Convective/Thunderstorm Discussion : Summer/Autumn 2021

Gonzo

I think the UK thunderstorm risk has decreased somewhat and limited to areas like London and Kent/Essex. I doubt there will be any thunderstorm activity for Wales/SW England.

Storm 10

Some storm over France heading to the UK lucky beggars, there are some great live stream cameras on Skyline should be interesting later tonight

Tyrone212

French met have an orange warning.

The stormy degradation continues over Brittany during this late afternoon, affecting in particular the Côtes d'Armor and Ille-et-Vilaine; this degradation is gradually spreading to the whole of Normandy. Thunderstorms shift to the sea at the end of the day.

Potentially violent phenomena, such as hail and wind gusts of the order of 70 to 80 km / h, are possible, as well as heavy stationary rains which can cause accumulations of the order of 50 liters per square meter at during this stormy episode.

A second stormy wave from Aquitaine touches Anjou and Touraine in the early evening. This rain-storm system will cross the whole of the Center-Val de Loire region and will also affect the east of the Pays de la Loire and the south of Normandy in the first part of the night. This system then shifts to the Paris region from the middle of the next night.

As it passes, violent phenomena are expected, such as hail and strong gusts of wind that can reach 90 km / h, or even locally 100 km / h.

Oneiric 3

Nice looking cell heading up towards SE England now, possibly hitting the Brighton region in the next couple of hours:



Live cam from there, though it looks as if visibilty is quite low there at the mo so hard to make out cloud structure.

https://www.skylinewebcams.com/en/webcam/united-kingdom/england/brighton/brighton-pier.html

Oscar Bravo

Very heavy rain in parts of the south of England now. Heathrow reporting towering cumulus on the metar

EGLL 161950Z AUTO 20009KT 9999 -RA //////TCU 23/18 Q1009 NOSIG

Oscar Bravo

Nice bolts showing up on here https://www.beaming.co.uk/hastings-coastal-webcam/

glightning

Can also see action here. But not great quality. Plenty of lightning though

https://www.rhdr.org.uk/live-station-cam/

spookwoman

https://twitter.com/EWE_UK/status/1405261078548856832?s=20

glightning

God, it would make you sick how explosively storms fire up over France and Southern England. Just look at those cells firing up over western France right now. Meanwhile we sit and watch sat images and radar for 24 solid hours during any plumes that supposedly should deliver for us watching for the tiniest bit of convection to get going and get some tiny firecracker that goes out before it even gets lit! Super frustrating

Oneiric 3

glightning wrote: »

God, it would make you sick how explosively storms fire up over France and Southern England. Just look at those cells firing up over western France right now. Meanwhile we sit and watch sat images and radar for 24 solid hours during any plumes that supposedly should deliver for us watching for the tiniest bit of convection to get going and get some tiny firecracker that goes out before it even gets lit! Super frustrating

Was expecting better for the UK to be honest. Looking at the lightning maps a few strikes in the far SE (east of London) but pretty lame by their standards to be honest. More opportunities for them overnight and over the weekend though.

Storm 10

Check out the Dover webcam on Skyline brilliant lightning can't post a link

forestgirl

Storm 10 wrote: »

Check out the Dover webcam on Skyline brilliant lightning can't post a link

Thanks for that,what a beautiful looking place and so much lightning

pauldry

Thunder and lightning in Madrid last night so its sourced all the way down there.

We may get some before Junes out

Storm 10

See a few mentions of Thunder on ME Forecast for the week end , any updates on where this might happen.

glightning

Good storm ongoing in Augsburg, Germany right now

https://www.wetter.com/hd-live-webcams/deutschland/augsburg-old-town/5295e07add0f7/

Meteorite58

Some sever weather in the UK yesterday with possible Tornadic activity. Rain gauge near Solihull showing 30mm of rain in an hour and and a half.

https://twitter.com/PaulKnightley/status/1408515363835453442?s=20


https://twitter.com/haar_1s/status/1408509843158310922?s=20


https://twitter.com/convectivewx/status/1408515352821219341?s=20





https://twitter.com/UKWX_/status/1408516090502729731?s=20

Watch the wheelie and chair being lifted into the sky!


https://twitter.com/ArsenalSouvlaki/status/1408584840262344706?s=20


https://twitter.com/Petagna/status/1408548376547897352?s=20

Meteorite58

Some interest this weekend for convective weather with a chance of some heavy localized rain and some thunderstorm potential. Slow approaching Lp well off our W feeding in frontal bands and troughs , slowly rotating upper low. Temp quite warm in Munster on Sat with a high Dp and again Sun DP quite high and temps
probably getting up into the high teens or around 20C in places. High Theta E readings, not much deep layer shear but good low level convergence a possibility.

