Model output discussion - 20th Feb onwards

[Singularity]

  

That low north of the Azores in 6 days time truly is our saviour if you're seeking the warm but somewhat unstable outlook with rounds of afternoon thunderstorms; it interacts with the Iberian trough in a way that draws the focus for lower heights west, with a ridge developing to the E/NE and a decent feed of air from the south to the UK. 

GFS has added this feature in on the 12z, hence the much improved incursion of warmth from Sunday onward. It's still a bit fiddly on Saturday though, whereas ECM shows a quicker advance of the warm air with rain quickly becoming confined to the NW, this exiting into the N. Atlantic by Sunday.

ECM has been upping the magnitude of the warm air advection toward the UK over the past few runs, and now looks nothing short of remarkable in the 9-10 day period in terms of the weather pattern:

 

The uppers are far from noteworthy, which is due largely to the focus of the ridge being more to the NE than SE, but maximums at 2m in the south would still be in the mid-20's in between the showers. Sultry, mid-late July like weather - in early May! Not bad going if it does happen. Good to see GFS moving in the right direction and with generally decent consistency in terms of having that LP a fair way off (but not too far, if you get what I mean) to the SW of the UK out to at least day 11 or 12.

[Frosty.]

Bring on the warmth! The Ecm 12z shows a big warm up with temps climbing into the low to mid 20's celsius as we draw a plume of continental air northwards into the UK. There is now plenty of support across the models for a marked pattern change and I for one am very happy about it!

[DTHFCJ]

Agree Frosty up up go the temps bout time!

 

[Frosty.]

6 minutes ago, DTHFCJ said:

Agree Frosty up up go the temps bout time!

 

Yes it's about flippin time we had a change we had a winter with no winter and a spring with no spring so far but a marked pattern change to much warmer weather is taking shape for late spring, the transition is already underway with temps recovering to seasonal levels, into the 13-16c range but then it looks like it will become much warmer according to the latest models and importantly, the met office too!

[Man With Beard]

This is a serious tease...

http://www.cpc.ncep.noaa.gov/products/predictions/814day/500mb.php

Looking slightly above 50% chance now of a ridge setting up to favour warm (hot?) southerlies in the middle third of the month. But that trough to the SW will surely interfere at some point. Might be some big winners and big losers out of this (heat/sun/thunder wise).

I would suggest a shock 80F is not out of reach as a best case scenario. But some sort of 70F plus looks a good bet in places.

[William Grimsley]

This is starting to look really promising with temperatures well into the 20's°C through the week after next! I'm off to Marlow on the 15th of May, that could be quite a good shot to say I could be staying in a "thunderstorm hotspot"!

[Paul]

Pictures maybe tell a thousand words here - ensembles vs the climate average

1st - 3rd May

4th - 6th May

7th - 9th May

10th - 12th May

13th - 15th May

Lots of good info about the potential warm-up in the blog Nick wrote this evening too:

http://www.netweather.tv/index.cgi?action=news;storyid=7331;sess=

[knocker]

1 hour ago, Man With Beard said:

This is a serious tease...

http://www.cpc.ncep.noaa.gov/products/predictions/814day/500mb.php

Looking slightly above 50% chance now of a ridge setting up to favour warm (hot?) southerlies in the middle third of the month. But that trough to the SW will surely interfere at some point. Might be some big winners and big losers out of this (heat/sun/thunder wise).

I would suggest a shock 80F is not out of reach as a best case scenario. But some sort of 70F plus looks a good bet in places.

I'm not sure I follow serious tease or that the trough will interfere at some point MWB. It's the combination of the orientation of both the trough and the ridge, at the moment, that looks as if it will create this very favourable analysis. Of course if the whole pattern moved a tad east then that would be a different matter but if anything the movement is  west and towards the end of the period the wind has veered WSW with temps moving towards average. But everything is looking hunky dory at the moment.

Both the GEFs and EPS 9-14 are very similar to NOAA, although the latter, which I can't post, perhaps has the trough more negatively tilted. No matter the flow is still around SSW with temps well above average.

Edited April 30, 2016 by knocker

[Frosty.]

Check out the Ecm 12z ensemble mean guys, it's a stonker for warmth as time goes on and a great way to end the day. The models are firming up on a pattern change from the recent unseasonably cold to what looks like becoming unseasonable warmth from the end of next week onwards!

[Man With Beard]

16 minutes ago, knocker said:

I'm not sure I follow serious tease or that the trough will interfere at some point MWB. It's the combination of the orientation of both the trough and the ridge, at the moment, that looks as if it will create this very favourable analysis. Of course if the whole pattern moved a tad east then that would be a different matter but if anything the movement is  west and towards the end of the period the wind has veered WSW with temps moving towards average. But everything is looking hunky dory at the moment.

Both the GEFs and EPS 9-14 are very similar to NOAA, although the latter, which I can't post, perhaps has the trough more negatively tilted. No matter the flow is still around SSW with temps well above average.

But knock, can you ever recall a summer trough to our SW that doesn't eventually find its way to us? It's a 3 hot days and a thunderstorm style set-up for me. The benefit of the orientation I suppose is that more warm weather might follow on behind.

Edited April 30, 2016 by Man With Beard

[knocker]

8 minutes ago, Man With Beard said:

But knock, can you ever recall a summer trough to our SW that doesn't eventually find its way to us? It's a 3 hot days and a thunderstorm style set-up for me.

