Model Output Discussion - Early Summer and Beyond

[mushymanrob]

Theres no route to cold conditions on this chart which suggests (as expected) high pressure to our east will prevail (remember initially it was supposed to be shunted aside rapidly), right through the mid month period. To me, this chart suggests a rather ordinary, average pattern. Mild at times, average-ish others , not overly wet?

 

Edited June 1, 2022 by DiagonalRedLine

[johnholmes]

Update Monday 7 March for 500 mb anomaly charts

The ecmwf charts out to 10 days shows the ridge declining to allow a fairly strong surface wsw flow to develop into the uk with the ridge declining/edging east into European (n on 500 but further s on surface charts)

The ec=no chart out by 0929 so using chart from Sunday shows upper ridge ne of Alaska with trough to sw and strongish flow beneath them both into n America and continuing below the main upper trough centred ne Canada

Into the strong westerly over the atlantic, not now into the uk but turned well n to a sw flow beneath Iceland  with cut off low off Iberia and ridge shown se uk into s’ern Scandinavia with little flow over the uk itself; quite a change from runs shown several days ago

Noaa has one upper low off ne Russia with the normal main low ne Canada, beneath this a mainly w’ly flow from the far west turning n of w over n America then rounding the main trough over the eastern seaboard into a strong w’ly atlantic that decreases markedly as it comes east with the main trough having a secondary trough out of it shown, and for a couple of days, off and just over w’ern uk down into Iberia. The strong ridging way north is still shown, from n’ern Scandinavia out to jan meyen with the centre of +ve heights having shifted over the past 4-5 days from off the east of uk to well into ne Scandinavia/Russia. The reasonable –ve heights shown in the eastern atlantic several days ago are no longer there, with the main –ve heights out of the Canadian trough ese towards Iberia.

So changes have occurred in the 500 mb pattern projection over the past 48-96 hours. These have implications for what the surface weather may do over the uk.

Gone is any chance there may have been of a cold easterly flow at the surface (never higher than about 15% in my view) to be replaced by an upper trough just sw of the Br Isles with a not very strong sw flow for most at 500 mb, more s’ly at the surface.

A rather changeable weather pattern with rain or showers at times as surface features run along in the 500 mb pattern. No major disruption for either rain or wind in my view.

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

Since I started typing the EC chart for the 7 th has come out but a quick look suggests no major changes that affect the UK look likely.

[Cambrian]

Mid-March looking good for some gentle, quite pleasant spring weather according to the 0z ECM and GFS operational runs at day 10. 

 

0z GEM op has a different idea though, with some polar maritime air waiting in the wings over the Atlantic. 

 

But for all three, the same story of long periods of the winter since the solstice continues - the oscillation of the jet stream keeping it in a range between being too far north over the Atlantic to allow proper Arctic air into the mix for UK and Ireland, limiting us to bursts of polar maritime air; and at the same time too far south over the top of Scandinavia to allow formation of a proper Scandinavian block - the PV anchored to Greenland with any eastward transfer only transient, again strong enough to keep the Atlantic going over the top of Europe and tight enough to keep the cold air well north. 
ECM / GFS / GEM

  

A post-equinox northerly perhaps the only remaining route to anything cold to round off the season. 

[damianslaw]

Oh dear exceptionally quiet in here today, but perhaps not surprising given the outlook looks fairly standard late winter/early spring fayre. Atlantic gaining a foothold again wettest further north and west becoming mild as well. Not much else to say.

[lassie23]

9 minutes ago, damianslaw said:

Oh dear exceptionally quiet in here today, but perhaps not surprising given the outlook looks fairly standard late winter/early spring fayre. Atlantic gaining a foothold again wettest further north and west becoming mild as well. Not much else to say.

