Convective Storm/Discussion thread - 11/06/16 onwards

[weather09]

11 minutes ago, Nick F said:

With regards to the next storm potential, both 12z GFS and ECMWF hinting at strengthening WAA ahead of digging trough to west of Iberia and Biscay Weds/Thurs combining with a thundery low moving NE across northern France to bring a threat of convective rainfall to the SE early Thurs. ECMWF CAPE charts on wxbell show several  100 j/kg Thursday morning too. Long way off though, with the usual shift of the risk away on to the near continent possible! Here's precip from ECMWF for 06z Thursday ...

Hi Nick. Presume the ECMWF CAPE outputs are available at a premium?  Always wanted to view these ahead of storm risk days. Do you find that the ECM is more conservative with CAPE values compared with the GFS and more closer to reality? 

I think I tried a limited trial version out a while back, not sure which site, but vaguely remember it not being in spring or summer, so didn't really get to see any noteworthy CAPE outputs. 

[Nick F]

18 minutes ago, weather09 said:

Hi Nick. Presume the ECMWF CAPE outputs are available at a premium?  Always wanted to view these ahead of storm risk days. Do you find that the ECM is more conservative with CAPE values compared with the GFS and more closer to reality? 

I think I tried a limited trial version out a while back, not sure which site, but vaguely remember it not being in spring or summer, so didn't really get to see any noteworthy CAPE outputs. 

Hi, yes unfortunately they are premium, so can't post them on here. They are increasing their subscription rates soon too, so I don't think it's worth justifying to continue with their sub, just for the benefit of seeing their CAPE, snow, 32 days ahead charts, etc. Precip charts out 240hrs are freely available and generally the GFS CAPE charts are a reasonable guide, albeit you need to tone down their projections by a few 100 j/kg ... more in line with EC.

Don't think EC are always closer to reality to where instability develops as it projects, but I suppose this is because the higher resolution of the modelled CAPE projections is never going to match the reality of actual local conditions (which can be affected by changes in cloud cover, topography, temperature and moisture changes, wind shifts) which can affect storm development on a local scale to make it inherently difficult for models to reslove accurately.

Edited June 17, 2016 by Nick F

[Nick F]

Looks like that band of heavy convective rain moving SE over N and W London currently may still squeeze out the odd flash and rumble as per recent strike activity to the W and NW of London ... but not expecting anything more than heavy when it reaches here on the south side of the big smoke.

Edited June 17, 2016 by Nick F

[Hodgheg]

No lightning in this interesting feature coming across south London. Had a shot of heavy rain. Maybe we could call this a mini bow echo! 

[Harry]

56 minutes ago, chapmanslade said:

CAPE isn't the be all and end all mind

 

It is only 'potential' without a trigger

Indeed, but I'd take a heatwave any day, especially after the slow start to summer it has been so far! 

[SenlacJack]

1 hour ago, Nick F said:

Looks like that band of heavy convective rain moving SE over N and W London currently may still squeeze out the odd flash and rumble as per recent strike activity to the W and NW of London ... but not expecting anything more than heavy when it reaches here on the south side of the big smoke.

Keeping an eye on that as it appears to be heading my way.

[William Grimsley]

Well, that's that amazing convective period over (especially for this area), this coming week looks rather bland until next week when we see another area of very warm and humid air move up from the continent bringing thunderstorms. 

[Supacell]

1 minute ago, William Grimsley said:

Well, that's that amazing convective period over (especially for this area), this coming week looks rather bland until next week when we see another area of very warm and humid air move up from the continent bringing thunderstorms. 

It has been a very good start to the storm season. As a storm chaser I have had my most active start to a season ever, although this could also be down to my having better equipment now for finding a storm than I did say 5 or more years ago. Let's hope for some more good convective periods between now and October

This coming week is not bland for areas in the southeast. Around midweek there looks like a chance of some continental imports, although it is obviously subject to the usual eastward shift into Holland and Belgium. It is something for people in that corner of the country to watch though before, as you say, more continental goodness being hinted at in FI

[Supacell]

Just a couple of pictures from last weeks storm chases

 

[East_England_Stormchaser91]

6 hours ago, Supacell said:

Just a couple of pictures from last weeks storm chases

 

Where was the 2nd one taken? Looks like one that I observed from Royston looking towards MK and Luton, which I'm sure was a +CG! 

[Supacell]

15 minutes ago, East_England_Stormchaser91 said:

Where was the 2nd one taken? Looks like one that I observed from Royston looking towards MK and Luton, which I'm sure was a +CG! 

It was further east than that, somewhere to the east of Cranfield and looking south. 

[Mapantz]

I'm just awaiting to see what the 18Z shows, but the 12Z shows a little bit of interest for a few areas on Wednesday as a tongue of warm, moist air creeps up and cuts across parts of Southern and Eastern England. It's four days away, and will probably get shunted to the near continent, but you never know!

