Convective Storm/Discussion thread - 02/09/16 onwards

[Costa Del Fal]

3 minutes ago, redphil57 said:

I think it is as stoped assoon as it hit land, no thunder for 10 mins

Indeed although the rain is still going strong. Really quite torrential at times here.

Edited October 15, 2016 by Costa Del Fal

[Thunderstruck]

20 minutes ago, Nick F said:

Storm & Convective Forecast

Issued 2016-10-15 10:22:26

Valid: 15/10/2016 0600 to 16/10/2016

CONVECTIVE / STORM FORECAST - SAT 15TH OCT 2016

Synopsis

Upper and colocated surface will low in the southwest approaches will drift slowly NE across southern Ireland by early Sunday. Associated cold front will lift north across the UK and Ireland during Saturday, clearing N Scotland by midnight. Shortwave trough ejecting NE ahead of upper low and associated frontal wave will bring an area of squally heavy thundery downpours NE across southern England, Midlands, E Anglia and Wales this afternoon and evening, followed by further showers towards southern and western coasts of England, Wales and EIRE overnight that could be thundery.

... S ENGLAND, WALES, MIDLANDS, E ENGLAND AND IRELAND ...

Cold front lifting north brought a line of heavy rain and isoated thunder earlier this morning across far SW England, SW Wales and southern Irish Sea. Now Water Vapour imagery, 500mb relative humidity and vorticity charts indicate a marked shortwave trough moving NE towards SW England this morning - stronger lift and dry mid-level air of the shortwave is supporting an area of heavy convective rainfall with embedded isolated thunder and lightning now moving in across Cornwall and Brittany. This area of heavy rain with isolated thunder will continue NE across S England, Wales, Midlands and E England through the afternoon and evening. Strong southwesterly flow aloft and deep layer shear in the order of 30-40 knots will  be sufficient for organisation of convection/storms - with a risk of heavy rainfall leading to localised flooding and isolated strong wind gusts possible. Have issued a MARGINAL risk for localised flooding towards S England - where higher rainfall signal is indicated.

Further heavy showers will follow this convective/thundery area of rainfall from the southwest to affect southern and western coastal areas of England, Wales and EIRE this evening and overnight, as steep lapse rates overspread southern and western areas. Some heavier showers producing isolated lightning towards coasts where warm SSTs create stronger updrafts/high cloud tops through cold air aloft. Isolated localised flooding, hail and gusty winds will be possible with these showers.

Issued by: Nick Finnis

OK, that has definitely changed...

[Summer Sun]

Day 1 Convective Outlook

VALID 06:00 UTC Sun 16 Oct 2016 - 05:59 UTC Mon 17 Oct 2016

ISSUED 08:16 UTC Sun 16 Oct 2016

ISSUED BY: Dan

Broad upper low over Ireland will drift northwards through Sunday, eventually merging with the trough south of Greenland by the end of Sunday night. Cold mid-levels, associated with this feature, atop warm SSTs will generate deep convection over seas initially, but this then feeding inland by steering winds. The main hazards will be small hail and gusty winds with the most intense cells - a tornado cannot be ruled out. However, some elements of shower-training increases the threat of local flash flooding, especially on windward coasts where showers are most frequent.

http://www.convectiveweather.co.uk/forecast.php?date=2016-10-16

[Convective]

Not a lot stopping the convection today. All the way to the ceiling, then flat...

[stevofunnelcl]

woohoo, nice loud clap of thunder, my first thunder of 2016

as the cell moves north-east away from here, every lightning strike is making the power fail for about 3 seconds

I'm so glad i invested in a UPS, so the computer, monitor, and modem stay up when the power fails

[samadamsuk]

Hey all,

Nice views from here in Cirencester - I can see the cell over southamptin and at the same time the showers over central wales!

[Chris.R]

Sferics in  The Irish Sea again, north of Holyhead. Seem to be moving east. Feels like they've been teasing me all week around there. 

[matt111]

On the way back from Southampton and can see occasional flashes to the west. 

[Grimers]

There are thunderstorms W and E of here.

Edited October 16, 2016 by Grimers

[Mapantz]

I've just had a cracking little downpour here, 2.8mm in three minutes - 101mm/hr rate.

