Storm & Convective Discussion - 12th June 2015 onwards

[Chris K]

I have to be honest, I don't see much potential from Tuesday Night/Wednesday for anyone other than those straddling the weak cold front moving in from the west and even then, I'm not so sure it's likely to be anything of note - certainly in terms of coverage. It could be one of those events where an isolated storm smashes into the town down the round and you can barely see a cloud in the sky from your window at home. I wouldn't be considering a chase day as such, that's for certain.

 

 

Not sure - I have not seen the latest model guidance for storm inhibitor indications such as CIN, soaring index and how much energy will be required to break the cap, but the surface trough feature indicated by the attached fax charts may also add storms to the mix. Western areas Tues night/Weds. Some good potential for more NE areas Weds afternoon due to the good timing with peak heating and then coastal areas in the NE Weds evening/night.

 

I am following the fax charts mostly now alongside local forecasts. After the last debacle, some of the high resolution models showed storms right up until the morning in my area, whereas the Met Office weren't going for it.

 

Let's just hope the cap can be broken this time. We have a good setup here and it really would be surprising to end up with mass disappointment again. Although let's face it - it can happen...

 

Edited June 29, 2015 by Chris K

[sn0wman]

I so hope you are right Sn0wman. I'm gleeful one minute, and in despair the next. Will just have to wait patiently and see if any storms erupt over my area. Could do with a right cracker or two...or three...

So do I Been waiting for ageees for a good thunderstorm - they're as rare as hen's teeth around here. Not going to get too excited for Wednesday, as storms are so hit and miss really.

[Guest]

From my back yard perspective, it hasn't looked like being an interesting week at all.

Temperatures haven't been progged to to be anything special (remains to be seen) and i haven't seen enough to make me think "yippee" on the storm front, either.

 

However, looking at the FAX chart (as weather history pointed out yesterday) a trough is still showing from Northern Ireland, down through Wales and in to the South West.

 

brack1a.gif

 

While there's no yippee's, yet, there's still a lot to play for.

 

Couldn't agree more, temps are going to be nice but pretty average given proximity to sea, today being a perfect example. Was 19C at 9am fives hours later under rising uppers and continuous sunshine its 20C.

 

Storm wise I think it'lll be a complete no go and trailing/decaying fronts will just inhibit temp rises opposed to firing off storms.

[cheese]

I have to be honest, I don't see much potential from Tuesday Night/Wednesday for anyone other than those straddling the weak cold front moving in from the west and even then, I'm not so sure it's likely to be anything of note - certainly in terms of coverage. It could be one of those events where an isolated storm smashes into the town down the round and you can barely see a cloud in the sky from your window at home. I wouldn't be considering a chase day as such, that's for certain.

WRF-NMM disagrees with you as it shows storms breaking out in NW England before transferring over the Pennines into Yorkshire - but we'll see. Personally I'm feeling confident for the first time in ages.

[sn0wman]

Neither of you have said where you are getting "that" from. I take yours is just a "guess" too??

I don't have enough time to post the relevant charts atm - will do when I get back home. No, it wasn't a guess at all (bit rude to say that?). I've been following the situation closely, researching past events and using various models, especially the WRF-NMM, which is pretty accurate in this timeframe, so I have a good (by no means the best) understanding of the set-up this week.

[Chris K]

Couldn't agree more, temps are going to be nice but pretty average given proximity to sea, today being a perfect example. Was 19C at 9am fives hours later under rising uppers and continuous sunshine its 20C.

 

Storm wise I think it'lll be a complete no go and trailing/decaying fronts will just inhibit temp rises opposed to firing off storms.

 

I am a little confused where people are getting the idea of decaying fronts from? Yes they will weaken if moving into higher pressure (decreased instability). And trailing, yes, but the fax charts do not currently show the cold front as weakening. A decaying front is indicated by line markers along the front (almost like little crosses)

Edited June 29, 2015 by Chris K

[Azazel]

praying for Friday night to deliver here. Imports from France pretty please. Don't think we've got much chance otherwise:(

[Harry]

WRF-NMM indeed going for very little away from more N and W areas. GFS by contrast breaking out widespread thundery activity. 

 

WRF-NMM interestingly also not wanting to deliver much across France which I find hard to accept. 

 

So, huge divergence between WRF-NMM and GFS...at the current time I'm more inclined to favour GFS.

[Nick L]

WRF-NMM indeed going for very little away from more N and W areas. GFS by contrast breaking out widespread thundery activity. 

