Model Output Discussion - heading into April

[Djdazzle]

4 minutes ago, SqueakheartLW said:

The biggest effect will most likely play out in Winter 2020/2021.

Winter 2016/2017 was a blocked winter and if the EQBO had played out as it should have done it could have been a cold winter. As it happened it could have been the continuing WQBO that put paid to it as we were close at times to pulling in sustained cold spells but the blocking always set up in the wrong place and put us in the mild area instead

This year we appear to be forming a tripole in the N Atlantic right now and with the prospect of a La Nina too which also looks to be forming right now combined with low solar activity then things looked to be shaping up quite well for a cold UK winter as the EQBO should have been at its strongest by the time we got to the end of this year but with the latest developments it looks like that factor could play against us getting a cold winter. Combine that with the warming N Pacific again then a more standard or mild winter now looks more likely again.

As for summer 2020 the rapidly forming La Nina is a bigger concern if you want a dry summer as previous summers where we have quickly transitioned into La Nina the weather has taken a dive into a washout, 1998 and 2007 are good examples of this.

Thanks for that.

But La Niña doesn’t always lead to a poor summer does it?

Back to current models - GFS 6z seems to have ditched the breakdown next weekend.

[LRD]

2 hours ago, Man With Beard said:

They're the latest set of clusters we can see from the ECM, and as I'm sure you'd agree, just looking at one set of ensembles is not as good as looking as looking at two, so I'm interested to see how they will change / not change when the new set were released later. Also, I had been sleeping between 11.30 and 7.30,so it really was the first chance for me, and I guess others, to see them

Thanks MWB. I hadn't seen the clusters from last night so I found it helpful that you posted them. Interesting to see how they compare with this mornings clusters. Will provide a big clue to where we're headed. I suspect it's heading for more and more high pressure domination and dry weather when we now need some rain. 

Edited May 24, 2020 by Blessed Weather
Comment removed.

[Man With Beard]

By popular demand, here are the ECM 00Z clusters, D8 looks like a 50/50 split between something like yesterday's ECM op run (trough over UK) and high pressure building back into the UK instead. 

By D13, anything possible really, but troughs to our south at this time of year often mean the chance of warm or thundery spells, or cluster 4 could be very wet. 

[LRD]

34 minutes ago, Man With Beard said:

By popular demand, here are the ECM 00Z clusters, D8 looks like a 50/50 split between something like yesterday's ECM op run (trough over UK) and high pressure building back into the UK instead. 

By D13, anything possible really, but troughs to our south at this time of year often mean the chance of warm or thundery spells, or cluster 4 could be very wet. 

Thanks again. Day 13, cluster 3 would be nice (might be thundery and probably warm). But it looks like high pressure continues to be the form horse

Edited May 24, 2020 by LRD

[Frosty.]

Looking at the Gfs 6z operational, the week ahead looks VERY GOOD...as in settled for the majority of the u k  and warm / very warm too before it probably loses the plot in low res, looking at the GEFS 6z, for sure there is some absolute crud beyond the week ahead but also some more pleasant outcomes ...so, perhaps early  June could still be decent or better..fingers crossed etc!...let’s remember, it’s not all about what the Gfs / Gefs shows!!!.

Edited May 24, 2020 by JON SNOW

[MATTWOLVES 3]

1 hour ago, Djdazzle said:

Thanks for that.

But La Niña doesn’t always lead to a poor summer does it?

Back to current models - GFS 6z seems to have ditched the breakdown next weekend.

Yes.. Its a good post, and he certainly knows his stuff. But as we are aware there are so many other over riding circumstances that can squander a certain outcome. I've heard it touted many times before in the past that la nina type outcomes would lead to a cold start to winter, or a cold end to winter with neither coming off. Remember those gr8 background signals for Winter in 2018/2019? Well we all know the outcome there... Probably because all those signals got overridden by 1 or 2 other signals.. Like perhaps an IOD.. I wouldn't even like to hazard a guess at the middle part of this summer, let alone this coming winter! Far to many things can crop up at short notice to massively change the outcome at short notice. We'll at least we have some good output this morning... Looking good next week folks... Enjoy..

Edited May 24, 2020 by MATT☀️

[Zak M]

06z GFS is very good today.

It's showing very little signs of a breakdown, especially near the end of the month - where the previous GFS run was showing a breakdown on the 31st

From now up to the end of the month > expect temperatures to soar above 20c. The high twenties are easily possible in the south and perhaps other areas nearby on days 6, 7 and 8

This is when it gets a bit tricky. The GFS has delayed the breakdown up until June 4th - so by then, expect some heavy rain

Edited May 24, 2020 by Zak M

[MATTWOLVES 3]

4 minutes ago, Zak M said:

06z GFS is very good today.

It's showing very little signs of a breakdown, especially near the end of the month - where the previous GFS run was showing a breakdown on the 31st

From now up to the end of the month > expect temperatures to soar above 20c. The high twenties are easily possible in the south and perhaps other areas nearby on days 6, 7 and 8

This is when it gets a bit tricky. The GFS has delayed the breakdown up until June 4th - so by then, expect some heavy rain

Its gonna keep pushing it back Zak... All the way til September 4th..

[matt111]

16 minutes ago, Zak M said:

This is when it gets a bit tricky. The GFS has delayed the breakdown up until June 4th - so by then, expect some heavy rain

By then it’ll probably just be a continuation of the current weather with the way it’s being pushed back. 