Meteorite58

Increasing potential again for Thunderstorm activity on Saturday , maybe some isolated storms from early morning more so in Southern counties but increasing from the afternoon across the country when temps get going. The ECM KO index is showing a decent potential, high Theta E readings, some high Dp's showing up , as much as 17C .

Soundings showing some very heavy localized rain possible . Warm and humid and probably feeling quite muggy.

Could easily have a yellow warning with this I would think but as always hard to pin point where would get the heaviest downpours, some well defined convergence zones showing up and topography playing its part aiding lift, slow moving systems so some places could get a right drenching even leading to spot flooding whilst areas even close by could have minor rainfall.

Also potential for Sunday.

Gonzo

GFS also showing some thunderstorm potential on Saturday over the south-west and into midland areas on Saturday afternoon/evening.



WRF also shows potential but this model often goes overboard with it which was the case last summer.



Arpege going for some thundery potential as well.

Meteorite58

Hi Res model AROME showing decent CAPE value's tomorrow. Convergence most evident in Clare / Connaught and the midlands, probably favour that area to peak in the afternoon tomorrow but anywhere could get the chance of an isolated storm tomorrow apart from the N which looks to be a low risk.

Meteorite58

ECM showing some small chance of a few sferics along Southern coasts later tonight and in the early morning.

Showing a lot of energy building in Munster tomorrow morning leading to some heavy rain and possible thunderstorms breaking out late morning/ early afternoon as the occluded front moves up the country. Showing a nice area of convergence around Limerick / Clare from the early afternoon , I wonder will this have a bearing on the amount of activity / heavy rain for there . Showing widespread potential as the chart below highlights .

Soundings for near Limerick at 13.00

Kermit.de.frog

Decent risk of storms and intense downpours Sunday and the east is in play. North Leinster and North Connaught most at risk. Should be interesting.

pad199207

Day 1 Convective Outlook
VALID 06:00 UTC Sat 03 Jul 2021 - 05:59 UTC Sun 04 Jul 2021

ISSUED 07:22 UTC Sat 03 Jul 2021

ISSUED BY: Chris/Dan

Broad upper trough will extend from the North Atlantic across the UK/Ireland on Saturday, to the north of the main jet activity which will run across Iberia and the Mediterranean. The subsequent cooling aloft atop a moist boundary layer (dewpoints of 14-17C, locally higher in East Anglia) will create a widely unstable environment in many areas, with the potential for deep convection and scattered showers/thunderstorms in numerous places.

Initially in the morning a PVA lobe will lift northwards across England and Wales, creating broad ascent with showery outbreaks of rain - with the potential for embedded convection to enhance rainfall intensity. As this early rain clears, increasing insolation and surface heating will help yield as much as 1,000 J/kg MLCAPE in places with forecast profiles revealing an incremental decrease in RH with height. For the most part, winds will be fairly unidirectional with height with only a slight increase in speed - the net result is fairly weak shear (generally 10-15kts), however stronger upper-level flow over eastern England could aid in better organisation/longevity of cells here with a greater potential for marginally-severe hail and perhaps an isolated tornado, especially where vorticity stretching occurs as updrafts move over existing low-level convergence. Particular focus on Norfolk and perhaps Lincolnshire.

In general, the slow storm motion coupled with any backbuilding could result in local flash flooding - this appears greatest over Devon and Somerset where a persistent convergence zone aligned near-parallel with the steering flow could result in multiple cells running over similar areas, giving locally very high rainfall totals. As a result a SVR has been introduced for the heightened threat of flash flooding, especially given the terrain and catchment response in the area.

A gradual weakening trend is likely through the mid-late evening, however PVA lifting north across northern England and southern Scotland may continue to aid development here for a time into the night hours. Otherwise, the main focus during the overnight period turns once again to the English Channel (and eventually southern England) as another PVA lobe encourages broad lift and areas of showery rain to develop - and again there will be the risk of a few isolated lightning strikes given weak/skinny CAPE.

pad199207

Status: Yellow
Risk of scattered thunderstorms this afternoon and evening, with risk of hail and spot flooding.
Status Yellow - Thunderstorm warning for Cavan, Clare, Limerick, Tipperary, Galway, Leitrim, Roscommon, Kildare, Kilkenny, Laois, Longford, Meath, Offaly, Westmeath

Met Éireann Weather Warning

Risk of scattered thunderstorms this afternoon and evening, with risk of hail and spot flooding.

