Model output discussion 9th April onwards

[Frosty.]

I don’t think the ECM 12z operational is garbage, well it is for a while but it then improves..looking at the bigger picture (NH)...I would keep an eye on that very warm air to the south, it does start moving our way..of course, it’s T+240 plus hours range but still worth discussing?   

 

Edited May 20, 2021 by Jon Snow

[Howie]

I'm starting to get concerned that the upper trough thing will be a reality and we'll just get cool, cloudy weather. Just our luck......

[Cheshire Freeze]

18 minutes ago, mb018538 said:

Sorry but that 12z ECM run is utter garbage. Not only do we have a pesky upper trough left from the Low over the UK in the first half of the week, another nuisance feature makes its way in from the west. At day 9 we have 2 upper lows visible. Net result is cool air aloft, plenty of cloud, some showers and disappointing temperatures despite pressure being high. Hoping it’s wrong and GEM is more on the money.

It’s because as we get closer, the HP is being shown to gain more latitude...Something that I have pointed out but which has largely been ignored.

It’s something we’ve been seeing happen for months. Still, can’t see it being as crud as it is right now and it’ll certainly warm up some.

Edited May 20, 2021 by CreweCold

[Uncertainty]

On 17/05/2021 at 20:41, Uncertainy said:

Are we finally heading towards a drier, perhaps even warmer spell of weather?

We’ve had a number of false dawns in the modelling, especially in the day 8+ range wherein recently the modelling has been utterly abysmal...

Here’s last Friday’s ECM effort at 192

A major ridge building in the wake of this week’s low

Now today’s 120

The ridge merely a stopgap before the next major unseasonable low barrels in.

The GEFS as ever, have been particularly guilty of signposting a U.K. high when In reality the true signal was a U.K low. 

So how can we trust that there is a real pattern change on the way?

Well, you’ve got to look for consistency across models and runs + supportive background signals. Recent phantom Pressure rises were not supported across all models. Earlier in May the tropics, stuck around the Indian Ocean, were not supportive of U.K. heights either.

Here’s the neutral enso phase 3 composite for May:

 

But now we have a much more consistent signal for heights near the U.K. and drier, perhaps even relatively warmer weather:

ECM day 10

GEM day 10

GFS day 10

Beyond this, the EC clusters very supportive of HP near the U.K. 

Some warm, some cool, the vast majority of members would be dry.

The GEFS in broad agreement.

Even the lesser models are in agreement vis U.K. heights...

Nasa

 

JMA

 

CMA

The last piece of the puzzle is consistency, at this range plenty of things can go wrong. The pattern change still isn’t really in range of the UKMO. If the charts above stick around for another 48hrs then we can start looking at the orientation and longevity of the high. For now, it’s mere existence is still questionable so we watch and wait as ever.

Josh

Well 2 days later and where are we now?

The amplification delineated above is still very much evident, but the details are far from resolved. So much so that the GFS in its wisdom has manifested a real ‘worst case scenario’, wherein a trough gets trapped underneath the amplifying ridge and just slowly fills across the U.K whilst pressure builds strongly to the North.

Make no mistake this would be a rotten and dismal solution but it is by no means impossible.

The ECM has sort of hinted at various other manifestations of this breakaway trough, here’s yesterday’s 0z

These Ops showing this evolution  have generally ‘gotten away with it’ in terms of maintaining high pressure over the U.K. but the 12z gfs today shows the deal isn’t quite done on next weekend just yet.

 

The latest ECM does hint at this same perturbation, but the fledgling trough dissolves under the strength of the ridge over the U.K. plus the ridging AH and thus a dry, sunny (esp in the N and W) if still somewhat chilly weekend beckons

A closer inspection of the EPS spreads highlights the potential track of this disturbance. The blue colours across SW U.K. suggest a significant cluster of members showed this feature.

The GEM holds the shortwave to the western edge of the ridge then reabsorbs it into the long wave trough ensuring it never comes within 500 miles of the U.K. 

Whilst this solution ends very pleasantly the downstream trough maintains its influence over Eastern parts in particular until the latter stages of the run.

Summary: 

- Still looking highly likely for HP to build near/through/just west of the U.K. but until the track of this disturbance is cleared up the threat of a green snot GFS drossfest remains...

- No clear signs of anything particularly warm yet. We’ve gone whole winter months without getting the -5isotherm anywhere near the U.K. and look at this day 9 ECM effort on the 29th of May!

- Finally, a sneak peak at the end of May SST anomalies in the Atlantic...

 

More WCW tripole than not? Not a horseshoe and hard to tell with these coral bleaching charts but I’d say we haven’t seen the back of Greenland blocking this year and with -EQBO coming and *possibly a resurgent Nina come fall then, well, it might at least settle the ‘teaser’ winter debate once and for all!

Josh

[Djdazzle]

Models seem determined to scupper any chances to escape this dire pattern we are in. 
This is by far the worst May that I can remember. In fact, I don’t recall one being even half as bad as this.

But still confident of a major pattern change in early June.

[snowsummer]

Maybe that little feature that's formed somewhat early in the Atlantic may be our saviour in the not to distant future? Either that, or the weather will finally sort it's self out and that little feature will be the thing that knocks us back to square one!  ( Ignore me if I'm talking rubbish, far too much time, and wine, on my hands!!)

