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

[Mapantz]

1 hour ago, William Grimsley said:

Yes, not currently, but there was a result of nearly 70 mph. @Evening thunder, shall back me up!

It was Buoy 62023.

Duff data then.
Xcweather's wind history for that buoy shows 37mph at 1pm, which is more like it.

[William Grimsley]

4 minutes ago, Mapantz said:

Duff data then.
Xcweather's wind history for that buoy shows 37mph at 1pm, which is more like it.

I doubt it, seems reasonable out to sea.

Sun breaking through now, UKWW forecast still going for the risk of funnel clouds and low risk of lightning later on this afternoon, not much time left though.

Edited June 28, 2016 by William Grimsley

[Mapantz]

Just now, William Grimsley said:

I doubt it, seems reasonable out to sea.

Sun breaking through now, UKWW forecast still going for the risk of funnel clouds and low risk of lightning later on this afternoon, not much time left though.

lol reasonable? No other station is recording anywhere close to that, apart from where you'd expect it, up a mountain.

[William Grimsley]

Wind turning towards the west now, expecting wind gusts to reach close to if not gale force by the end of the evening.

Thunderstorms in SW Wales...

Edited June 28, 2016 by William Grimsley

[vladthemert]

crazy rainfalls in last 20 mins here in the area rain today.  Looking like 70 mm registered on the live radar I thought my weather station was playing up the road was like a river for short spell as trundled down the hill. amazing only time saw that was few years back when it rained for more spell closed roads of in all over Grimsby.

[weather09]

7 hours ago, Greeny said:

I think a good example of high PWAT keeping lightning to less than expected was here in Norfolk last thursday the 23rd. Although it was hot in the cloud breaks and was humid, DPs of around 20C, cloud cover kept the build up of CAPE to less than what was expected if clouds were not so in abundance.  Before it hit V4 radar realtime overlay stated 600j/kg of CAPE. The outcome were floods and some lightning with the odd loud cracks of thunder but lightning wasn't as frequent as it could have been if either CAPE was allowed to build up more or PWAT values were a bit less.

Edit: this was within the period where there was strong DLS in the mix.

Yes, last Thursday had plenty of moisture but relatively low instability, which meant torrential downpours but with lightning amounts not having been that high. Had the skies been clearer and temperature a good few degrees higher, no doubt CAPE would have responded and we would've seen an increased likelihood of severe storms.  Agree the amount of moisture in the atmosphere that day would have had a negative effect of updraft strength given the lack of heating and build-up of CAPE, but point is in an environment of moderate/high CAPE, you could have PWAT values of 4-5cm but that wouldn't be considered an inhibitive factor for storm development. Would just tell us that there's a lot of moisture in the atmosphere. 

Agreed with Nick F when he mentioned that the more southwesterly sourced component to the low-level flow at the time perhaps the reason why it was too cloudy/murky, where a more southerly/southeasterly flow off the continent would have seen more in the way of clear skies. 

[East_England_Stormchaser91]

Long live the 28th June. Not this year I'm afraid though!! 

Nothing promising on the horizon either.. 

[Greeny]

1 hour ago, weather09 said:

Yes, last Thursday had plenty of moisture but relatively low instability, which meant torrential downpours but with lightning amounts not having been that high. Had the skies been clearer and temperature a good few degrees higher, no doubt CAPE would have responded and we would've seen an increased likelihood of severe storms.  Agree the amount of moisture in the atmosphere that day would have had a negative effect of updraft strength given the lack of heating and build-up of CAPE, but point is in an environment of moderate/high CAPE, you could have PWAT values of 4-5cm but that wouldn't be considered an inhibitive factor for storm development. Would just tell us that there's a lot of moisture in the atmosphere. 

Agreed with Nick F when he mentioned that the more southwesterly sourced component to the low-level flow at the time perhaps the reason why it was too cloudy/murky, where a more southerly/southeasterly flow off the continent would have seen more in the way of clear skies. 

Yeah it went off over the continent and thats the flow we really needed. Was severe imo but for excessive rainfall, it did cause quite a bit of difficulty. Certainly a member in my fb group said a friend or relative had flooding issues. I drove passed a car that had broken down and the next day delivered a car to a customer who had his car break down cause of the floods. More heating and CAPE would have had a different output, I should think HP would have still been likely but storm stuctures would have been a lot more impressive and hail a good size I reckon too.

Sorry I didn't respond earlier William I wasn't able to keep an eye on the thread. Was interested in the shear, deep and low layer shear would have like to have seen a bit more CAPE build up and a higher troposphere. In general was the event interesting and did it have some noteable events? Its harder to judge when I don't live there to see it.

