Storms and Convective discussion - 1st August 2022 onwards

[Nick F]

Seasonally warm SSTs and increasingly cold air moving in aloft with encroaching upper trough means steep lapse rates / plenty of CAPE lapping onshore from the English Channel / western coasts today - which will support plenty of heavy of heavy showers and thunderstorms across southern half of Britain and southern Ireland.

Lightning Wizard GFS derived charts show plenty of low-level shear too, with significant tornado parameters highlighted over southern England, along with strong convective gust risk ...

My storm forecast for today highlights severe risk along south coast:

THUNDERSTORM WATCH - TUES 01 NOV 2022

Issued 2022-11-01 08:23:19
Valid: 01/11/2022 0600 - 02/11/2022 0600

Forecast Details

Longwave upper trough over the N Atlantic will make further inroads across the UK and NW Europe on Tuesday, with a number of shortwave troughs rotating around the upper trough. One trough clears NE out over the North Sea this morning, taking away showery rain along associated frontal system with it. Following will be a strong moist surface SWly flow which will become unstable – as increasingly cool arrives aloft with upper trough moving in from the west. The instability will be enhanced by seasonally warm SSTs around southern and western coasts, with up to 1000 j/kg CAPE forecast over the English Channel, thanks to SSTs creating steep lapse rates with cooling air aloft, with CAPE tending to build inland across southern Britain downwind. This instability will support scattered heavy showers and thunderstorms – which will quickly spread NE across England, Wales and S Ireland. Across the UK, the risk of thunderstorms mainly south of a line from the Mersey to the Humber, greatest risk towards English Channel coasts, though isolated lightning possible in heavier showers around coasts further north across Ireland, N.Ireland, NW England and western Scotland.

Models show some fairly strong deep-layer shear across southern Britain, with the left exit of a strong jet streak aloft and flow veering towards the surface with passage of cold front clearing east this morning then post-frontal trough following from the west. So some organisation of storms into line clusters along the front and trough following are possible, with isolated 50-60mph convective gusts possible along southern coasts. A tornado or two can’t be ruled out either with stronger more buoyant updrafts near over English Channel that rotate where surface winds temporarily back / veer increases with height ahead of cold front and post-frontal trough. So a severe risk has been delineated for English Channel and immediate coastal areas. Heavy showers and thunderstorms may also produce hail and flash-flooding. 

Issued by: Nick Finnis

 

[Freeze]

Just had the heaviest rain I've ever seen lasted about 5 minutes, my road is underwater. Very surprised there was no lightning. 

[Guest]

Some lovely thunderstorms coming into Dorset currently. Any breaks in that line could be ripe for a tornado 

[CoventryWeather]

Had a few rumbles here in Coventry from a heavy downpour just now.

[Dreckly]

Thunder mixed in with the heavy showers coming in to Cornwall now. 

[Mapantz]

Thunder & lightning here, with a very close CG and explosive bang.

[Guest]

Loud thunder at work in Bournemouth 

[viking_smb]

1 minute ago, Alderc said:

Loud thunder at work in Bournemouth 

its from that squall line just passing you guys now. would be interesting to be afloat now in weymouth.... 

[Mapantz]

About 1.5 miles, as the crow flies..

[amybonnie98]

Quite a few loud rumbles of thunder in Southampton though can’t see anything on the radar at the moment 

[Mapantz]

You can see how angry that line was, no it's moving away:

Wareham Weather - Weather Cam

WAREHAMWX.CO.UK

---

Live RTSP webcam feed of the sky, pointed toward Poole and Bournemouth, using a Reolink 511WA IP Camera

 

[matt111]

Had a couple of rumbles over the last 15 minutes or so along with heavy rain  and a bit of hail. 

[James86]

Absolutely huge strike overhead on Hedge End! Rain is ridiculous!

[TropicThunder]

In Southampton just got caught outside in torrential rain thunder and lightning, soaked but enjoyed it! 

[Liam Burge]

TORRO has issued a Tornado watch, with some very 'concerning' wording for our neck of the woods.

[Tamsin]

Big squally thing is coming to Southeast London x

 

Edited November 1, 2022 by Tamsin
More pic

[Sprites]

Quite intense precip around Stevenage recently, can see anvil streaming away north 

[Mesoscale]

Thunder and hail with insane winds just blew through watford about 20 minutes ago! It was wild. 

[minus10]

Had a few flashes and rumbles with some heavy rain still going and some hail and gusty winds. Managed to get 2 gardening jobs done this morning when in the sunshine it felt really warm again...trouble is i am now comparing these thundery showers with that mega storm last sunday week ...nothing like that...spoit on that day...

[viking_smb]

very unusual for dan not to do a forecast

[*Stormforce~beka*]

4 hours ago, ResonantChannelThunder said:

Well, that was a wild night. Not quite as loud as storm Eunice, but given that was a daytime storm, this was definitely the loudest night of winds I've heard since moving out here in June 2021

What made you move to the IOW?

[ChannelThunder]

14 minutes ago, viking_smb said:

very unusual for dan not to do a forecast

From CW's Facebook, where they also shared TORRO's outlook along with this post:

"Sadly, being a voluntary organisation, no time to issue convective forecasts at the moment but TORRO have flagged the squally showers/thunderstorms today with potential for isolated tornadoes and large hail"

 

Edited November 1, 2022 by ResonantChannelThunder

[Eagle Eye]

Scuddy stuff already here as the initial parts of the squall line look to be approaching here.

[ChannelThunder]

8 minutes ago, *Stormforce~beka* said:

What made you move to the IOW?

I was born here and lived here until 2014, but moved off for 7 years while my girlfriend was doing Uni/PhD for the combination of better job opportunities and not having to put up with a long distance relationship anymore. Now, thanks to 'hybrid working' post-pandemic, we are back here, engaged and own a house!

[Eagle Eye]

Very interesting structure on the cell approaching me. Base of the cell looks fantastic, doesn't show up well on camera though.