That is the nail in the coffin of the winter that never was

[Mariescb]

1 hour ago, damianslaw said:

Oh dear exceptionally quiet in here today, but perhaps not surprising given the outlook looks fairly standard late winter/early spring fayre. Atlantic gaining a foothold again wettest further north and west becoming mild as well. Not much else to say.

It's a shame that it goes so quiet- such knowledgeable people on here only seem interested in potential severe cold/extremes of weather. Seems a waste of expertise tbh

[Frosty.]

Anyone up for another easterly wild goose chase in late March?! … it will probably end up in Greece again …

 

[SqueakheartLW]

2 minutes ago, jon snow said:

Anyone up for another easterly wild goose chase in late March?! … it will probably end up in Greece again …

 

Maybe we should have our spot the first 20C day of the year chase.

That is more likely to verify than a potential easterly or northerly in the next few weeks at least

 

Here's my first 20C of the year on the GFS extended run for today

Thu March 31st
P18     850hpa temp 12.2C     2m temp 20.2C

A rather pleasant day for the end of March with all that early season warmth for those of us who just want this miserable excuse of a winter out of the way and something decent to arrive.

Also just for fun I have the biggest extreme differences between members of the extended run for the same day in April

Fri April 8th     Warmest extreme
P15     850hpa temp 13.0C     2m temp 20.3C

Another warm pleasant day for early April with quite widespread 20C+ temps over England and Wales in particular. In stark contrast to the option below.

Fri April 8th     Coldest extreme
P20     850hpa temp -11.3C     2m temp 3.5C

Shows how much variety we can have in April when we have charts like the first one with uppers of +13.0C and 2m temps of 20.3C. Compare this with the Arctic blast option here which has uppers of -11.3C and 2m temp maxes of only 3.5C

The coldie in me hopes P20 can at least verify so we can salvage something from what we have endured but at the same time we could do with P15 just to have a nice decent warm day or two as well.

[Frosty.]

Looking at the GEFS 12z mean into the last third of March, there is some support for high pressure in the vicinity of the u k by then, of course the position / orientation of any anticyclone would be crucial to how it would feel at the surface at this time of year but for sure there is hope that following quite an unsettled / changeable period, especially further n / nw..it could then become more settled, at least across southern u k? ️  

Edited March 7, 2022 by jon snow

[mountain shadow]

1 hour ago, Mariescb said:

It's a shame that it goes so quiet- such knowledgeable people on here only seem interested in potential 

 

Not much to comment on with bog standard weather though is there?

Wetter and windier in the NW, drier and calmer in the SE. That's 80% of a yearly forecast. 

[Cambrian]

It really can be the most dichotomous month - not only the lions and lambs, but even just in the next four days - frost and snow, sunshine and shirtsleeves. 

The last of the widespread frosts for a while from the 12z ECM op for tomorrow morning.

Scraping 2 degrees for a substantial part of southern and eastern Ireland on Wednesday afternoon, with a few centimetres of snow possible (ECM) from this little occluded feature captured on the fax, extending up into western Scotland. Big contrast with the 12 degrees in eastern areas.

  

Warming up a bit for all by Friday afternoon, double figures or near enough for most, and up to 16 degrees in Eastern England. Sledging in Cashel, shirtsleeves in Cambridge, and all in two days!

[damianslaw]

1 hour ago, Mariescb said:

It's a shame that it goes so quiet- such knowledgeable people on here only seem interested in potential severe cold/extremes of weather. Seems a waste of expertise tbh

March and September are cousins, both see a clearout of regular posters who venture into the thread in winter looking for snow and cold, and in summer looking for warmth and sunshine, they both return in mid April and mid October respectively.. late March/early April, late Sept/early October without seeing the stats probably quietest time in this particular thread and forum as a whole.

[damianslaw]

3 minutes ago, Cambrian said:

It really can be the most dichotomous month - not only the lions and lambs, but even just in the next four days - frost and snow, sunshine and shirtsleeves. 

The last of the widespread frosts for a while from the 12z ECM op for tomorrow morning.

