ECM, GFS OP and GFS Parallel:

T+144 (March 15th):

T+240 (March 19th): 

A broad divide between the American models and the Europeans/Canadians (as we often see). The GFS OP and Parallel are quicker at clearing the trough east over Scandinavia and building the ridge from the south west towards Scandinavia. From there, ECM and GFS OP and Parallel all end up in the same place with the sore of heights close to or just to the east of the British Isles. There's a light E'ly flow for southern England but calm conditions elsewhere. However, GEM goes very much its own way building heights to Greenland and bringing a cold NE'ly flow by T+240 with -8 uppers for northern and eastern Britain which would be a real wintry feel. It's never wise to wholly discount GEM and it'll be interesting to see if this evolution is an outlier in the coming days.

Moving on to the latter third of month and the approach to Easter, the T+312 and T+384 charts from GFS OP, Parallel, Control and CFS:

T+312 (March 22nd):

T+384 (March 25th):

Certainly plenty of interest in far FI tonight with all three GFS perturbations raising strong heights close to Greenland and while OP keeps an ESE'ly, it's a straight line N'ly for Parallel and a nice cold trough on Control. CFS goes its own way keeping the Atlantic in charge but GFS is clearly sniffing something (aren't we all) as far as the latter part of the month is concerned and those hoping for a straight line progression into spring may be disappointed.  Could we be looking at even more delayed impacts from January's SSW or is this a trop-led development? Either way, it keeps plenty of interest for the days to come.

[Frosty.]

That’s a really stunning GEM 12z day 10 chart for any coldies that are still around, and looking through the ensembles there’s a few cold members and even towards the end of March too..I also noted there’s a mention of cold on today’s update towards the end of March into early April..although the word fleeting was also used...anyway...we can’t completely rule out another outbreak or two of wintry weather until it becomes an impossibility!  

 

[Mike Poole]

ECM mean T168 and T240:

It is pretty much as we are expecting, folks, with uptick of AAM forecast:

I’d be fairly confident of settled conditions going into spring proper, and tentative expectations that it might extend toward summer, will be really interested to see the GloSea5 output in the next few days, but I think it should be supportive of a fairly decent summer...

And @MATTWOLVES I’m certainly not averse to another wintry blast but have my summer head on now

 

Edited March 9, 2021 by Mike Poole

[stodge]

10 minutes ago, Mike Poole said:

It is pretty much as we are expecting, folks, with uptick of AAM forecast:

I’d be fairly confident of settled conditions going into spring proper, and tentative expectations that it might extend toward summer, will be really interested to see the GloSea5 output in the next few days, but I think it should be supportive of a fairly decent summer...

I think it's far too early to be calling summer - we've had a number of decent spring spells (last year being one) but these don't always translate into settled summer conditions. We know northern blocking can be a feature of the late spring evolution right up to the Buchan cold spell in early May. The Scandinavian HP can deliver in May but it's not much cop for eastern coastal counties if the sea temperatures are still low - it's the ideal time to visit the Hebrides I'm told.

[Singularity]

Next week has the look of an overestimated cutback of the polar jet to me... but we’ll see. Such easterlies, occurring during a +AO, are entirely reliant on that cutback for the cold feed to affect the UK much.

We've often seen them toned down nearer the time, placing us right under our own HP cell or even an extension from the Azores instead. I imagine many on here would prefer that outcome now, as opposed to the other one a month ago!

[Allseasons-Si]

Thanks @MATTWOLVES& @Jon Snow(Karl) for the post's ^^ and yes it wouldn't take much of a shift in that hp cell a bit further N/NW

the ECM mean at day ten 500mb and upper 850's shows a cut back into the SE of the uk with a Genoa low and winds from the NE quadrant so a cool high with it being situated/placed to our W/SW and for the milder crew you need this hp cell to the E/SE to draw warmer air from the S/SW

like i mentioned in my previous post/s there is still some resolving with this hp cell yet,...place ya bets

looking at the trajectories/tactile,..it looks like this hp cell is starting to push N/NW of the UK by 192...