[Grimers]

9 minutes ago, Mapantz said:

I've just had a cracking little downpour here, 2.8mm in three minutes - 101mm/hr rate.

Yes, I watched it on your webcam, it was crazy!

Edited October 16, 2016 by Grimers

[Mapantz]

1 minute ago, Grimers said:

Yes, I watched it on your webcam, it was crazy!

Holy crap - I just read that, then clicked my cam, and a huge flash of lightning lit up the shower that just passed.. Epic timing!

[Grimers]

1 minute ago, Mapantz said:

Holy crap - I just read that, then clicked my cam, and a huge flash of lightning lit up the shower that just passed.. Epic timing!

That's sick!

Edited October 16, 2016 by Grimers

[ThundersnowDays]

No thunder and barely any rain here but some great clouds to the east earlier.

[Mapantz]

..probably less than 10 miles North of me..

[Frosty hollows]

Band of showers roughly aligned with the A 34 getting organised. Funny, I've just driven back from Plymouth and the only remarkable thing I saw was the moon rise over Swindon! Not a cloud in sight, so was quite surprised to hear the rain just after I got in

[Summer Sun]

Day 2 Convective Outlook

VALID 06:00 UTC Mon 17 Oct 2016 - 05:59 UTC Tue 18 Oct 2016

ISSUED 19:59 UTC Sun 16 Oct 2016

ISSUED BY: Dan

Upper trough north of the British Isles will begin to relax away to the NE through Monday, allowing mid-levels to gradually warm from the SW with time, and therefore restricting the aerial extent for the potential of deep convection farther to the NE as the day progresses. Nonetheless, showers will continue to develop over relatively warm SSTs and feed inland on prevailing winds - a low-end SLGT has been issued where the steepest lapse rates/best instability is likely to be found during the morning hours in particular. Some small hail and gusty winds will be possible with the strongest cells.

Overnight, a new cut-off upper low will break away from the main trough and slide/extend southeastwards across the British Isles, steepening lapse rates once again in western areas. Therefore there may be an increase in steric activity over W/SW Scotland later on Monday night, although this remains questionable due to a messy mix of precipitation contained within the wrap-around occlusion.

http://www.convectiveweather.co.uk/forecast.php?date=2016-10-17

[Raidan]

I've had a look around and there doesn't seem to be any thundery activity around here yet keep seeing random bright flickers of something has me confused.

[Chris.R]

4 minutes ago, Raidan said:

I've had a look around and there doesn't seem to be any thundery activity around here yet keep seeing random bright flickers of something has me confused.

 Could it be the aurora? There is an amber alert currently. 

Edit:  there was an   Amber alert  before but activity seems to have dropped off now actually. 

Edited October 16, 2016 by Chris.R

[Raidan]

14 minutes ago, Chris.R said:

 Could it be the aurora? There is an amber alert currently. 

Edit:  there was an   Amber alert  before but activity seems to have dropped off now actually. 

Could be I've ruled out it being lightning if it isn't the aurora then I have know idea what it could be...just seen it then while typing. 

[Thunderstruck]

6 minutes ago, Raidan said:

Could be I've ruled out it being lightning if it isn't the aurora then I have know idea what it could be...just seen it then while typing. 

Sounds weird. How close are you to Bristol Airport? It could be aircraft descending through the clouds

[Raidan]

12 minutes ago, Jcweather said:

Sounds weird. How close are you to Bristol Airport? It could be aircraft descending through the clouds

Not far Jc I can see planes coming in but it's not that as it's clear here and it's not the flashes you see when a plane is coming through the clouds...These are bright flashes just like lightning yet there are no storms and its happening about every 5mins very weird. 

[March]

Storm just hitting! Wasn't expecting it! Impressive flashes. 

[SnowJoke]

Just now, March said:

Storm just hitting! Wasn't expecting it! Impressive flashes. 

Developed just to the SW of Milton Keynes and dropped loads of heavy rainfall, 5 or 6 really bright flashes of lightning and some cracks of very loud thunder. Wasn't expecting a storm either as it doesn't feel stormy and only 10'c outside, very odd.

[Wilxy]

Friend reporting a storm just out to sea on isle of wight!