Storms and Convective discussion - 1st May 2022 onwards

[Frosty hollows]

55 minutes ago, Ben Sainsbury said:

Will be going chasing tomorrow, from my location in Bristol atm. Despite the westward corrections, I think I'm going to position myself maybe as far east as Brighton given past events. But maybe position closer to Portsmouth should developments happen further west. Does appear tonight to be a distinct split in the developing squall line/MCS, so the possibility of one system moving across CS England and the other much later in the night across the SE.

I've a hunch. Am staying home.

[Woodboss]

44 minutes ago, Flash bang flash bang etc said:

I’m looking at Ashdown Forest area, perhaps down towards Brighton (but trying to avoid light pollution and built-up areas) . Consider you’ll probably want to head NE to chase the storms a little once they pass - but they will be moving quickly.

Where I’ve been a few times now in Ashdown forest is really open in all directions and super quiet, too. Great place if the storms aren’t too far East

Ashdown forest is a good shout for sure,possibly Newlands corner just south of Guildford too as visuals there will be good too. Will be going to devil's dyke just north of Hove first to see how it pans out as visuals there are good for miles. 

[East_England_Stormchaser91]

Have to say it, the ingredients for this look pretty impressive apart from fairly modest CAPE values. Directional shear looks to be pretty impressive with Easterlies at the surface, very warm 850 temps on a SE’ly being overlapped by strong SW’lies above. Should make for some impressive hodographs. 
 

23:00 shows a very decent mix! 

[Mapantz]

No work tomorrow, so playing some Mario kart 8 on the switch, and thought I'd check the 21Z UKV out..

[TJS1998Tom]

15 minutes ago, Mapantz said:

No work tomorrow, so playing some Mario kart 8 on the switch, and thought I'd check the 21Z UKV out..

Now that certainly looks good for Lincoln. 

[Petorious]

4 hours ago, Mapantz said:

No work tomorrow, so playing some Mario kart 8 on the switch, and thought I'd check the 21Z UKV out..

Believe this when I see it ,  I do hope it comes off like that though.

[Ben Sainsbury]

UKV 0z still looking nuts, it’s such a relief to see that this is all still there and hasn’t disappeared overnight

[Guest]

Arome looks even further west this morning and actually has a second potential MCS moving into the SE during the early hours. 
 

Could be an interesting evening and overnight period with the usual, will it / will won’t anticipation being from about 6pm. 
 

[sheikhy]

Wow what an upgrade for the midlands!!!pretty much bullseye hit this evening!!will it happen like that though?!all down to radar watchin for me now!

[markw2680]

I have a feeling Birmingham is a bit to far north west for anything this evening but I live in hope, I’d say half way point between brum and London is the place to be

[sheikhy]

21 minutes ago, markw2680 said:

I have a feeling Birmingham is a bit to far north west for anything this evening but I live in hope, I’d say half way point between brum and London is the place to be

I think brummy eastwards are all in the game!!!as i say radar watchin is key!!

[The Tall Weatherman]

18 minutes ago, markw2680 said:

I have a feeling Birmingham is a bit to far north west for anything this evening but I live in hope, I’d say half way point between brum and London is the place to be

I live in the centre of those areas but I’m not sure Brum will get it. These MCSs always take an east shift at the last moment. Hopefully it is like Sunday night but further east and more active and the forecast soundings really highlight the possibility of  it being very active! Anyways I love your hope but let’s just wait and see.

[Eagle Eye]

Met4cast has a high risk for today

[Ben Sainsbury]

12 minutes ago, Eagle Eye said:

Met4cast has a high risk for today

Elevated thunderstorm events are notoriously hard to predict. The majority of the models do look impressive even for regions within our SLGT zone. We’re just uncertain on the NW extent of any lightning, so maybe we’ve been a little conservative with our forecast so we’ll have to see. The key thing to note is; it’s not that SE England/the Channel will see more lightning, it’s more of a case of this region just being at a higher risk of lightning.

Edited May 18, 2022 by Ben Sainsbury

[minus10]

Interesting storm forecast from Nick for today..

Severe Convective Weather & Storms Forecast - Netweather.tv

WWW.NETWEATHER.TV

 

[sheikhy]

A lot of the warning this morning have expanded much further north and west!!bodes well widely!!!