 

WRF-NMM interestingly also not wanting to deliver much across France which I find hard to accept. 

 

So, huge divergence between WRF-NMM and GFS...at the current time I'm more inclined to favour GFS.

 

Goes against the ECM too, which shows plenty of thunderstorm potential over much of the country at some point in the coming days.

[stevofunnelcl]

Not feeling confident on storms now, got carried away with all the hype over the weekend

Some warm pleasant weather on either side, but in terms of the west, it seems the heat will be a short-lived affair

 

I think it'll be the usual story by the end of the week, people watching massive storms (possible MCS) over France, and hoping it travels over the Channel, and into the south-east

[Wilxy]

Just out of interest when storms develop which level of winds do they usually travel, 850hpa, 700 or 500hpa its been bugging me because sometimes they don't always follow 850hpa?  

[Biggin]

Goes against the ECM too, which shows plenty of thunderstorm potential over much of the country at some point in the coming days.

Thanks Nick.

[A.J]

Couldn't agree more, temps are going to be nice but pretty average given proximity to sea, today being a perfect example. Was 19C at 9am fives hours later under rising uppers and continuous sunshine its 20C.

 

Storm wise I think it'lll be a complete no go and trailing/decaying fronts will just inhibit temp rises opposed to firing off storms.

I disagree, not a little, but a lot....I expect plenty of elevated convection during the latter half of the week as WAA is destabilized as shortwave troughs moving in from the south west generating plenty of forced ascent......for southern counties, mid-level instability is more of a player than surface based convection....so best advice is to look at the upper parameters, T500, theta-e, PWAT, DLS, MLCAPE etc......There is a much used fallacy that the English Channel kills imports.....It only hampers surface based thunderstorms that drift northwards from the French Coast, the Channel per se, does not affect elevated thunderstorms...Elevated thunderstorms pushing into Britain from the continent that do weaken, because generally speaking Britain lies on the NW flank of Spanish Plumes and as such, there's less latent instability 

 

 

hopefully NF, Brick & W09 will post their thoughts as we get closer

Just out of interest when storms develop which level of winds do they usually travel, 850hpa, 700 or 500hpa its been bugging me because sometimes they don't always follow 850hpa?  

they don't Tom...as a rule of thumb, I use the 500 & 300hpa vectors (especially for elevated storms)

Edited June 29, 2015 by ajpoolshark

[Harry]

hopefully NF, Brick & W09 will post their thoughts as we get closer

they don't Tom...as a rule of thumb, I use the 500 & 300hpa vectors (especially for elevated storms)

 

Indeed, but not an exclusive rule (as we know) particularly if any MCS features develop, which can have a mind of their own and stick two proverbial fingers up at steering winds...."oh NE to Benelux is it, nah mate, I fancy a bit of a change and a northerly trip up the English heartlands thank you very much" 

Edited June 29, 2015 by Harry

[fazer76]

There's very little doubting the ingredients remain ripe for a very good show indeed for some. As per usual other places may well miss out but am presently liking overnight Wednesday into Thursday morning     again Friday into Saturday offers plenty of action for other parts of the UK.  

[A.J]

Indeed, but not an exclusive rule (as we know) particularly if any MCS features develop, which can have a mind of their own and stick two proverbial fingers up at steering winds...."oh NE to Benelux is it, nah mate, I fancy a bit of a change and a northerly trip up the English heartlands thank you very much" 

very true H 

[Darren Bown]

Seem to be placed quite well for Wednesday. Fingers crossed!

[Stuart]

I am in a good risk area on Wednesday

[StormChaseUK]

Good signs already

Temps have already exceeded the GFS max of 24C reaching 26/27C already. 

[Harry]

Hmmm...may be premature but 12z signally a bit of an easterly shunt mid-week...also only keen to break out storms (for the SE corner) in the Thames Estuary 

 

......doubt beginning to creep in for my neck of the woods I have to say!

[Darren Bown]

ESTOFEX have western UK under a chance of thunderstorms tomorrow.

[richep]

Chance for my area tomorrow evening according to netweather storm risk , and again friday afternoon/evening.

[Darren Bown]

Are these ACas clouds?

[Mapantz]

Are these ACas clouds?

 

Just Altocumulus, i would say.

[Darren Bown]

Just Altocumulus, i would say.

Yes you're right, they've not much height to them. Just rolled in now after a very warm afternoon.