[Greeny]

12 minutes ago, East_England_Stormchaser91 said:

Long live the 28th June. Not this year I'm afraid though!! 

Nothing promising on the horizon either.. 

You never know something may crop up as we head into July. Keep an eye on Friday, showing some signs of a convective day more the north Scotland and Ireland but its 3 days out and it could change. The low may end up being further south when it arrives you never know.

Edit: the jetstream a direct hit currently being forecast producing strong DLS.

Edited June 28, 2016 by Greeny

[William Grimsley]

51 minutes ago, Greeny said:

You never know something may crop up as we head into July. Keep an eye on Friday, showing some signs of a convective day more the north Scotland and Ireland but its 3 days out and it could change. The low may end up being further south when it arrives you never know.

Edit: the jetstream a direct hit currently being forecast producing strong DLS.

Interesting, didn't quite play out as you thought today, no convection whatsoever round here!

[Greeny]

25 minutes ago, William Grimsley said:

Interesting, didn't quite play out as you thought today, no convection whatsoever round here!

Could have been that it ended up further north in South Wales. Without reports whos to say.

Worth a mention...

http://www.eadt.co.uk/news/tornado_spotted_in_suffolk_1_4595992

[Greeny]

When looking at the latest run on GFS it had another downgrade and the small area of CAPE was further north

 

[Ben Sainsbury]

Thunderstorm Forecast for 29th June 2016: Slight Risk of Thunderstorms!

Fairly low risk as a result of low CAPE, though could see isolated stronger cell across England/Scotland border or over Peak District. Possible funnel cloud here too.

[vladthemert]

On 6/28/2016 at 12:05, Azazel said:

complex set-up today, so my map looks like a picasso painting but these are the areas I would go for.

 

 

Hats of for getting our region red square right on the east coast

[Azazel]

2 hours ago, vladthemert said:

Hats of for getting our region red square right on the east coast

Success! Thank you kind sir:)

 

Now watch me get the next one unforgivably wrong:p

[vladthemert]

They always say swings and round-abouts.  Then again you might be on a roll.  .

I dont know why it was bad seem according to ease we was going to miss it but seem to concentrate in our area.  

[Polar Maritime]

Some very heavy rain on its way here.

 

[William Grimsley]

48 minutes ago, Polar Maritime said:

Some very heavy rain on its way here.

 

WOW, nice catch! What was it like?

[Polar Maritime]

Heavy rain and still ongoing William.

[THE MISSFITS]

Hi all,

 I live in Marlow and thought I would share this short video with you, sped up it shows convergence over Marlow, Buckinghamshire. However I am most disappointed that only a few very distant rumbles of thunder had our names on them this year...

 

Comments are most welcome!

Edited June 29, 2016 by THE MISSFITS

[Mapantz]

10 minutes ago, THE MISSFITS said:

Comments are most welcome!

HTML code doesn't work on here, you just need to paste the link and the forum software will embed it for you.

[THE MISSFITS]

20 minutes ago, Mapantz said:

HTML code doesn't work on here, you just need to paste the link and the forum software will embed it for you.

Thanks for the help, I had forgotten that it only needs the link..

[Greeny]

Friday looks like the north, Ireland and Scotland will be most at risk but Saturday GFS forecasting more widespread convection at the moment. (I'm going to say it :)) "a tongue" of cold air aloft overspeads the UK on both days.

[William Grimsley]

On 6/29/2016 at 20:33, THE MISSFITS said:

Hi all,

 I live in Marlow and thought I would share this short video with you, sped up it shows convergence over Marlow, Buckinghamshire. However I am most disappointed that only a few very distant rumbles of thunder had our names on them this year...

 

Comments are most welcome!

Nice video, was only up there last month!

[Summer Sun]

Day 2 Convective Outlook

VALID 06:00 UTC Fri 01 Jul 2016 - 05:59 UTC Sat 02 Jul 2016

ISSUED 20:33 UTC Thu 30 Jun 2016

ISSUED BY: Dan

Broad upper trough sharpens as it crosses the British Isles on Friday, with cold air aloft steepening lapse rates in response to diurnal heating. Expect scattered showers to form widely through the day, extending in coverage southwards and eastwards with time, with a few thunderstorms also likely. Best instability will be found across parts of Scotland, Northern Ireland and Ireland (a few hundred Jkg-1 MLCAPE), but here shear will be weaker. A better overlap of marginal instability and strong DLS (40-60kts) should be present across north Wales / north Midlands / northern + eastern England, and so here better organisation of cells seems likely.

The most intense cells could produce hail up to 2.0cm in diameter and strong, gusty winds.

http://www.convectiveweather.co.uk/forecast.php?date=2016-07-01