[Methuselah]

Et pour les ensembles:

As can be seen, our old friend, the 06Z op is off bungee-jumping from June 3rd!

    

And pressure looks set to fall, but we can all hope it's to our south and not east!

    

That's because I like my rain (if we even get any!) to be warm rain...

[Frosty.]

Gotta say I’m really liking the ECM 0z ensemble mean through most of high res, the week ahead looks really nice for the majority (summer-like)...ok pressure dips towards the end but the Azores high is lurking with intent and who is to say beyond the week ahead won’t turn out better than currently hinted at?..in the mean time, enjoy another cracking bank holiday and week ahead..catch ya later, or more likely tomoz!

 

Edited May 24, 2020 by JON SNOW

[stodge]

Afternoon all

The journey from the end of next week onward remains, as it often is, replete with many paths.

GEM this morning showed what can happen if the second HP from the Azores doesn't get over the British Isles quickly enough or ridges too far north. The European trough moves up from the south and threatens showery if not stormy conditions for southern Britain while further north the fine weather is maintained.

ECM this morning looked quite similar here - the question then becomes as to whether the core of the Azores HP will shift north rather then NE (this was the outcome on the much-derided GFS 12Z yesterday afternoon).

The 06Z GFS OP is actually very good

Further into FI, however, it doesn't really build the ridge east but shifts it north and that alloes the more active trough to the north to come down over Scandinavia and introduce a much cooler airflow.

Control shows the growing influence of the European trough:

Indeed the rest of FI in Control isn't that inspiring as the scenario ends up not far removed from Control. The Mean at T+198 also suggests the influence of lower heights to the south and an E'ly picking up for southern areas.

[Mike Poole]

ICON 12z

Some nice settled weather here, and then the scenario becomes interesting, towards T180 when the ridge from the Azores to Scandi is on, but that cut off low, which we first saw hinted at by yesterday's 12s becomes established, position of that will be crucial in determining the path beyond next weekend.  On this run, potential for thunderstorms for some as the heat is there, T180:

Edited May 24, 2020 by Mike Poole

[Mike Poole]

UKMO T144 looks like it is going the same way.  What is pushing the high over the top?  The low at the far bottom left of the chart is a factor, I think.

[Zak M]

12z UKMO - 96 and 120

30c being reached somewhere next week is certainly possible

   

Edited May 24, 2020 by Zak M

[Methuselah]

GFS at T+96: fine and sunny, but not too hot!

    

It's a stonker!

[Leo97t]

4 minutes ago, Zak M said:

12z UKMO - 96 and 120

30c being reached somewhere next week is certainly possible

   

I don't agree - uppers are just about high enough but feed is too easterly 

Probably just about possible in July but too early off this set up

Possible this might correct to a more southerly flow however 

[mb018538]

3 minutes ago, Leo97t said:

I don't agree - uppers are just about high enough but feed is too easterly 

Probably just about possible in July but too early off this set up

Possible this might correct to a more southerly flow however 

I agree - especially the UKMO tonight, which goes very easterly by 144 and cuts off the very warm air that was starting to build. At the moment I’d say 25-27c looks fair, which is still very good.

[mb018538]

For once - I prefer the GFS! Warmer air source, no wind. 

[Zak M]

6 minutes ago, Leo97t said:

I don't agree - uppers are just about high enough but feed is too easterly 

Probably just about possible in July but too early off this set up

Possible this might correct to a more southerly flow however 

Sorry, you are probably correct - completely forgot to look at the 850hpa temps!

[shaky]

Fantastic 12z ukmo and gfs so far!!!!?

[Allseasons-Si]

It's still looking good Jeff...

UKMO and GFS at 144

there is still some differences at that time but just a variation of the theme which is still pleasantly warm weather,now whether it breaks down to some unsettled weather or thunderstorms is anyone's guess and i like the latest METO forecast too with above average temps,sunny spells and warm,the caveats aply to the NW of the UK but i am sure they will join in on the fine and settled weather. 

Edited May 24, 2020 by Allseasons-si

[Guest]

6 minutes ago, mb018538 said:

I agree - especially the UKMO tonight, which goes very easterly by 144 and cuts off the very warm air that was starting to build. At the moment I’d say 25-27c looks fair, which is still very good.

Also agree, the highest temps look like transferring to the west, Bournemouth, Chivenor and the dodgy sited place in Wales will all do well. For 30C in May (which is as rare as 35C in July/August) you really some decent warm advection from the south, max temps look 26-28C and that's squeezing nearly 20C out of the uppers which is exceptional in its self. ICON so far would probably get you the closest to 30C.

 

Edited May 24, 2020 by Guest

[Mike Poole]

1 minute ago, Zak M said:

Sorry, you are probably correct - completely forgot to look at the 850hpa temps!

I made that mistake yesterday, Zak!  Easily done when the runs are coming out fast.  GFS quite different to UKMO and ICON, looks like continuation of the settled weather with very little impact of the trough feature, T162:

[Leo97t]

Yes worth remembering how dry soil means lapse rates are way way higher at the moment than normal although I'm quite perplexed at the temperatures the GFS is predicting (21-23C) - should be higher than that.

Very different to the BBC with 25-27 for all this week in London