Storms and Convective discussion - June 2023

[Rufus Butterfield]

Just now, alexisj9 said:

It less capped in the west.

Ok that makes sense

[SteveB]

Fully expect to see nothing here again. 

Would be nice to get a bit of rain. 

[Metwatch]

Instability is coming, slowly but surely.

[Eagle Eye]

Well first look at tomorrow as today is less interesting than tomorrow. I think without the capping, it would be a guaranteed moderate and potential high risk.

There are significant levels of low-level energy from a very bouyant surface layer unaffected by downwards mixing of colder dewpoints (benefits of an initially unopen sector). If it weren't for basically 0 shearing, these could potentially be severe thunderstorms beyond the rainfall. However, these look to take up a decent amount of the moisture within the air and could cause significant rainfall for surface flooding in areas due to their slow moving nature. Large 3CAPE values appear likely which is a good sign for active and significant thunderstorms. The CIN and borderline convective temperature in places is keeping these fairly isolated but clustering in places of weak CIN and so some areas especially in south Wales and up to parts of NW England may see these clusters of high activity. 

There is a lot of moisture available from the significant plume of PBL Theta-E air and I suspect more moisture at the surface. The saturation is not too high and I suspect a pot of models are overdoing the time it takes for the cloud to clear and we'll see convective initiation earlier than expected. If that happens than slightly further east initiation and more eroding of capping is likely. The severeness won't be lowered too much and so surface flooding still looks to be a probably issue so I suspect that me and Jay will go for a moderate somewhere along with a severe risk. The gravity waves sent out by the occluded front may force storms a bit taller than the equilibrium level along with the very tall possible cloud heights. That in turn could lead to further gravity waves sent out and a secondary area of storms further east and also north than the main cluster of storms. So CAM'S could quote possibly be underdoing the eastern extent of convection even with the CIN in place. The cloud should last for longer but assuming there are gaps then the bouyancy and 3CAPE should build to similar levels further east and north than currently forecast so I wouldn't be surprised if we saw a very active storm probably to the northeast of the main line of isolated/clustered storms. So northern parts of central England could be in for a surprise depending on how many gaps in cloud cover there is and how much cloud cover there is in the first place actually.

There are significant low-level lapse-ratws and surface bouyancy so a lot of vigorous convection is likely to be released as some of the models are showing. However, the bouyancy beyond the PBL (planetary boundary layer) appears to be lowering fairly quickly so we'll be relying on CAPE and other forcing methods quite early in. We cannot assume shearing is good enough to allow maximum theoretical height bit its clear CAPE is going to be fairly strong.

PV lobe from decaying occluded in the SW and the south of Ireland and secondary PV plane in south Wales with a third one just south and west of Manchester suggesting best forced storms will be in those general regions but these still move throughout the day. Storms form without PV lobes and planes but with one its generally much easier to work out the forcing for them and also the mode. Generally, clustering in south Wales looks to be the main mode similar to west of Manchester but it depends on the capping there. 

With very tall EL's and decently low LCL's, the entrainment CAPE increases (the range between the two helps increase the entrainment CAPE) and the 3CAPE looks significant and this isn't even in the strongest area. That makes it a very good sounding for lightning along with the saturation not being too much though the LCL being fairly lifted is still a small worry, the EL is one of the tallest we've seen so far this year. I don't imagine reaching the convective temperature will be as much of a worry further west rather than in the east but if the temperatures are a couple degrees above expected in the east, I wouldn't be surprised if someone like me actually gets something.

E.G.

Just seen the AROME and it favours that gravity wave induced convection towards the SE rather than the NE. Something to keep an eye on for model trends and bear in mind they dont handle gravity waves well at all in the first place so it could be even more widespread.

Similarly, on Sunday there's large 3CAPE again with significant amounts of low-level instability but less confidence than Saturday just yet. May be a high risk day if confidence increases with less worry about cloud cover and therefore less worry about capping. Fairly widespread significant thunderstorms again look likely but we'll have to see whether the EL is as tall as tomorrow.

Low-level shear is actually quite good for something like a mini-Supercell but the deep-layer shear is not so good. Arguably a few knots better than Saturday but not by much. May slightly help increasing the clouds height.

Here's why SundAy could be so significant. Looking along the trough and there's near 2000 J/KG of MUCAPE likely with very deep EL's and LCL's close to the ground. I really wouldn't be surprised if me and Jay decided to go for a small high risk somewhere if the models get better confidence on one risk area. 3CAPE nearing 200 J/KG is again significant and more so than Saturday, I really feel like Sunday could be more active than Saturday and it's looking like it could be one of if not the biggest of the year for somewhere where an extremely active storm dumping a lot of rain and maybe small to near severe hail possible.

