Storms and Convective discussion - June 2023

[Ryan H]

I saw a dark cloud coming towards my location and I seen the shelf cloud during my walks with the English bulldog.

[Supacell]

2 hours ago, Eagle Eye said:

Where are you positioned?

I was positioned just a couple of miles southeast of Scarborough. Probably a bit late for the answer now though

[WeatherArc]

Nice satellite view this evening, still a few agitated cumulus around though development chances likely decreasing as we lose surface heating.

[East_England_Stormchaser91]

As I said! A too fast moving setup for this country. Saw many cells explode up and mature off by the time they left the country. A shame, but not expected. 

[Harsh Climate]

3 minutes ago, East_England_Stormchaser91 said:

As I said! A too fast moving setup for this country. Saw many cells explode up and mature off by the time they left the country. A shame, but not expected. 

Let's be honest even those storms out in the north sea are nothing special. Very poor lightning output today from almost every storm..

Crazy how sometimes they are 60+/minute, then today 1-10/minute..

[I remember Atlantic 252]

20 minutes ago, WeatherArc said:

Nice satellite view this evening, still a few agitated cumulus around though development chances likely decreasing as we lose surface heating.

can see cumulus tops to my north

[Had Worse]

That will be the storm that went from nothing to a torrential thundery cell over me in 30 minutes 

[Harsh Climate]

43 minutes ago, East_England_Stormchaser91 said:

As I said! A too fast moving setup for this country. Saw many cells explode up and mature off by the time they left the country. A shame, but not expected. 

Bang on, despite seeing some rapid convection and very threatening looking skies it all just shifted away far too quickly for anything severe to develop. 

I've noticed recently as well on net weather radar, no sign on hail anywhere! Used  to be lots of brown on rain/hail/snow radar with lots of lightening in some storms. Maybe the lack of hail, less friction is why we are seeing less lightening?

Edited June 25, 2023 by Harsh Climate

[SarahWxm]

What a beautiful cloud at sunset tonight. It’s my late dads birthday today so I think it’s a fitting tribute for him  

[Derbyshire_snow]

Looks like something is forming here on North East Derbyshire border just gone out in the garden winds picked up and clouding over and gone dark to my south West. 

 

Scrap that it died  out as quickly as it formed disappointing day here. 

Edited June 25, 2023 by Derbyshire_snow

[Joey.GII]

Had a relatively successful chase up to the Yorkshire wolds ending up near Bridlington. As others have said not much visible lightning mostly just flashes but a couple of cgs. Also saw the roll cloud that @Aiden2012 posted earlier, I think this must have been associated with the cold front passage as it coincided with the renewed activity on the southern end of the storms. Just as I thought the day was done new cells fired all around and I'm certain a couple were briefly LP supercells, there was a CG from a fairly innocuous looking cloud that didn't appear to have much precip from it at all. Ended up getting in front of that last big cell near Bridlington. Overall successful but perhaps not entirely satisfying

First storm taken near M18/M180 junction

LP supercell, it perhaps just a very organised linear cell?! I know it doesn't look it but there was a CG from this in the right hand side of the image, very separate updraft and downdraft

 

Tail end cell as it was approaching driffield. Taken from the north. Would have loved to have been to the SE of it seeing that radar animation of it splitting. Storms had been racing north from me all afternoon so I thought I was right in its path untill it sent it straight east

Finally a lone sheared updraft, can't recall ever seeing things like this in the UK, there were a few around today!

[Supacell]

@Joey.GII We were probably driving back at the same time, on the same roads .

Nice account and I second your thoughts. A successful day's chasing but not as good as I'd hoped. Today had the makings of a memorable day, but it was not to be. But there were plenty of storms and where they were expected to be so I'm happy enough.

[WeatherArc]

Just going over some soundings from today, this is from the 06z GFS at about the same time those potential supercells were ongoing near York

Very interesting profile, reveals why todays event may of been less potent than what was forecast.

As i suspected-large temp/dewpoint spread, favouring more elevated storms with higher bases and lessening any potential tor threat.

