Model Output Discussion - heading into April

[Mike Poole]

ECM ensemble mean for 12z, T168 and T240:

 

Supportive of the Azores ridge scenario, that is all I need for now, details will be firmed up in subsequent runs....

[damianslaw]

53 minutes ago, mb018538 said:

It’s time time of year when you want to see that Icelandic/Greenland/NE Canada low set up. We had it all winter which ruined any chances of cold weather....but it can be our friend in the summer!

Good for the SE quarter of the country, but poor for the NW, as fronts move in from the atlantic with associated cloudy damp gunk, petering out by the time they reach the SE, but as you say its the standard typical summer pattern, especially during second half. 

In the reliable, a block holding sway to our west, UK locked on the cold side of the jet, dry with some sunny spells, gradually warming up to average levels.

Eventual pattern is most likely the ridge toppling through the UK, with the azores high ridging NE at the same time, to bring in some warmer conditions, before the atlantic makes an attack possibly a southerly unstable draw as it does so. ECM shows this scenario, very plausible. 

[carinthian]

19 minutes ago, Mike Poole said:

Hi @carinthian Government probably going to rain on that parade.   I’ve been drinking beer in the sun in my flats’ car park, that has had to do unfortunately.  But agree, summer weather prospects for UK looking decent.  Stay safe!

Still too chilly here @Mike Poole to drink beer outside . Snow patches lingering in the garden. Just want warmth now at this time of year . Will be a bit of a shock tomorrow and into Monday , especially over England and Wales with that cold blast. Not sure it will get as far as the Eastern Alps but snow is still forecast for a time on Tuesday. We will see.  Looking at sunshine totals over much of the kingdom , you lot are doing very well. Hope it continues and ECM run verifies for a return of warmth. 

C

Edited May 9, 2020 by carinthian

[Singularity]

It’s interesting to see the potential for the Atlantic trough to dictate the direction of travel from a position S of Greenland again later next week.

Reason being, that’s what’s encouraged by one of the only two driving forces pointing toward a warm and dry type summer for 2020 - the N Atlantic SST anomaly pattern.

Research has shown that what we have in May tends to persist through the summer via positive feedbacks involving the atmosphere. Anomalous warmth east of Newfoundland enhances the temp gradient S of Greenland, encouraging cyclogenesis there I.e. a +NAO.

 

The other factor isn’t actually with us yet - a negative Indian Ocean Dipole (as forecast by BOM). Analogues for this are anomalously settled for S UK, most notably in Jul-Aug. Not so good in the north mind - a lot of changeable westerlies. Heat tending to build up from the south at times, though.

[Mr Frost]

Tell you what if you live down South (Far South as the day goes on) tomorrow is looking well decent - could be a 20C around lunchtime! (Cold air arrives late afternoon/evening) 

 

Now onto the Arctic...plume! 

Monday, Tuesday, Wednesday, Thursday and Friday (takes us up to 15/05/2020)...if you like temperatures below average during daytime and chilly nights this coming week is for you!  (At least it will be mainly dry for most with some sunshine - plus you can maybe add a degree or two onto those values ...still crap though!)

Pretty boring stuff really but everyone has their own weather preference so I am sure someone will be loving it! 

 

So to sum up the above...

Not quite the weather I was hoping for in mid May but really can’t complain after a glorious warm/sunny Spring so far.

Edited May 9, 2020 by Mr Frost

[Don]

36 minutes ago, Mr Frost said:

Tell you what if you live down South (Far South as the day goes on) tomorrow is looking well decent - could be a 20C around lunchtime! (Cold air arrives late afternoon/evening) 

Yep, looking like the far south will squeeze out another decent day before things turn much colder in time for the new week!

[Mapantz]

2 minutes ago, Don said:

Yep, looking like the far south will squeeze out another decent day before things turn much colder in time for the new week!

It's looking rather cloudy down here.

Very windy too, by lunchtime.

[Methuselah]

Good morning peeps.

Well, hopefully (and so long as the bog-end of the GFS 00Z is in the right ballpark) the tPV looks to be taking its last breath...?

    

And the GEFS 00Z temperature ensembles are nae bad either!

    

But, there are still a few rounds of Snakes & Ladders to go, before we finally get there?

[Djdazzle]

ECM 0z is another lovely run after the initial cooler blip. Very consistent with yesterday’s 12z.

[Singularity]

Encouraging that even GFS, with its ‘lockdown’ of the low over Scandinavia (which other models allow to depart to the northwest), brings a lot of high pressure our way with some pleasant temps by next weekend (when allowing for the usual too-low temp bias).

ECM works out stupendously well... might be an ‘ideal world’ run but we’ll see. UKMO looks supportive of the direction of travel as of +144 .

[damianslaw]

11 hours ago, Singularity said:

It’s interesting to see the potential for the Atlantic trough to dictate the direction of travel from a position S of Greenland again later next week.

Reason being, that’s what’s encouraged by one of the only two driving forces pointing toward a warm and dry type summer for 2020 - the N Atlantic SST anomaly pattern.