CAPE looks skinnier on Monday but still there for another decent day of thunderstorm activity. I suspect that's not the area of highest CAPE that day though and its clear that once again cloud heights could be quite tall so lightning frequency could be quite frequent again.

That's all for now.

Edited June 9, 2023 by Eagle Eye

[camturbo]

41 minutes ago, Eagle Eye said:

Well first look at tomorrow as today is less interesting than tomorrow. I think without the capping, it would be a guaranteed moderate and potential high risk.

There are significant levels of low-level energy from a very bouyant surface layer unaffected by downwards mixing of colder dewpoints (benefits of an initially unopen sector). If it weren't for basically 0 shearing, these could potentially be severe thunderstorms beyond the rainfall. However, these look to take up a decent amount of the moisture within the air and could cause significant rainfall for surface flooding in areas due to their slow moving nature. Large 3CAPE values appear likely which is a good sign for active and significant thunderstorms. The CIN and borderline convective temperature in places is keeping these fairly isolated but clustering in places of weak CIN and so some areas especially in south Wales and up to parts of NW England may see these clusters of high activity. 

There is a lot of moisture available from the significant plume of PBL Theta-E air and I suspect more moisture at the surface. The saturation is not too high and I suspect a pot of models are overdoing the time it takes for the cloud to clear and we'll see convective initiation earlier than expected. If that happens than slightly further east initiation and more eroding of capping is likely. The severeness won't be lowered too much and so surface flooding still looks to be a probably issue so I suspect that me and Jay will go for a moderate somewhere along with a severe risk. The gravity waves sent out by the occluded front may force storms a bit taller than the equilibrium level along with the very tall possible cloud heights. That in turn could lead to further gravity waves sent out and a secondary area of storms further east and also north than the main cluster of storms. So CAM'S could quote possibly be underdoing the eastern extent of convection even with the CIN in place. The cloud should last for longer but assuming there are gaps then the bouyancy and 3CAPE should build to similar levels further east and north than currently forecast so I wouldn't be surprised if we saw a very active storm probably to the northeast of the main line of isolated/clustered storms. So northern parts of central England could be in for a surprise depending on how many gaps in cloud cover there is and how much cloud cover there is in the first place actually.

There are significant low-level lapse-ratws and surface bouyancy so a lot of vigorous convection is likely to be released as some of the models are showing. However, the bouyancy beyond the PBL (planetary boundary layer) appears to be lowering fairly quickly so we'll be relying on CAPE and other forcing methods quite early in. We cannot assume shearing is good enough to allow maximum theoretical height bit its clear CAPE is going to be fairly strong.

PV lobe from decaying occluded in the SW and the south of Ireland and secondary PV plane in south Wales with a third one just south and west of Manchester suggesting best forced storms will be in those general regions but these still move throughout the day. Storms form without PV lobes and planes but with one its generally much easier to work out the forcing for them and also the mode. Generally, clustering in south Wales looks to be the main mode similar to west of Manchester but it depends on the capping there. 

With very tall EL's and decently low LCL's, the entrainment CAPE increases (the range between the two helps increase the entrainment CAPE) and the 3CAPE looks significant and this isn't even in the strongest area. That makes it a very good sounding for lightning along with the saturation not being too much though the LCL being fairly lifted is still a small worry, the EL is one of the tallest we've seen so far this year. I don't imagine reaching the convective temperature will be as much of a worry further west rather than in the east but if the temperatures are a couple degrees above expected in the east, I wouldn't be surprised if someone like me actually gets something.

E.G.

Just seen the AROME and it favours that gravity wave induced convection towards the SE rather than the NE. Something to keep an eye on for model trends and bear in mind they dont handle gravity waves well at all in the first place so it could be even more widespread.

Similarly, on Sunday there's large 3CAPE again with significant amounts of low-level instability but less confidence than Saturday just yet. May be a high risk day if confidence increases with less worry about cloud cover and therefore less worry about capping. Fairly widespread significant thunderstorms again look likely but we'll have to see whether the EL is as tall as tomorrow.

Low-level shear is actually quite good for something like a mini-Supercell but the deep-layer shear is not so good. Arguably a few knots better than Saturday but not by much. May slightly help increasing the clouds height.