[ChannelThunder]

8 hours ago, biddie said:

It's not will be similar to past few nights

 

Huh?

[LoveStorms]

this is my first ever post after snooping for years.  I’ve always relied on these forums for the real weather forecasts (particularly when it comes to storms). I’m so excited for tonight.  I missed the brief passing of a storm on Sunday/Monday due to being asleep..  I have high hopes for this one actually hitting my area tonight

[Cableguy]

No Metoffice warnings as yet....time will tell.

[sunnijim]

Extremely muggy again this morning,the freshening of the air as the cold front past through last night very temporary.

Some good sunny spells breaking the low level cloud streaming off the channel.

The atmosphere on a non technical level 'feels right' for some fun and games this evening!

[sheikhy]

Slight shift east for my area on 03z ukv!!hopefully back west again on 06z!!

[Nick F]

SEVERE THUNDERSTORM WATCH - WEDS 18 MAY 2022

Issued 2022-05-18 06:32:22
Valid: 18/05/2022 0600 - 19/05/2022 0600

Forecast Details

SEVERE THUNDERSTORM WATCH FOR CS / SE ENGLAND, SE MIDLANDS, LINCS & E ANGLIA

• Large hail
• Wind gusts of 40-60mph
• Flash-flooding
• Frequent cloud-to-ground lightning

Discussion

Large longwave trough over the Atlantic continues to generally control the weather as we enter midweek. Although high pressure over the near continent has ridged back in to stabilise the atmosphere for most through much of today, another shortwave trough will eject NE towads SE UK later, while a cold front also arrives across the NW in the evening.

Meanwhile, a warm/moist plume of high theta-w values (14-16C) will return to SE UK this evening, in response to the flow backing ahead of aforementioned shortwave moving in from the SW. The nose of the high theta-w plume spreading north out of France will become increasing unstable later today on its NW edge over northern France and English Channel, as colder upper level air from Atlantic trough overruns from the SW creating steep mid-level lapse rates. MUCAPE values as high as 750 - 1000 j/kg across northern France in the afternoon may advect as far north as S England in the evening. This strong instability looks to be released to form clusters of elevated thunderstorms over Normandy and central English Channel areas this evening, as shortwave trough approaching from the SW engages plume and creates forced ascent of the warm moist airmass into colder air aloft. These thunderstorms look to expand and then spread NE across central S and SE England and East Anglia later in the evening before clearing eastern England over the North Sea in the early hours.

Theta-w and MUCAPE charts for 21z this evening:

 

Fairly strong SWly jet stream winds aloft while winds are backed SEly towards the surface is forecast to bring 40-50 knots of deep layer shear. This will favour storm organisation into bowing line segments and perhaps one or two supercell storm structures, these storm modes bringing with them a risk of isolated large hail, frequent cloud-to-ground lightning and wind gusts of 40-60mph. Eventually these storms merging into a linear MCS before clearing. With high PWAT values inherent of the high theta-w plume, there is also a risk of intense rainfall leading to flash-flooding and very hazardous driving conditions, though storm motion will be 30mph, so any flooding should be temporary. A Severe Risk area has been delineated for CS / SE England, SE Mids, Lincs and East Anglia for the hazards of large hail, strong wind gusts, frequent cloud-to-ground lightning and intense rainfall.

Upper winds and 0-6km shear for 21z:

Precipitable Water (PWAT)

T+24 fax chart from Met Office:

Elsewhere, cold front moving across Ireland early evening before moving across Scotland and NW England late evening / early hours will bring a brief line of convective rain, the odd lightning strike can't be ruled out, but generally convection too shallow. Post frontal airmass following across Ireland will have corridor of steep lapse rates for a time, which will support heavy showers late afternoon / early evening - with potential for some lightning and hail.

The range of models this evening:

Issued by: Nick Finnis

Edited May 18, 2022 by Nick F

[Azazel]

I'm hoping if anything fires to the south west of here, it's earlier than the usual time of 12-2am. Would be really nice to see some storm structure in daylight/evening hours.

[ChannelThunder]

A nice upgrade from Convective Weather a few moments ago, too!

[Harry]

Indeed @Lance M

Here is a link for those who might not be familiar:

Convective Weather

WWW.CONVECTIVEWEATHER.CO.UK

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Forecasting thunderstorms and severe convective weather across the British Isles and Ireland for up to the next 5 days.