I don't recall what I had for breakfast these days MWB let alone past summers. You may well be right but as of this moment the EPS has about five days before the trough becomes orientated west/east which could actually produce some fun and games convection wise. If it's of any interest the EC32 had this transition around the 13th

Edited April 30, 2016 by knocker

[knocker]

Still on track this morning for a few days of very warm weather with the upper trough/ridge nicely aligned.

[Frosty.]

The Gfs 00z op shows an early taste of summer from next Friday onwards with temps soaring into the 20's celsius with very warm spells of sunshine and storm enthusiasts get to fill their boots on this run with plenty of T-Storms breaking out in response to the v warm and increasingly humid continental conditions...it's a cracker!

[William Grimsley]

Not really sure why the GFS has most thundery activity more northward when the actual heat is to the south, to be honest, as I mentioned in a previous post, most thundery weather will be more towards the center of the low e.g. South West England!

[knocker]

As a general overview the ecm has low pressure situated in the W > S quadrant in relation to the UK. It makes little of the ridge to the east so a slack southerly/easterly wind pattern with temps above average but not excessively so.

[knocker]

2 minutes ago, William Grimsley said:

Not really sure why the GFS has most thundery activity more northward when the actual heat is to the south, to be honest, as I mentioned in a previous post, most thundery weather will be more towards the center of the low e.g. South West England!

I'd be very wary of trying to pin down thundery activity at this range when the surface analysis isn't even sorted.

[William Grimsley]

3 minutes ago, knocker said:

I'd be very wary of trying to pin down thundery activity at this range when the surface analysis isn't even sorted.

Fair play, but every model seems to want to agree of a warm and thundery spell by the end of next week.

[Singularity]

Interesting to see the potential from ECM for continued upstream amplification to provide further sliding lows into the western periphery of the trough SW of the UK, which would bring about another shift back west min as occurs during the weekend.

Thats the best way to stave off a move of the trough right up across the UK. GFS falls short of that on the 00z but does try to recover things late in the run. Heat builds notably over Europe too - I expect that will reach heatwave levels just as we find ourselves in the boundary with cooler conditions and hence unsettled, but that's a matter for another time. Let's get the warm weather in first!

In that respect the 00z GFS is pleasing in that temps are into the 20's Friday onward across the south as opposed to Sun/Mon onward. The periphery of the warmth is further NW with more of the U.K. benefitting from a marked temperature rise compared to recent times

[Weather Boy]

Looking at Frosty's charts in particular, may I ask whether GFS still undercooks the temperatures or have recent upgrades ironed out that problem. Anyone know?

[Frosty.]

The Ecm 00z turns into a peach of a run with an early taste of summer, temps reaching 20c in the south by next Friday and then going higher and higher, reaching the low to mid 20's celsius with increasing humidity and a growing chance of thunderstorms but with plenty of very warm sunshine too...following all the unseasonably cold weather recently, this will be a welcome change!

[East_England_Stormchaser91]

1 hour ago, William Grimsley said:

Not really sure why the GFS has most thundery activity more northward when the actual heat is to the south, to be honest, as I mentioned in a previous post, most thundery weather will be more towards the center of the low e.g. South West England!

Probably because there is a decent fetch over the heated landmass, destabilising more and more, the further it travels over the land. 

The southwest will only really do well with elevated storms, given the fact that the English Channel is still cool at this time of the year. If anywhere is going to see decent sferic activity, it will be the Southeast into E England + Midlands as this is where the highest temps and highest instability will be. Plus the real heat to tap into off NE France and Benelux. 

[Gordon Webb]

14 minutes ago, East_England_Stormchaser91 said:

Probably because there is a decent fetch over the heated landmass, destabilising more and more, the further it travels over the land. 

The southwest will only really do well with elevated storms, given the fact that the English Channel is still cool at this time of the year. If anywhere is going to see decent sferic activity, it will be the Southeast into E England + Midlands as this is where the highest temps and highest instability will be. Plus the real heat to tap into off NE France and Benelux. 

this is assuming it pans out like it's currently modeled plently of time for subtle or not so subtle changes which may change the setup one way or the other

[knocker]

The ecm ens 850mb temp and anomaly. Moving foward the EPS 8-13 anomaly is very similar to the GEFS posted earlier so at this stage we are looking at a quite a few days with temps above average but of course the detail regarding weather awaits to be resolved.

 

[William Grimsley]

54 minutes ago, East_England_Stormchaser91 said:

Probably because there is a decent fetch over the heated landmass, destabilising more and more, the further it travels over the land. 

The southwest will only really do well with elevated storms, given the fact that the English Channel is still cool at this time of the year. If anywhere is going to see decent sferic activity, it will be the Southeast into E England + Midlands as this is where the highest temps and highest instability will be. Plus the real heat to tap into off NE France and Benelux. 

Maybe, but there's a hell of a lot of mid level instability coming in next week!

[Convective]

7 minutes ago, William Grimsley said:

Maybe, but there's a hell of a lot of mid level instability coming in next week!

I can remember many a time when the most violent storms broke out over the northern half of England before moving into Scotland, due to the humid continental air mixing with the cooler temperatures the further north. Either way, plumes can deliver storms just about anywhere so its safe to say I'm quite looking forward to the progression of this potential set-up, even more so now that the majority of models have come into agreeance