[Guest]

Feels like we’ve seen a big deterioration in the output in the last 24hrs, high pressure appears to have much less influence as we move through next week leaving the uk open to further spells of unsettled and cool conditions. It really is becoming the one worst spells of unsettled and below average conditions I can remember especially with that ECM long term outlook, could end up writing off Apr, May and June at this rate. 

[Roadrunner]

@Jon Snow I need some of your positivity this morning! Just need the first weekend in June to be dry and sunny in Bournemouth due to a golf weekend I'm going on. Give me some hope mate - please!! 

[mb018538]

41 minutes ago, Alderc said:

Feels like we’ve seen a big deterioration in the output in the last 24hrs, high pressure appears to have much less influence as we move through next week leaving the uk open to further spells of unsettled and cool conditions. It really is becoming the one worst spells of unsettled and below average conditions I can remember especially with that ECM long term outlook, could end up writing off Apr, May and June at this rate. 

Not sure I totally agree there - though I don't like the way the GFS evolves and ends up with this at the end. If northern blocking returns in full force then the chances of anything warm and settled lasting is pretty remote.




A bit at odds with the ECM at the moment though.

Look at the 00z 240 NH view against last nights ECM 12z mean. No high pressure over the pole at all on the ECM.



GEM is fairly pleasant by day 9/10, especially in your neck of the woods sheltered on the south coast. Light winds and temps high teens/20c by Monday there.

[mb018538]

ECM looking pretty good by day 9 too 

For those that like the sun and settled weather without the heat (and there are a few on NW!) then this could be ideal. Upper teens and light winds.
A nice tonic as I sit in my work office listening to 50mph winds rattle around the windows.

Edit - Day 10 also looks grand:



No northern blocking to be seen either:


 

Edited May 21, 2021 by mb018538

[Guest]

5 minutes ago, mb018538 said:

ECM looking pretty good by day 9 too 

For those that like the sun and settled weather without the heat (and there are a few on NW!) then this could be ideal. Upper teens and light winds.
A nice tonic as I sit in my work office listening to 50mph winds rattle around the windows.

ECM ends up pretty nice as you say at D9 & 10, really need to start getting these charts out of D9 & 10 which is where they've been for an eternity and get them into the reliable time frame. 

[Weather-history]

5 minutes ago, Alderc said:

ECM ends up pretty nice as you say at D9 & 10, really need to start getting these charts out of D9 & 10 which is where they've been for an eternity and get them into the reliable time frame. 

Cloud amounts don't look great for eastern areas though but it is a long way off

[mb018538]

9 minutes ago, Weather-history said:

Cloud amounts don't look great for eastern areas though but it is a long way off

Probably because there's a 1033mb low trapped in there over the weekend! 

A long way down the road though as you say. That'll be the fly in the ointment on this particular run, but very likely to change. 

[Guest]

8 minutes ago, mb018538 said:

Probably because there's a 1033mb low trapped in there over the weekend! 

A long way down the road though as you say. That'll be the fly in the ointment on this particular run, but very likely to change. 

That has to be the highest low I've ever seen! The way its going its almost certain to come off lol!! 

[Methuselah]

Everything still reminds me of May-June 1983. But, at least this morning's GEFS temperature ensembles hold some promise:

          

Edited May 21, 2021 by Ed Stone

[Methuselah]

That's it, I'm done! Time to head for the Greenland Riviera! 

     

[mb018538]

Looks like the 6z GFS is having another wobbly....I'll leave it to go on it's merry way.

Edited May 21, 2021 by mb018538

[mb018538]

00z vs 06z for Bank Holiday Monday - Greenland high vs Greenland low. Nice and consistent! 

[Frosty.]

30 minutes ago, Ed Stone said:

That's it, I'm done! Time to head for the Greenland Riviera! 

     

I hear the Greenland Riviera is lovely this time of year..hmmmm.. ..anyhoo,  the GEFS looks fine in early June further south!...thanks Roadrunner..good luck with your golf weekend.. ‍
 

 

Edited May 21, 2021 by Jon Snow

[Methuselah]

30 minutes ago, Jon Snow said:

I hear the Greenland Riviera is lovely this time of year..hmmmm.. ..anyhoo,  the GEFS looks fine in early June further south!...thanks Roadrunner..good luck with your golf weekend.. ‍
 

 

Time to issue a country-wide BOLO for some decent warmth?      

                                                                                                                                          

[Uncle_Barty]

In 25 years of keeping records, I have NEVER failed to reach 21c / 70f before the end of May.

That record definitely under threat this year.

[Frosty.]

5 minutes ago, Ed Stone said:

Time to issue a country-wide BOLO for some decent warmth?      

                                                                                                                                          

Nice one Ed, you’re one of my favourite posters.. ..anyhoo..I love this perturbation!!!!!!!!!  

[Snow Shoes]

48 minutes ago, Uncle_Barty said:

In 25 years of keeping records, I have NEVER failed to reach 21c / 70f before the end of May.

That record definitely under threat this year.

If and when we do get any warm weather this summer I'm guessing that the surrounding sea temperatures (currently 9-10c around much of Uk) might temper the effects of any warming fairly well inland (especially if winds are blowing from the North sea) 

[Frosty.]

Chin up guys, I don’t care if you like me or not!...the GEFS 6z shows some fine and warmer POTENTIAL...into early June!!! ...I can’t wait for the proper hot potential further into summer........there will be no stopping me then..unless Dr Evil stops me ??....,   

 

 

Edited May 21, 2021 by Jon Snow

[Methuselah]

Yes sirree, Bob, I do detect a smidge of potential: