Storms and Convective discussion - September 2023

[Metwatch]

Some more captures from Chailey, he mentioned that the second bout of storms in the wash was a CG fest, with all but one visible strike hitting the ground! 

 

[alexisj9]

2 hours ago, Thomas Dicken said:

Here's some of my favourite captures from the 9th, including lightning hitting a tree opposite me.

 

 

My tree has been hit at some point, probably the banger from last year I said hit in my garden, I didn't realise it has scorch marks on it it till last week though, was looking where I need to cut it this autumn once the leaves fall.

[WeatherArc]

Next Sunday looks like it could be a decent day for thunderstorms for at least those in the Cotswolds/Wiltshire area, need to resolve problems with how high/how far north the temps and dewpoints go but looks decent at the moment.

Am noting the southerly/south easterly low level flow on the hodograph as well, could be another event where we actually have decent shear although its way too far out to really know right now.

 

Comparison between the GFS chart for yesterday and the 06z chart for next Sunday, relatively similar with the exception of the ridge in central Europe. 

 

[Emz by the Thames]

Quick question, my friend was on a hill watching a a very large and active thunder storm in the distance to the north west of High Wycombe at about 7.30/8pm last night. Which storm would that have been? Thank you!!

Would it have been the same one seen from the Salisbury are..i.e the mid Wales one?

Edited September 11, 2023 by Emz by the Thames

[WeatherArc]

3 minutes ago, Emz by the Thames said:

Quick question, my friend was on a hill watching a a very large and active thunder storm in the distance to the north west of High Wycombe at about 7.30/8pm last night. Which storm would that have been? Thank you!!

Most likely would of been that very active thunderstorm over Mid-Wales. 

Edited September 11, 2023 by WeatherArc

[wimblettben]

Pictures of the mid Wales storm before it got dark and I could see the lightning from it.

 

 

Probably one of the widest anvils I have ever seen.

[Flash bang flash bang etc]

Looking forward to looking forward to the possibility of storms somewhere down here. Yesterday looked like a stonker, but it’s happened now - let’s look at what’s to come and not dwell on the past lol

[Flash bang flash bang etc]

Speaking of the past here is yesterday’s full (sped-up) footage from the Peterborough cam

(the full thing was 1.5gb!)

 

 

[Supacell]

4 hours ago, minus10 said:

As you know i am not a chaser...however yesterday i was tempted to go up to Cambridgeshire way or even the Wash area/ Holbeach as it became apparent the storm meant business when it hit Milton Keynes.....however my family circumstances would not make it feasible anyway. Therefore i rely on you guys and all the good work you do to capture those magnificent storms...obviously it doesnt always work out for you buts it incredible what you do...i couldnt do all that driving for one thing...keep up the good work if you can. It is much appreciated. ..i  just do chases from my front to back garden..sure the neighbours think i'm nuts..

 

Thank you. I expect people think I'm nuts too when they drive past me standing in the rain

[WeatherArc]

Not everyday you see British homegrown storms being exported to Norway! Very surprised they survived crossing the North sea. 

 

 

Yesterdays setup really reminded me of the 28th June 2012 supercells, maybe a little less potent but still very strong storms.

 

Edited September 11, 2023 by WeatherArc

[ChezWeather]

Would anyone be interested in a telegram channel for UK Storm Chasing? 

Probably only be used on active high risk days such as yesterday, but it'd certainly make it easier to share target locations etc. 

 

P.S Mods apologies if posting about external apps is against forum rules 

 

 

[Ben Sainsbury]

Quite frankly gutted I missed the cluster of severe thunderstorms over Lincolnshire/The Wash yesterday. I think I disregarded the risk too easily due to the flip-flopping nature of the models. 

[Mapantz]

Possible for some thunderstorms/showers in the SE tomorrow.

[Kirkcaldy Weather]

On 09/09/2023 at 16:02, Kirkcaldy Weather said:

SUPER high PWAT level incredible it's as anomalous as the PWAT within the TC across the Mediterranean

 

On 09/09/2023 at 16:02, Kirkcaldy Weather said:

Jet Streak of Ex Franklin causes the frontal wave to lift north 

A VERY VOLATILE parameter space evolves alongside this northward lift

 

I'm expectant the ECM will be pretty close to actuality 

• Cluster developing into Northern England which probabilities indicate matures to a violent MCS
• Window open along the boundary into Scotland for supercells firing 
• Cold Front doesn't get through the country until Wednesday 

 

I should implement my own risk criteria based within impacts I see happening 

Small Impact

Medium Impacts

Severe Impacts

️EXTREME Impacts️

SUNDAY 10TH SEPTEMBER 2023 - Severe Impacts

Very happy how this forecast unfolded especially considering the unique nature of it being a September Storm Event 

If I start at this section 

On 09/09/2023 at 16:02, Kirkcaldy Weather said:

• Cluster developing into Northern England which probabilities indicate matures to a violent MCS
• Window open along the boundary into Scotland for supercells firing 

 

This was nailed effectively as the radar animation shows the supercell & MCS did aquire right deviation 

Quite incredible just how close yesterday's setup connected with the famous 2012 event of June 28th

Now if I put the PWAT outlook and actual radar animations together it's another fantastic link with the zone of incredible PWAT measurements literally bang on where got the most severe conditions 

On 09/09/2023 at 16:02, Kirkcaldy Weather said:

Cluster developing into Northern England which probabilities indicate matures to a violent MCS

 

[Supacell]

12 hours ago, Zak M said:

Just uploaded Sunday's storm to YouTube. Couldn't see much lightning (apart from a +CG) but the thunder was like one constant roar. 