And finally the EPS at day ten shows plenty of Atlantic ridging/blocking,...cluster 1,2,3

tentative signs there and we may get one last shot at a cold snap/spell before,...erm,...springs out

 

 

Edited March 9, 2021 by Allseasons-si

[Mike Poole]

2 minutes ago, stodge said:

I think it's far too early to be calling summer - we've had a number of decent spring spells (last year being one) but these don't always translate into settled summer conditions. We know northern blocking can be a feature of the late spring evolution right up to the Buchan cold spell in early May. The Scandinavian HP can deliver in May but it's not much cop for eastern coastal counties if the sea temperatures are still low - it's the ideal time to visit the Hebrides I'm told.

I’m not calling summer!  At the moment I’m looking at patterns that might be self reinforcing, either with the jet or with SSTs.  They may come to something or nothing, we will see...

[damianslaw]

Lively weather in the next 48 hours, gales, something we haven't had to mention much this winter season. Thereafter a cold showery airstream will quickly give way to high pressure again, hopefully a sunnier high than the recent one.. cold nights and sunny milder days. 

As we move deeper into the month, signs heights may eventually ridge west with a scandi trough cut back, I can see why the models are showing a retrogressive pattern which would lead the trail to a colder spell. 

Keep an eye on heights to our south, lowering heights here will prevent the high from sinking SE with the jet then riding over and round the high.

[Daniel*]

The mild weather next week has been downgraded somewhat, dry conditions still expected to return. 

[ANYWEATHER]

After a Stormy night Wednesday night going into Thursday morning , for the southern half of the Uk things look intersting to give a very unstable Polar Maritime airmass across the Uk . Thunder Snow won't be ruled out in Western regions . As we move into late weekend another big change......!!!

[Allseasons-Si]

Am i still in winter mode,..of course i am...

spare a thought from the gfs at just 144 hrs out as it's more amplified than the 12z...

18z 144 v's 12z 150

the gfs//p is also more amplified than the 12z too

18z 138 v's 12z 144...

like i said,..i wouldn't mind one last blast of cold,...but please i would love a nice warm spring going into summer with some cracking thunderstorms,...i would chase both to the end

C'mon guys,...where are you all,stay with the cold crew for just a bit longer

Edited March 9, 2021 by Allseasons-si

[minus10]

Now the 18z gfs is introducing cold air from the N N/W, again in FI though. Is it going to be a cold end to March?..

[Gowon]

Anybody else having trouble getting on meteociel?

[mb018538]

Starting to get some ideas now about the change to more settled weather - and also a trend to 'west is best' as it would appear the high is likely to sit just out to the west of the UK. Net result is milder air flowing up the western half of the UK, and colder air toppling down the eastern half around the high, as roughly shown by GFS/ECM/GEM:




 

[Jordan S]

Morning

One more look at the approaching low pressure system for tonight bringing quite a stormy night for some.

GFS..

GEM..

The wind on the southern side of the storm gradually weakening which my post on sunday mentioned as it crosses the country, the strongest swathe of winds and the low pressure centre separate to an extent with what was the centre moving away to the north, the noticeable bend in the isobars below it possibly redeveloping into another closed circulation as it moves into the north sea tomorrow morning.

We have a very strong jetstream 150-175mph moving through England and Wales tonight.

Severe gales are likely to develop in parts of the irish sea with winds gusting to around 65-75mph.

quite stormy widely for England and Wales with gales for some..

The expected wind gusts haven't really changed since my post on Sunday morning winds reaching 50-60mph quite widely inland, but slightly more than this is possible for a few parts, particularly for Wales, the Midlands and east Anglia too where in these areas there is a reasonable chance of wind gusts upto around 65mph in a few inland areas for a time during the early hours of tomorrow morning where the isobars on the pressure chart are closest together.. for the mountains of Wales gusts may reach over 80mph.

During friday night and through saturday a low pressure system moving east or southeast bringing strong winds back into southern and southwestern England and Wales, gales may develop again around the coast and another area of rain some of it wintry possibly on high ground of central and northern areas.