Valid: 14:00 Saturday 03/07/2021 to 22:00 Saturday 03/07/2021

Issued: 11:55 Saturday 03/07/2021

Jpmarn

Some heavy downpours near Limerick city at around 12.30 this afternoon. Didn’t hear any thunder.

Tyrone212

Thunderstorm warning for the North Sunday

Heavy showers and thunderstorms are expected to break out from late morning on Sunday, perhaps becoming quite widespread during the afternoon. Some places will miss the worst of these, but where they do occur, 20 to 30 mm rain could fall in a short space of time leading to some surface water flooding. Lightning and hail will be additional hazards. Showers and thunderstorms will only slowly ease during the evening and some could persist well into the night.

Meteorite58

Report of CB's from Shannon, showing up nicely on Sat , moving towards the midlands, can make out the converging winds

Sunshine getting through now here near Tralee, 19.1C, humid

Jimbob1977

Heavy rain in Limerick around 1.30pm.

No thunder or lightning to report yet

hbhook

Some long rumbles outside of Roscommon now in the distance.

Rikand

hbhook wrote: »

Some long rumbles outside of Roscommon now in the distance.

Yep, nice cell outside Athleague has since moved north east of Roscommon

Dank Janniels

Heard that loud long rumble from North East Galway. Wasnt near a window tho to see any sparks!

DVD-Lots

Long loud thunderclap here in Athlone just now, missed the light show unfortunately.

Rikand

Also missed the light show, but loads of long low rumbles away to the North of the town

Arturo Delgado

Couple of rumbles Westmeath Offaly border. We've had over 20mm of rain since midnight. Almost as much as the entire month of June already.

Donegal Ken

A grey mess out there today. Pour soup unfortunately

OldRio

Thunder and some heavy downpours in South Leitrim.

Meteorite58

Thunderstorm activity slow to get going today and less active as the models might have predicted , still some heavy rainfall recorded.

Meteorite58

Plenty of convective potential tomorrow with heavy rain again and perhaps more widespread in the Eastern half of the country especially N Leinster, Northern counties, N midlands. Thunderstorm potential there with temps getting up to the high teens or touching 20C, high Dp's up to 15 or 16C . Pronounced areas of convergence and some more Deep layer shear than today should help to fire up some more electrical activity I would think. Heavy showers getting going from early.

Meteorite58

AROME is interesting for the E tomorrow. Showing an area of convergence and some decent CAPE values. Will there be a shot of thunderstorm activity ?

Showing getting up to around 19 or 20C with Dp's as high as 16 or 17C

PukkaStukka

https://twitter.com/convectivewx/status/1411592604387581952?s=19

Meteorite58

Some high rainfall totals being predicted.

Kermit.de.frog

Should start registering some sparks soon. North midlands appears the prime location but east Leinster, some convergence along the coast here, and Ulster as well in with a shout particularly this evening.

Donegal Ken

Status Yellow - Thunderstorm warning for Cavan, Donegal, Monaghan, Leitrim, Louth
Met Éireann Weather Warning

Risk of scattered thunderstorms leading to spot flooding.

Valid: 13:42 Sunday 04/07/2021 to 20:00 Sunday 04/07/2021

Issued: 13:43 Sunday 04/07/2021

emo72

Any chance of a few sparks in dublin?

Trebor176

emo72 wrote: »

Any chance of a few sparks in dublin?

It's not forecast, so I'm doubtful.

Kermit.de.frog

emo72 wrote: »

Any chance of a few sparks in dublin?

If there is to be a thunderstorm it would be most likely later this evening as wind goes more off shore.

PukkaStukka

Major fire in Strabane purportedly caused by a lightning strike

https://www.belfastlive.co.uk/news/strabane-fire-live-updates-building-20968358

Meteorite58

Fair amount of thunderstorm activity today. A large CG strike recorded at 04.04pm in Strabane as described below on meteologix.com , a bit away from where the building was thought to have been struck , it was the closest CG recorded, I think they can be out a bit o the map, I believe I remember Slowblowin say a strike near him was out a bit as recorded on the map but the time was spot on to the second. Could have been another strike of course that was not recorded.






https://meteologix.com/ie/lightning/donegal/20210704-1505z.html

Lightning: Cloud to ground, Power: 65kA (Strong slammer), Date: 07/04/2021, Time: 04:04:07pm




Railway street where o Doherty's was thought to have been struck.




https://twitter.com/Met4CastUK/status/1411740967342850055?s=20

Donegal Ken

Currently investigating a possible tornado or waterspout in Donegal/Derry.

Donegal Ken

Here is a photo just send on to me

https://twitter.com/DonegalWeatherC/status/1411790242626015233/photo/1