Scraping 2 degrees for a substantial part of southern and eastern Ireland on Wednesday afternoon, with a few centimetres of snow possible (ECM) from this little occluded feature captured on the fax, extending up into western Scotland. Big contrast with the 12 degrees in eastern areas.

  

Warming up a bit for all by Friday afternoon, double figures or near enough for most, and up to 16 degrees in Eastern England. Sledging in Cashel, shirtsleeves in Cambridge, and all in two days!

I'll be surprised if any snow falls out of that front, uppers look too high, but would need to see thickness, dewpoint and lapse rate forecasts. Doesn't look a snow maker only on highest ground.

[minus10]

Owhl no.......

[MP-R]

21 minutes ago, minus10 said:

Owhl no.......

Story of the winter. Always two weeks away...

[SLEETY]

Big Easterly setting up on gfs, would take it as it be mainly dry and as always probably too late for anything very wintry 

[SLEETY]

Turning drier after this weekend and lots of cold air around, but of course the UK avoids it all!! 

[minus10]

Very spring like on ecm 0z at 10 days with even warmer air potential if synoptics stayed favourable...

[mushymanrob]

That Polar Vortex is STILL over Baffin... crikey, thats a long time - all year so far!

But these charts do support, broadly at least, imho, the ops suggesting a warmer drier springlike pattern emerging.

 

 

Edited March 8, 2022 by mushymanrob

[Eagle Eye]

Initially, we have that low splitting on the turn in the jet that helps in building new low's in blocking. Not much to say about the low other than the fact that it will be blocked when stuck over and just off NW Spain because the turning point of the jet stream will be cut off and will either cross northwards or southwards of the low depending on where the low is. Either way the low will be blocked, the result will be different however. Clearly, the push from the other turning point out in the Atlantic is stronger on the western side and so the potential for a split is to move the eastern side downwards. If it were to do that it would initially weaken but something will happen that we see later as it moves onto the southern side of the low turning point that is what I think will, essentially, kickstart Spring.

Then we have the split that I was talking about, the low does strengthen (I think technically it's called deepening) when the jet stream flattens out and it can strengthen when sitting in that blocking. The high anomaly over NE Europe also goes as it is cut off but that doesn't look like it'll affect us because of our westerlies.

Finally, as the low is cut off, so is the jet to our south and that'll weaken with nothing pushing it and the Atlantic looks to be moving to our north and we'll have some blocking by the looks of it. With this, we have a continuing of our blocking and Atlantic jet (some may come further south and over us later but that will be too far in Spring and may only help to warm us up)but really the first in Spring and so this is what I think will , in a way, kickstart Spring weather. There's no way to know if they'll be changes in the future at my level of understanding but I do think this Atlantic jet will stay for a while and we'll have similar set-ups through Spring (mainly because I want there to be) and in the end, may bring some plumes and convective thunderstorm set-ups. This is slightly more hope casting since I'm going so far into the future and I want that to happen but with how Winter went, I see no reason for this pattern not to continue, at least in the short term.

 

  

[summer blizzard]

Euro still builds pressure to the south east around day 7.

[minus10]

It seems that the gfs charts are so nothingness that even net weather are not showing them now even though the 12z run is complete ( or is it just me?)

[Dorsetbred]

16 minutes ago, minus10 said:

It seems that the gfs charts are so nothingness that even net weather are not showing them now even though the 12z run is complete ( or is it just me?)

Maybe GFS has finally given up on this "winter"...

[ANYWEATHER]

1 hour ago, minus10 said:

It seems that the gfs charts are so nothingness that even net weather are not showing them now even though the 12z run is complete ( or is it just me?)

Yes the gfs 12z run is  incomplete ,not bothered about reporting it as the Predicted synoptics are enough to make you go to sleep

[Scott Ingham]

Edit

Edited March 8, 2022 by Scott Ingham
Wrong thread!