Model Output Discussion - May and Early Summer!

[knocker]

Outlook - the good news is that northern regions will shortly lose the presence of the persistent fronts and enjoy their day in the sun. Albeit they will not enjoy the full benefit from the WAA ingressing the south as the first cold front slips south east quite quickly . But much of England and Wales does and it will be hot in places before the next cold front arrives heralding the arrival the upper trough next week and cooler and more unsettled weather

Meanwhile the NH 500mb profile and the the North Atlantic surface analysis for midnight and the 0300 UTC WV image

But for the moment the the frontal systems are still producing persistent rain in the north and this will continue through the day in N. Ireland, Scotland and the far north of England until the aforementioned cold front clears N. Ireland by 1800. England and Wales are in the broad warm sector so the day dawns cloudy here, particularly in western regions with Stratus and mist but where the cloud breaks it will become quite warm, especially in the east.

The rain will continue for a while this evening as the front tracks south east but fizzles out by midnight as the front weakens leaving a few showers in it's wake over northern Scotland. Elsewhere broken cloud and quite mild.

The cold front gets stuck across the country on Saturday and starts edging north again as a warm front and south of this it becomes sunny and hot and consequently, whilst also sunny in the north, the temps will be much lower.

But over Saturday night another low has developed at the base of the upper trough that is edging closer and this tracks north east to be 993mb west of N. Ireland by midday Sunday with the associated cold front lying down western Scotland, Wales and the south west of England. The patchy rain from the associated warm front will quickly clear the north but the belt of rain from the cold front will move slowly east through Sunday and as it has become quite hot preceding this, thundery outbreaks are a distinct possibility.

By Monday the upper trough dominates the eastern Atlantic but the subtropical high is again amplifying in mid Atlantic. On the surface the cold front has cleared to the east as the low tracks north of Scotland leaving the country in a much cooler showery day which may be quite frequent over Scotland courtesy of the occlusion wrapped around the low.

By Tuesday the trough has become quite elongated courtesy of the continuing amplification, with two surface centres, one of which is over the UK. With a myriad of troughs around in this unstable environment another day of sunshine and showers with perhaps longer periods of rain as they coalesce.

[Guest]

6 minutes ago, CreweCold said:

Depends what you like. Some tasty diurnally driven convection showing on GFS, which produces some potent thunderstorms. Lovely jubbly IMO. 

Agreed but they are generally low topped,  not overly prolific lightning produced, drop out in the evening leaving cool to cold....

just aside from the longer range forecast and as usual in these situations the models struggling with the depth of the cloud across the south this morning, very heavy drizzle (it’s rain) been going for a couple of hours, cloud could be a real pain along the south coast today....

[knocker]

To continue briefly with the gfs.

The NH 500mb profile by midday Wednesday and expected surface analysis

And through the rest of the week the 'feed' to the trough continues between the intensifying east European high and the mid Atlantic ridge and thus continuing unsettled

 

[Guest]

Not sure what is more disappointing this more the view out my window under overcast skies and heavy drizzle or the GFS ensembles, only a few big outlier members drag the mean towards average beyond next weekend the majority follow the ops run keeping things highly unsettled and wet for the first half of June. Not a happy Friday  

Edited May 31, 2019 by Alderc

[Frosty.]

The GEFS 00z mean looks better and better between approx 10th to 16th June, there is plenty of scope for strong ridging / high pressure, continental heat and thunderstorms. As for next week it's going to turn cooler and fresher with sunshine and scattered showers, coolest and most unsettled further NW but it could become much warmer and more humid again, at least further s / e towards or by the very end of next week.

Edited May 31, 2019 by Frosty.

[tinybill]

1 hour ago, Penrith Snow said:

My God, if you don't like wet weather then don't look at the overnight GFS  run!

Its basically very unsettled throughout with the UK under a upper though right out to Day 10.

Upper temperatures improve next weekend but as one low fills another moves up from the south  which would bring heavy rain and thunderstorms although a suspect temperatures would be back to normal in the north May be a tad above in the south.

All the heat is over eastern Europe and Russia under a pronounced upper ridge.

Not good, not good at all.

Andy

http://www.meteociel.fr/modeles/gfse_cartes.php?mode=2&ech=204

just looked deep into fantasy  world no sign  of summer there  yet!!

[Guest]

ECM also looking increasingly disturbed, any talk of it becoming warmer beyond next weekend is pure speculation. All models whether we like it or not are pointing heavily towards a slightly more lengthy unsettled spell. 

Re the GFS mean, I think the blended solution is poor guidance currently, a few significant outliers in the ensemble pack are dragging it to more favourable viewing, while those outliers can’t be completely discounted they currently appear most unlikely. 

Edited May 31, 2019 by Alderc

[knocker]

Little to add vis the ecm initially but towards the end of the run it does shift the original trough east as another one drops into the Atlantic and tracks east.

[mb018538]

10 minutes ago, Alderc said:

ECM also looking increasingly disturbed, any talk of it becoming warmer beyond next weekend is pure speculation. All models whether we like it or not are pointing heavily towards a slightly more lengthy unsettled spell. 

Re the GFS mean, I think the blended solution is poor guidance currently, a few significant outliers in the ensemble pack are dragging it to more favourable viewing, while those outliers can’t be completely discounted they currently appear most unlikely. 

I would tend to agree - the met office extended forecast keeps stating that drier and more settled weather should become established towards mid month....looks fanciful to me, nothing really showing a break from the unsettled weather around that point at the moment. We will see.

