Storms and Convective discussion - 10th April 2020 onwards

[Eagle Eye]

7 minutes ago, chionomaniac said:

I’ve seen a few storms today but no persistent rotating updrafts lol. So no supercells here but great storm structures today and wouldn’t rule out a brief funnel or two 

Saw one possibly earlier look at my possible funnell cloud video earlier

[Flash bang flash bang etc]

I can totally understand how easy it is to get overexcited in the heat of the moment and shout ‘Supercell!’ at everything

[Windblade]

5 minutes ago, Xanderp009 said:

Saw one possibly earlier look at my possible funnell cloud video earlier

I had a look at that was is only 2 seconds long? Couldn't really see anything on there but it is hard to see.

[Windblade]

4 minutes ago, Flash bang flash bang etc said:

I can totally understand how easy it is to get overexcited in the heat of the moment and shout ‘Supercell!’ at everything

Absolutely, although that's not to say we don't get the odd supercell here in the uk.

[Flash bang flash bang etc]

Just now, Windblade said:

Absolutely, although that's not to say we don't get the odd supercell here in the uk.

Judging by this thread sometimes I’d say we get approximately 20,000 a month  

[Windblade]

1 minute ago, Flash bang flash bang etc said:

Judging by this thread sometimes I’d say we get approximately 20,000 a month  

[Paul Sherman]

Yes we do get Supercells in the Uk and as another poster said how many low topped Supercells go unnoticed due to the lack of Doplar, remember Cold Core Supercells only really reach levels of 20-27k feet which is attainable by quite a few UK Storms in our Spring and Summer Months. 

Most Uk Single Cell Storms hang out at around 15-18k feet but we have had Storms above 40,000 feet before

[<<Ryan>>]

Occasional rumbles of thunder over the past 20 minutes along with some gusty winds.
Fingers crossed we don't have to wait too long for some big summer storms to come our way!

[Eagle Eye]

8 minutes ago, Windblade said:

I had a look at that was is only 2 seconds long? Couldn't really see anything on there but it is hard to see.

i''ll get you a longer one

[convector]

52 minutes ago, Thunder and Lightning said:

This storm is even looking a bit supercellular.

does indeed look like a low topped supercell or at least something with mild rotation - you can see it in the lightning trail - the movement is more southerly than surrounding cells

[Mitch the motorbike storm]

Nexthe cell is here

[Zak M]

Just seen a cauliflower to my NE

[Kirkcaldy Weather]

50 minutes ago, Paul Sherman said:

 Everythings a Supercell

You guys do know whats needed to actually make a Supercell ?? 

Seriously not everything is a supercell because it has a white core on radar

Yes exactly Paul the day that springs to mind though I tend to try forget as storms completely missed here was 28th June 2012 with the Sleaford tornado which indeed had supercell signature on radar, some of the hail producers that day were also probably supercells with all the ingredients in place. 

Plenty of other posts from that day there is one with the radar of Sleaford somewhere. 

Whilst setups like that are rare for uk you don’t always need a supercell to produce funnels / weaker tornadoes. This last year up here in Scotland had a confirmed funnel and one of the Scottish members posted pics can’t remember the date though also those radar screen grabs I posted yesterday usually when u see something like that it is a sign of possible rotation 

[Paul Sherman]

When In the USA I dont really overcook things as I find if you look at too many variables you can actually do more harm when picking a target. These are the things I will always look at which we can actually find on our Uk Storms in the next 5 months upto the end of September.

First thing I look at is obviously shear and I am looking for at least 30-35knts of Deep Layer Shear. Ideally you want your 2m winds out of the east of South East, your 850mb winds out of the south and at least 25knts of speed on those. Your 500mb winds out of the South West or West and again around 40knts so storms are not moving at warp speeds. Once you look at your Hodograph that should yield winds turning with height (Shear) and then look at your T'Td Spreads. In the Uk a few years back we had those Supercells in the Midlands with temps of 75 and Dewpoints of 66. That is an amazing Spread even in the USA that would make you sit up and take notice. Notice I have not even mentioned Cape yet ? It is not the be all and end all of Supercell formation and I have seen Tornadoes with as little as 500jkg of Cape. One thing the USA has that is quite rare in the Uk is the LLJ (low Level Jet) and this really helps to get storms spinning and gives that extra spin to Mesocyclones in the early evening, although rare in the Uk we have seen the LLJ nosing up from France before.