Early next week high pressure moving north to the southwest of the uk into especially western parts of England and Wales bringing settled mostly dry weather after monday. It is also now likely to become drier and more settled for Scotland and northern Ireland too, winds lighter with little rain here.

A change though in the temperatures through the first half of the week with the week likely starting off quite cold at first before the high pressure system moves more over the top of the country quite likely to become milder for Scotland and northern Ireland but colder conditions likely further southeast with frosts.

 

Edited March 10, 2021 by jordan smith

[johnholmes]

Wed 11 th and update on 500 anomaly outputs

Ec-gfs and a similar pattern to the past 24 hours, marked troughing down e’ern n American seaboard into atlantic with marked ridging e of this to ne of Greenland over n Scandinavia/Russia, marked meridional pattern for the eastern half of the chart, some signal for similar in far out over pacific

Noaa 6-10 and it is very different from 24 hours ago. It has now joined ec-gfs in a similar pattern for a similar area with quite marked meridional flow, complete with trough into w’ern Europe. It also shows a marked trough off s’ern Alaska with ridging w of this.

The switch on noaa 6-10 to ec-gfs is really marked in a 24 hour period, never used to happen but it does now and then with ec-gfs taking the lead. It still needs a couple more days to give real confidence though. The 8-14 is very close as well.

ECMWF/GFS DAY 8-10 MEAN 500MB HEIGHT COMPARISON

WWW.METEO.PSU.EDU

Climate Prediction Center - 6-10 Day 500mb Outlook

WWW.CPC.NCEP.NOAA.GOV

 

[Singularity]

 

ECM left, UKMO right. The latter shows the sort of correction we usually see in these situations; less of a cutback of the polar jet around the eastern flank of the high.

The difference is already significant at +120, so it's a classic flatter UKMO situation at hand. Last month I'd have frowned at it, this month I'm beckoning with open arms as I really don't enjoy cold spells in the 2nd half of March down here - it usually means a nagging wind with any snow being non-settling or very short-lived on the ground.

The flatness of the ridge has big ramifications going forward. Without the polar jet cutback, warm air can be thrown across from the east to initiate a fine, warm spell of weather. Conversely, with the cutback in place, even a southwest-northeast transport of the warm air only serves to elongate the high northeast from the UK for a time, dragging in more cold air such as the 00z GFS depicts.

[feb1991blizzard]

Meteociel has burnt down so it may be a while yet before its back up.

[SqueakheartLW]

8 minutes ago, feb1991blizzard said:

Meteociel has burnt down so it may be a while yet before its back up.

Meteociel got so much demand during the winter with all those cold charts that were showing and couldn't handle the demand. Anyway we still have wetterzentrale to look at

Here are the two mildest/warmest daytime options from the 00z GFS

Both of these have temperatures around 16C with dry, warm and sunny weather under high pressure

Here are the 00z GEM mildest/warmest options

Another selection with temperatures around 16C again but generally less anticyclonic than the GFS is

Time for the coldest options in the 00z GFS

Two very different patterns that both produce daytime maxes around 3C. A cold cyclonic westerly option and a more typical cold easterly option showing up here

Finally the two coldest 00z GEM options

Two very different cold options, just like with GFS. The first is cold and anticyclonic, the second is more of a cold northerly flow with a risk of snow showers. Both have temperatures between 3 and 4C

[feb1991blizzard]

4 minutes ago, SqueakheartLW said:

Meteociel got so much demand during the winter with all those cold charts that were showing and couldn't handle the demand. Anyway we still have wetterzentrale to look at

Here are the two mildest/warmest daytime options from the 00z GFS

 

 

 

 

An

 

 

 

 

 

T

Its a fire i think where their servers are and some are now unusable.

[Daniel*]

Spring warmth? More like a spring chill...

[Summer Sun]

2 hours ago, feb1991blizzard said:

Meteociel has burnt down so it may be a while yet before its back up.

Major fire at the OVHcloud network in Strasbourg