Distinct lack of lightning in storms, suspect it was due to some pretty bad mid and upper lapse rates this may also be why storms were struggling to gain any height.

Good hodograph though, can see why supercells developed. Not much SRH though probably why the wall cloud that was spotted near York was struggling. EBWD near 40 kts though so would still favour supercells. 

Despite this event not being what it could of been i have the feeling that this is a setup we will see again this year, storm seasons only just begun 

 

 

[MikeUpjohn]

Sounds like we were all very close to one another. I left Macclesfield for Sutton Bank at 12.30pm convinced it was too late and we'd miss everything and be driving into the back of the cells moving away, but made good time over the M62 and were in position on Sutton Bank for 3pm, just as those storms started to go up.

Moved East to Pickering and then South, stepping down the cells, but ultimately got left with blue skies as it headed out to sea over Whitby and Scarborough way. Some definite brief supercell structures in there and a brief loosely organised wall cloud a couple of times, but couldn't get a picture as was driving. The final storm chucked out a couple of huge C-G gunshot thunders near Stamford Bridge.

Back home for 8.30pm and a great day of chasing in England.

Mike.

[Aiden2012]

Already a better start to convection today

[ChannelThunder]

Wednesday night's cold front has caught my eye (probably out of storm-starved desperation more than anything!)

A few cherry-picked crumbs to go by on the models:

 

 

[Southern Storm]

2 hours ago, ChannelThunder said:

Wednesday night's cold front has caught my eye (probably out of storm-starved desperation more than anything!)

A few cherry-picked crumbs to go by on the models:

 

 

It's nice to have something to pin our hopes on at least even if it doesn't come to anything, also I get feeling this season is going to throw up some real surprises.

[Windblade]

Nowt here since last Tuesday, just boiling hot sun. 32c yesterday. 

[Eagle Eye]

No forecast today as Jay forgot and I'm not writing a discussion for at best a low end slight risk for us. That's why we're not the professionals .

Edited June 26, 2023 by Eagle Eye

[Richard Taylor]

Thunder/lightning at Aberdeen.  

 

[howham]

4 minutes ago, Richard Taylor said:

Thunder/lightning at Aberdeen.  

 

Confirmed Bridge of Don.

[mike57]

We had a single rumble of thunder during a heavy shower this morning, there may have been more but I was inside. Been fine since then.

[Eagle Eye]

15 hours ago, WeatherArc said:

 

Good hodograph though, can see why supercells developed. Not much SRH though probably why the wall cloud that was spotted near York was struggling. EBWD near 40 kts though so would still favour supercells.

 

A few things to note;

1) A lot can hide in SRH, only use it if you're in a place without a sounding with a hodo available. Low SRH bt a large strewamwise vorticity current (so low but directional inflow) is much more likely than a large crosswise inflow layer (which has larger SRH) to produce a tornado. However, that theoretical crosswise would produce decent hail versus the large streamwise. However, that is because of the inflow layer, do not use vorticity to forecast hail. Updraft speed vs hail fall speed is a good idea to use. Updraft speed is calculated by doubling the CAPE then square rooting it. Then you can find a document online from one of the many with hail falling speed versus hail size. Do remember to factor in drag from wind and how big the inflow layer actually is.

2) To work out tornado formation versus wall cloud sitting I typically use a couple different things.

The lifted condensation level (LCL), streamwiseness of vorticity and the wind flow (I'll explain later). 3cape Is useful in certain situations as well.

LCL - A high LCL will mean that there is just a lot more shearing, vorticity and general energy needed to touch down. Even with very good background signals, there's very little you can do to counteract a high LCL.

Streamwise vorticity - First we have to understand what it is. Vorticity is the rolling in the atmosphere created by change of wind with height. The vector of the vorticity is perpendicular to the left of the shear vector (Cameron Nixon says).

The streamwiseness of vorticity. When the storm relative wind goes through the vorticity rather than across it, it 'induces' that SVC which increases tornadic potential. Look below for the through vs across.

Here's what I mean with SRH not always being a good idea.