Research has shown that what we have in May tends to persist through the summer via positive feedbacks involving the atmosphere. Anomalous warmth east of Newfoundland enhances the temp gradient S of Greenland, encouraging cyclogenesis there I.e. a +NAO.

 

The other factor isn’t actually with us yet - a negative Indian Ocean Dipole (as forecast by BOM). Analogues for this are anomalously settled for S UK, most notably in Jul-Aug. Not so good in the north mind - a lot of changeable westerlies. Heat tending to build up from the south at times, though.

That suggests a very typical summer pattern developing, azores high ridging through, jet to the north on a SW-NE trajectory, rain and westerlies in the north, drier and warmer in the south. However, so far May is not showing this pattern and the immediate outlook is a blocked one, perhaps we may see more of a NW flow with mid atlantic heights, fronts attacking the north and west - south drier with the ridge building in more, this would tie in more with La Nina conditions.

Back to the here and now, cold polar air invading the UK, cold frosty night ahead, staying chilly through next week, heights only slowly cutting off the cold source.

[SLEETY]

Gfs and ecm miles apart in the longer term ,but they and UKMO  both underestimated the Northerly in the shorter term,with another pool of very cold air hitting Scotland again mid-week.

• So anything is a possibility going forward.Im going for cold weather to persist throughout  May,and not  because I went for a cold CET for May or anything 

[Djdazzle]

Overall, I think the intensity of the initial northerly was overdone, with very low uppers across most of the country. We were meant to be under quite a strong N / NE flow  for quite a few days with LP not too far from the E. Gradually, it’s been moderated to more of a NE drift after the initial blast as HP builds from the west.

Of course, there is a chance that chilly conditions persist for longer, but even the GFS is moving away from this scenario.

Edited May 10, 2020 by Djdazzle

[Scorcher]

37 minutes ago, SLEETY said:

Gfs and ecm miles apart in the longer term ,but they and UKMO  both underestimated the Northerly in the shorter term,with another pool of very cold air hitting Scotland again mid-week.

• So anything is a possibility going forward.Im going for cold weather to persist throughout  May,and not  because I went for a cold CET for May or anything 

I don't think they did underestimate it- the opposite if anything in terms of intensity. The progress of the cold air southwards has also been a lot slower than initially modelled.

[Frosty.]

WOW just catching up!..what a fabulous end to the ECM 0z operational..fingers crossed!

 

[Djdazzle]

GFS 6z continues the improvement.

[weathermadbarnsleylad]

Yes the trend now from ecm/UKMO but not gfs/but 6z is better. High pressure building up from SW by the weekend. Starting of low teens but temps building nicely by early next. The trend is my friend. 

[Zak M]

Not bad from the GFS 06z!

   

[SLEETY]

Wish it was winter type charts showing up consistently now on gfs.Look at that blocking over NE Europe.Could be a hot summer if it comes to fruition,as the continent is warming up nicely.

 

Edited May 10, 2020 by SLEETY

[Methuselah]

I think I'd take that, in late May: the T850 0C isotherm is a long, long way off!

    

[mb018538]

ECM 00z clusters are also very promising. At day 10, high pressure building in (strength to be determined) is very much favoured. The rip-snorting spring weather to resume after a little break early this week?

 

[Man With Beard]

19 minutes ago, mb018538 said:

ECM 00z clusters are also very promising. At day 10, high pressure building in (strength to be determined) is very much favoured. The rip-snorting spring weather to resume after a little break early this week?

 

Guessing we'll be seeing temperatures north of 25C if that comes off - which looks highly likely. 

[tight isobar]

@AZHP..

The Azores pressure points are open and alive as we gain.

And still every possibility of corrections for PLUME type sceanarios later on. The human inputs =@fax from Thursday *although* short in time scale also catching the eye for further progressive infer of a HP domination last 3rd of may!!!

The best are just from where the draw ends up *atm*..in regards to pressure points alignment for glory=plume work...or 2nd prize of a somewhere allocated Azores link or persuasion.

The London ens for me slow in clasping -the transfer after our current overhead changes @arctic based air....

but with the transfer comes largely dominated hp mass cells throughout...so warmer =more settled a certainty...@day 5 plus...yet as AGAIN..with more than amicable scope for more noteworthy latter on...@heat @warmth....the faxes will be of interest..over the next 5=7days....

 

enjoy your Sunday...

[Daniel*]

Good signs of a real warm up day 8-10 quite a spread in MSLP though, maybe indicative of solutions with ridge being centred further NE rather than SW, that will be critical for us southerners could be less settled, we could do with rain the ground is parched. The much more unsettled weather isn’t that far to south, last night parts of Paris had 60mm in the space of 3 hours. Spain also experiencing very unsettled conditions this year, last month Barcelona had more than 400% of their average rainfall if I remember right. 

[Frosty.]

I gotta say I’m loving the GEFS 6z mean since it shows high pressure (blocking) being the dominant feature, no sign of Atlantic mobility at all, it looks GREAT...sure there will be a few ripples in the water along the way but I have a good feeling about the remainder of spring and I’m positive about early summer too!
 

 

 

 

Edited May 10, 2020 by JON SNOW