When we get a decent Set-Up in the Uk in the next few months it will be good for us to all look at the charts to see if any or all of these ingredients come into play.

[convector]

i think people overestimate what it takes to form a supercell in this country...

[Eagle Eye]

[Paul Sherman]

Yep @ Kirkcaldy 

Those 28th June Storms were the ones I was thinking about, Baseball sized hail in Leicester and a Classic Supercell with Tornado in Sleaford.

The conditions were absolutely superb on that day, everything pointed to Supercell Storms, 40knts of Deep Layer Shear and low LCL's.

Lets hope for more of those this year 

[Thunder and Lightning]

6 minutes ago, Paul Sherman said:

When In the USA I dont really overcook things as I find if you look at too many variables you can actually do more harm when picking a target. These are the things I will always look at which we can actually find on our Uk Storms in the next 5 months upto the end of September.

First thing I look at is obviously shear and I am looking for at least 30-35knts of Deep Layer Shear. Ideally you want your 2m winds out of the east of South East, your 850mb winds out of the south and at least 25knts of speed on those. Your 500mb winds out of the South West or West and again around 40knts so storms are not moving at warp speeds. Once you look at your Hodograph that should yield winds turning with height (Shear) and then look at your T'Td Spreads. In the Uk a few years back we had those Supercells in the Midlands with temps of 75 and Dewpoints of 66. That is an amazing Spread even in the USA that would make you sit up and take notice. Notice I have not even mentioned Cape yet ? It is not the be all and end all of Supercell formation and I have seen Tornadoes with as little as 500jkg of Cape. One thing the USA has that is quite rare in the Uk is the LLJ (low Level Jet) and this really helps to get storms spinning and gives that extra spin to Mesocyclones in the early evening, although rare in the Uk we have seen the LLJ nosing up from France before.

When we get a decent Set-Up in the Uk in the next few months it will be good for us to all look at the charts to see if any or all of these ingredients come into play.

On a different note of supercell development, in the UK I think it is a lot easier to get a discrete mode than the US, as lots of the times when the ingredients are there in the summer it is much rarer for a deep low pressure to develop with strong fronts, and with less forcing the mode doesn't grow upscale to a massive line. Especially in the US when the main moisture source is moisture return being dragged up from the GoM which tends to require a deepening low pressure to do easily, so the the fronts tend to have stronger forcing.

[Kirkcaldy Weather]

Some more on that day here 

28th June 2012

STRATUSDECK.CO.UK

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For many people in the UK, including meteorologists and weather enthusiasts, June 28th 2012 was a day to remember. In the afternoon, violent supercell thunderstorms...

 

Error - Cookies Turned Off

RMETS.ONLINELIBRARY.WILEY.COM

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Dept of Meteorology - University of Reading

WWW.MET.READING.AC.UK

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Home page for the Department of Meteorology at the University of Reading

And the sleaford tornado 

 

[Windblade]

Black here now, a cell is coming from the northwest with visible vigra.

 

Edited May 1, 2020 by Windblade

[Zak M]

Just found some more videos of that 28th June 2012 storm, good god!!

 

 

 

 

[Thunder and Lightning]

1 minute ago, Kirkcaldy Weather said:

Some more on that day here 

28th June 2012

STRATUSDECK.CO.UK

---

For many people in the UK, including meteorologists and weather enthusiasts, June 28th 2012 was a day to remember. In the afternoon, violent supercell thunderstorms...

 

Error - Cookies Turned Off

RMETS.ONLINELIBRARY.WILEY.COM

---

 

Dept of Meteorology - University of Reading

WWW.MET.READING.AC.UK

---

Home page for the Department of Meteorology at the University of Reading

And the sleaford tornado 

 

Thanks for the video! I have never seen this one before and it is nice to see a tornado like that properly touch down and not just be from a cold front but an actual supercell! Looks like the sound has been turned off on purpose though...  (unless that's just my computer)

[Kirkcaldy Weather]

Wasn’t paying attention got some cells nearby not heard anything yet 

[Eagle Eye]

[Zak M]