  

 

[William Grimsley]

Don't want anything convective this week as I'm in St Ives till Saturday!

[East_England_Stormchaser91]

37 minutes ago, William Grimsley said:

Don't want anything convective this week as I'm in St Ives till Saturday!

St Ives Cambridgeshire (more convective one!) or st Ives Cornwall? 

 

Also, OMG  where has this came from!!! Only 4 days away!!! 

Edited June 18, 2016 by East_England_Stormchaser91

[shaky]

18z brings monster amount of cape levels across england wednesday thursday across england!!the plume seems to be pushing further and further west for midweek!!dont see that very often!!

[Costa Del Fal]

Found a great twitter feed of an Environment Agency flood cam at Mushroom Green in the area where the Mousesweet Brook and Black Brook meet near me. Images are posted every few hours (daylight only in general). Here it is: https://twitter.com/B645BX?ref_src=twsrc^tfw

Go to the 16th/17th June. It gives a great overview of how clear the trash screen and surrounding area was all clear and in good condition until late afternoon on Thursday. Then the water rises very high coming some way up the camera pole with water covering almost the whole image. And now what is left is so much debris washed down in the powerful flood. Incredible. 

[alexisj9]

8 hours ago, Supacell said:

Just a couple of pictures from last weeks storm chases

 

wow that second lightning looks loud.

[alexisj9]

20 minutes ago, East_England_Stormchaser91 said:

St Ives Cambridgeshire (more convective one!) or st Ives Cornwall? 

 

Also, OMG  where has this came from!!! Only 4 days away!!! 

erm not sure I want that, looks positively scarey. Considering we've had a couple of storms with this set up, but much less Cape this year, that really took off big time here. 

[East_England_Stormchaser91]

9 minutes ago, alexisj9 said:

erm not sure I want that, looks positively scarey. Considering we've had a couple of storms with this set up, but much less Cape this year, that really took off big time here. 

It does. I know it's a long way off and not quite in hi resolution territory yet, but with the added wind shear overlapping this incredible potential energy, and with the heat low modelled to be the ingredient that would erode the capping, I wouldn't rule out some potential rivalry for storm of the decade under that setup shown. Supercells on a true scale like 28/06/2012 would be a high possibility. 

I wont get carried away too soon yet however. 

Edited June 18, 2016 by East_England_Stormchaser91

[William Grimsley]

9 hours ago, East_England_Stormchaser91 said:

St Ives Cambridgeshire (more convective one!) or st Ives Cornwall? 

 

Also, OMG  where has this came from!!! Only 4 days away!!! 

Definitely Cornwall, ah well we should get some thunderstorms this week if it's going further west.

[A.J]

one run on the GFS has WAA from Iberia with an increased western extent.....the more trusted ECM (IMO) has same plume of warm air clipping the SE and quickly pushed into the near continent which has been modelled for the past few runs....If I was a betting man, I know which solution I'd have my money on

Edited June 19, 2016 by ajpoolshark
grammar

[William Grimsley]

11 hours ago, William Grimsley said:

Don't want anything convective this week as I'm in St Ives till Saturday!

* Carbis Bay

[weather09]

5 minutes ago, ajpoolshark said:

one run on the GFS has WAA from Iberia with an increased western extent.....the more trusted ECM (IMO) has same plume of warm air clipping the SE and quickly pushed into the near continent which has been modelled for the past few runs....If I was a betting man, I know which solution I'd have my money on

Yes, and UKMO-GM as well has a more easterly solution to the 500mb pattern and therefore surface low pressure, keeping main region of instability over mainland, so hard to get too interested in recent GFS modeling.  More often than not a game of 'catch up'  with GFS in relation to euros.

Though, for fun, if something like the last couple of GFS runs were to verify, would see risk of severe thunderstorms, possibly supercells, given overlap of strong shear and moderate/large CAPE. So a Jun 28 '12.  

[A.J]

7 minutes ago, weather09 said:

Yes, and UKMO-GM as well has a more easterly solution to the 500mb pattern and therefore surface low pressure, keeping main region of instability over mainland, so hard to get too interested in recent GFS modeling.  More often than not a game of 'catch up'  with GFS in relation to euros.

Though, for fun, if something like the last couple of GFS runs were to verify, would see risk of severe thunderstorms, possibly supercells, given overlap of strong shear and moderate/large CAPE. So a Jun 28 '12.  

I have taken the preliminary precaution of changing my customer schedule this week and decided to see my East Midlands and Lincolnshire customers on thursday...A lot of driving for sure and of course it has absolutely nothing to do with the overnight GFS 

[East_England_Stormchaser91]

As expected, a big shift east on the 06z run. SE and East Anglia would be the best spots now for anything interesting. Most of the real fun and games would remain the other side of the water