Important to note that if crosswise vorticity has enough time it should be able to do what the streamwise vorticity could as well. Strong crosswise vorticity can help with anticipating a split along with the left mover and right mover bunkers. Which could help induce enough streamwiseness further along the line.

That's where parcel directed by wind flow comes in handy.

If the storm motion is parallel to the flow, then the storm will stay in the crosswise flow for long enough for enough strewamwiseness to build up. You only need to worry about that in crosswise vorticity situations. The more perpendicular to the flow, the less of that strewamwise can be built up.

 

Yesterday there were fairly high LCL's and it spears that the vorticity was fairly crosswise. Though storms stayed fairly parallel to the flow, the LCL and the vorticity angle meant that storms found it hard to get beyond the wall cloud stage I suspect.

 

If anyone wants to understand anything just ask, I've done my GCSE's and so have lots of free time now all of a sudden.

Edited June 26, 2023 by Eagle Eye

[WeatherArc]

27 minutes ago, Eagle Eye said:

A few things to note;

1) A lot can hide in SRH, only use it if you're in a place without a sounding with a hodo available. Low SRH bt a large strewamwise vorticity current (so low but directional inflow) is much more likely than a large crosswise inflow layer (which has larger SRH) to produce a tornado. However, that theoretical crosswise would produce decent hail versus the large streamwise. However, that is because of the inflow layer, do not use vorticity to forecast hail. Updraft speed vs hail fall speed is a good idea to use. Updraft speed is calculated by doubling the CAPE then square rooting it. Then you can find a document online from one of the many with hail falling speed versus hail size. Do remember to factor in drag from wind and how big the inflow layer actually is.

2) To work out tornado formation versus wall cloud sitting I typically use a couple different things.

The lifted condensation level (LCL), streamwiseness of vorticity and the wind flow (I'll explain later). 3cape Is useful in certain situations as well.

LCL - A high LCL will mean that there is just a lot more shearing, vorticity and general energy needed to touch down. Even with very good background signals, there's very little you can do to counteract a high LCL.

Streamwise vorticity - First we have to understand what it is. Vorticity is the rolling in the atmosphere created by change of wind with height. The vector of the vorticity is perpendicular to the left of the shear vector (Cameron Nixon says).

The streamwiseness of vorticity. When the storm relative wind goes through the vorticity rather than across it, it 'induces' that SVC which increases tornadic potential. Look below for the through vs across.

Here's what I mean with SRH not always being a good idea.

Important to note that if crosswise vorticity has enough time it should be able to do what the streamwise vorticity could as well. Strong crosswise vorticity can help with anticipating a split along with the left mover and right mover bunkers. Which could help induce enough streamwiseness further along the line.

That's where parcel directed by wind flow comes in handy.

If the storm motion is parallel to the flow, then the storm will stay in the crosswise flow for long enough for enough strewamwiseness to build up. You only need to worry about that in crosswise vorticity situations. The more perpendicular to the flow, the less of that strewamwise can be built up.

 

Yesterday there were fairly high LCL's and it spears that the vorticity was fairly crosswise. Though storms stayed fairly parallel to the flow, the LCL and the vorticity angle meant that storms found it hard to get beyond the wall cloud stage I suspect.

 

If anyone wants to understand anything just ask, I've done my GCSE's and so have lots of free time now all of a sudden.

Wow thanks, this is some rlly interesting stuff. Ive always struggled with streamwise/crosswise vorticity i know what they do/are but can never figure out how to spot it in a hodograph. That storm relative hodograph paper by Cameron Nixon is useful though, i've read through it a couple of times and its very helpful with working out things such as storm motion, large hail vs tor potential, deviant tor motion etc.

I just wish we could of had the cape of last week, lower LCLs and a bit more backing/veering of the low level winds but hopefully we can get a round two sometime mid-july.

Good luck with your results btw, i did mine last year so slightly jealous of you guys getting 2 months off 

[Supacell]

Footage of the heavy showers and thunderstorms I saw and chased back on Thursday (June 22nd). Only just managed to get it edited and uploaded as was obviously out chasing all day yesterday. The footage from yesterday will be ready later in the week I expect.