I could also see hailstones bouncing off my patio while reviewing the footage. Should've headed out to measure them...

Great video. With that constant thunder, imagine what it would have looked like at night.

[Supacell]

1 hour ago, Ben Sainsbury said:

Quite frankly gutted I missed the cluster of severe thunderstorms over Lincolnshire/The Wash yesterday. I think I disregarded the risk too easily due to the flip-flopping nature of the models. 

The latest Arome before I left for Yorkshire showed it too, however I dismissed it as it was totally different from its previous run which targeted Yorkshire.  Honestly, it seems every risk day has huge model uncertainty. Even more so over recent years. Or it could be that we have so much data available to us these days and its hard to guess which model has it right.

[cheese]

2 hours ago, WeatherArc said:

Not everyday you see British homegrown storms being exported to Norway! Very surprised they survived crossing the North sea. 

 

 

Yesterdays setup really reminded me of the 28th June 2012 supercells, maybe a little less potent but still very strong storms.

 

We were stuck in the middle on both occasions lol

[Flash bang flash bang etc]

2 hours ago, Flash bang flash bang etc said:

Speaking of the past here is yesterday’s full (sped-up) footage from the Peterborough cam

(the full thing was 1.5gb!)

 

 

What I like about this is it shows that an elevated storm during the day DOES have visible lightning but often it’s only really noticeable afterwards on video or through the photography. There was a huge amount of electrical activity in that storm but you probably see about 10% in the video

always worth considering this when planning to chase. Staring at torrential rain is fantastic but is it worth all the time and energy (and money) if you can’t see the lightning? Well that’s the important question

[Alderc 2.0]

2 hours ago, WeatherArc said:

Not everyday you see British homegrown storms being exported to Norway! Very surprised they survived crossing the North sea. 

 

 

Yesterdays setup really reminded me of the 28th June 2012 supercells, maybe a little less potent but still very strong storms.

 

Always amazes me how storms manage to cross hundreds of miles tepid North Sea however when they dip their toes in the channel of the north French coast it’s almost instant death! 

[Lt. Dan]

21 minutes ago, Supacell said:

The latest Arome before I left for Yorkshire showed it too, however I dismissed it as it was totally different from its previous run which targeted Yorkshire.  Honestly, it seems every risk day has huge model uncertainty. Even more so over recent years. Or it could be that we have so much data available to us these days and its hard to guess which model has it right.

I'd say we don't have enough data. Look at some of the convection allowing ensemble suites that are available for North America. We have a handful of deterministic CAMs to take a look at but they are limited in true value, I think. Especially for those that like to chase on a day like yesterday. I think there are also some misconceptions on how these models work, how many people realise that the WRF is not just one model? There are many flavours out there and most of them are initiated from the GFS, Netweather's NMM for example, Manunicast's WRF (very rarely gets mentioned here) or the WRF at modelzentrale.de, all with different physics. I'd love to have more data, but then I'm a storm/model junkie

[TJS1998Tom]

Pretty impressive skies atm. Shame nothing thundery today 

 

Edited September 11, 2023 by TJS1998Tom

[Metwatch]

17 minutes ago, DanN said:

I'd say we don't have enough data. Look at some of the convection allowing ensemble suites that are available for North America. We have a handful of deterministic CAMs to take a look at but they are limited in true value, I think. Especially for those that like to chase on a day like yesterday. I think there are also some misconceptions on how these models work, how many people realise that the WRF is not just one model? There are many flavours out there and most of them are initiated from the GFS, Netweather's NMM for example, Manunicast's WRF (very rarely gets mentioned here) or the WRF at modelzentrale.de, all with different physics. I'd love to have more data, but then I'm a storm/model junkie

I remember first coming across the modellzentrale site probably nearly 2 years ago now.

A huge array of parameters from one of the WRF ARW models, half of which I have little clue on what they mean. I do agree that more CAMs would be appreciated for this part of the world though.

[Flash bang flash bang etc]

 

not being funny but didn’t they just run all that way anyway?

[Flash bang flash bang etc]

13 hours ago, Zak M said:

Just uploaded Sunday's storm to YouTube. Couldn't see much lightning (apart from a +CG) but the thunder was like one constant roar. 

I could also see hailstones bouncing off my patio while reviewing the footage. Should've headed out to measure them...

Excellent video - I reckon it’s worth you investing in a boom mic, would have been amazing to get the pure thunder during the approach and the heaviest bits

[East_England_Stormchaser91]

40 minutes ago, Alderc 2.0 said:

Always amazes me how storms manage to cross hundreds of miles tepid North Sea however when they dip their toes in the channel of the north French coast it’s almost instant death! 

Different dynamics I would say. Afternoon surface based French stuff never does too well once it hits the channel. If there’s no mid level instability, the storm just simply loses all source of fuel. Yesterday there was plenty of ML CAPE as well as surface based CAPE to sustain them. Although they lost their intensity a tad once out in the North Sea.

Couldn’t believe how much lightning that mothership was pinging out. Lincolnshire yesterday was rivalling some of the severe storm outbreaks that France, Germany and BeNeLux see.