[knocker]

The 0600 sat image sums up the current analysis

[Guest]

1 minute ago, knocker said:

The 0600 sat image sums up the current analysis

#clagfest 

To be fair, although it’s still drizzling the sun has broken through so promising further inland. By 10/11am most of the cloud should have melted back to within a few miles of the coast, moist airmasses like this in late spring are a pain in general. 

[knocker]

8 minutes ago, mb018538 said:

I would tend to agree - the met office extended forecast keeps stating that drier and more settled weather should become established towards mid month....looks fanciful to me, nothing really showing a break from the unsettled weather around that point at the moment. We will see.

The update that I can see says "Towards the middle of the month some drier and more settled conditions may begin to become established across the UK"

[Methuselah]

After yesterday's runs, this morning's 00Z is a bit of a return to Earth. Though the gradual over all warming trend continues:

And the trusty FV3 once again ends on a high, and both models have ditched next weekends fun-and-games -- no surprise there:

00Z GEFS ensembles are nowt to write home about: 

But the rain's still there! 

Edited May 31, 2019 by Ed Stone

[Sky Full]

The following charts from the ops this morning do not bode well for next weekend - or indeed for the start of summer.....

ECM.                                                           GFS

   

GFS(P)                                                       GEM

   

Cyclonic, windy and cloudy with cool air above us - could be looking at March rather than June.  Not saying that Summer is over, just that it is having a very hesitant start.....   This could all change at the drop of a hat and some of us might be complaining about temperatures being too high and rainfall non-existent by the end of the month.  But then I also believe that Spurs will win the CL tomorrow....

 

 

 

[StormChaseUK]

Looks like a cool cloudy dry summer ahead. 

Lack of rain is concerning  

[Guest]

2 minutes ago, StormChaseUK said:

Looks like a cool cloudy dry summer ahead. 

Lack of rain is concerning  

Not sure how you can say dry, GFS has 40-70mm across most of E+W through its run and is not an outlier, this week theme is continued in other models. That alone is enough to get us though the remainder of summer given there will undoubtedly be other wetter interludes unless the weather goes all 1995 on us! 

[East_England_Stormchaser91]

2 hours ago, CreweCold said:

Depends what you like. Some tasty diurnally driven convection showing on GFS, which produces some potent thunderstorms. Lovely jubbly IMO. 

Aye, some decent homegrown convection. But imports seem to be doing their usual thing and shifting off to the east . 

Looks like for now, we’ve had our turn last year for the sun, now Eastern Europe and Russia seem to be bathing in it. Can’t have it all. Then again, Britain wouldn’t be Britain without the rain! Welcoming for our farmers at least. 

Edited May 31, 2019 by East_England_Stormchaser91

[mb018538]

7 minutes ago, StormChaseUK said:

Looks like a cool cloudy dry summer ahead. 

Lack of rain is concerning  

Doesn’t look dry to me! Plenty of rain, especially in the NW. 100mm In 10 days is flood risk territory.

[northwestsnow]

33 minutes ago, mb018538 said:

Doesn’t look dry to me! Plenty of rain, especially in the NW. 100mm In 10 days is flood risk territory.

Yes , looks really very wet in the North west.

Watching brief for me, of course the first 10 days or so (not inc today/tomorrow) is pretty certain to be crud of you want summer, but lets hope thereafter things begin to settle down.

 

[Guest]

48 minutes ago, StormChaseUK said:

Looks like a cool cloudy dry summer ahead. 

Lack of rain is concerning  

Where's your evidence for this? So you're forecasting below-average temperatures and precipitation for the summer months?

I do find these one-liner summer forecasts amusing and confusing in equal measure  As others have stated above we're actually in line for a fairly wet start to summer, though I think those precip charts do exaggerate totals somewhat

[Frosty.]

The day 10 Ecm 00z ensemble mean doesni look bad further south with ridging, and the operational also ends with a traditional north / south split, nae bad for the south, crap for the north.

Edited May 31, 2019 by Frosty.

[Methuselah]

24 minutes ago, Why said:

Where's your evidence for this? So you're forecasting below-average temperatures and precipitation for the summer months?

I do find these one-liner summer forecasts amusing and confusing in equal measure  As others have stated above we're actually in line for a fairly wet start to summer, though I think those precip charts do exaggerate totals somewhat

Well, Spring has been so 'dire', I think I'm in danger of overdosing on Vitamin D. The doomsday predictions have been far off-the-mark, and I don't see them coming true now...Famous last words?

Edited May 31, 2019 by Ed Stone

[danm]

1 hour ago, StormChaseUK said:

Looks like a cool cloudy dry summer ahead. 

Lack of rain is concerning  

This isn’t a prediction for the entire summer I hope? That would be futile. Meteorological summer doesn’t even start until tomorrow. 

[Frosty.]

Just looking at the Gfs 00z operational for next week, it doesni look too bad, in a nutshell it's sunshine and showers, some heavy with thunder and temps into the high teens celsius, maybe close to 21c at times further southeast but cooler across northern uk. Beyond next week there's more ridging / high pressure than low pressure through low res.

Edited May 31, 2019 by Frosty.

[knocker]

The four day trend of the ext mean EPS anomalies shows a reasonable consistency and if it's on the money today the evolution will have the trough weakening and retrogressing west as the European ridge does the same.This would portend more settled weather with temps creeping above average

Last night's NOAA is not quite in the same ball park, but pretty close. but as it's a reasonable quick development tonight's may well be more relevant

Edited May 31, 2019 by knocker