Here's why SundAy could be so significant. Looking along the trough and there's near 2000 J/KG of MUCAPE likely with very deep EL's and LCL's close to the ground. I really wouldn't be surprised if me and Jay decided to go for a small high risk somewhere if the models get better confidence on one risk area. 3CAPE nearing 200 J/KG is again significant and more so than Saturday, I really feel like Sunday could be more active than Saturday and it's looking like it could be one of if not the biggest of the year for somewhere where an extremely active storm dumping a lot of rain and maybe small to near severe hail possible.

CAPE looks skinnier on Monday but still there for another decent day of thunderstorm activity. I suspect that's not the area of highest CAPE that day though and its clear that once again cloud heights could be quite tall so lightning frequency could be quite frequent again.

That's all for now.

Thanks eagle eye very informative,must of took you ages to write it down. Sounds like there is a possibility of some big storms for some if everything falls into place. I would be happy for some rain but a storm would be a bonus

[TallPaul]

Nice to see the Nantes storm factory in France has started it's shift... and is really beginning to pump out the action. Due North for several miles, then heading North West.

Tonight in the SW could be interesting...

[Sparkiee storm]

UKV 12z looks a little more active for Saturday and Sunday, potent storms around the welsh border and West Midlands tomorrow and in a line down towards the Chilterns. Sunday looks a little more widespread as others have been saying and storms could fire in Wales, Midlands, and parts of Ireland and Scotland too. But there looks to be a small cluster developing on Sunday afternoon/evening across the Midlands. It will change again but promising signs are still there that there will be some storms about. The charts reminds me a bit like 27/28th May 2018 and the week starting 13th June 2020 when there was also low pressure to the SW bring warm, humid air, the only difference this time is that it will be hotter. Also may be similar to 28th July 2008, when the temps reached 30c and scattered but potent thunderstorms broke out later in the afternoon and evening. All in all though starting to get a little more excited now.

 

[LIGHTNING ACTION]

Looking forward towards Saturday and Sunday!

[Flash bang flash bang etc]

Seems like the south and south east ain’t the best places to be for this series of potential events. And I’m not really ready to travel too far this weekend. Hoping for some slight changes to the near-term forecasts I’ve read so far - southward and eastward shifts are needed!

[kold weather]

7 minutes ago, Flash bang flash bang etc said:

Seems like the south and south east ain’t the best places to be for this series of potential events. And I’m not really ready to travel too far this weekend. Hoping for some slight changes to the near-term forecasts I’ve read so far - southward and eastward shifts are needed!

I wouldn't be too surprised if isolated cells pop off even down here. Should make for some great photos given they should be fairly discrete.

Main action probably just a little too far north/west for us lot though.

[Flash bang flash bang etc]

6 minutes ago, kold weather said:

I wouldn't be too surprised if isolated cells pop off even down here. Should make for some great photos given they should be fairly discrete.

Main action probably just a little too far north/west for us lot though.

Good question actually: are we expecting mainly clear skies away from any storms that do develop?

especially into the evening that would be amazing from a photographic point of view

[joggs]

Daft question I know but does anybody think I could miss storms in Monday evening here in West Yorkshire(Bingley)?. Got a out do on.

Tia

Edited June 9, 2023 by joggs

[Arnie Pie]

1 hour ago, Sparkiee storm said:

All in all though starting to get a little more excited now.

Yes getting that feeling myself, sadly no livestream from Birmingham

Unfortunately Brumcam v0.3 passed away in late April, after a short condensation illness.
A good innings thought, she was 112 (in digital years) when she passed 

My cameras will be ready however

[ChezWeather]

Certainly looking too far NE here, a short drive over the Peak District is on the menu though, chase mode activated

[Row w]

Evening peeps  looking set to be an interesting weekend of weather, couldn't ask for better my two favourite weather types, thunderstorms and heat 

[ChannelThunder]

11 minutes ago, Row w said:

Evening peeps  looking set to be an interesting weekend of weather, couldn't ask for better my two favourite weather types, thunderstorms and heat 

You're right in the corridor of most risk tomorrow! Good luck

[Guest]

Just on Poole beach, high cloud from the French storms coming across the channel and a line of Ac Cas bubbling up in front. 

[Mapantz]

I can't wait to get the cloudy weekend out of the way. Back to more sunshine next week.

[I remember Atlantic 252]

37 minutes ago, Row w said:

Evening peeps  looking set to be an interesting weekend of weather, couldn't ask for better my two favourite weather types, thunderstorms and heat 

Too far east here I feel, could be a day of storms out to my west, could even see lightning to my west eccy/NW, or Telford SW 

[minus10]

1 hour ago, Flash bang flash bang etc said:

Seems like the south and south east ain’t the best places to be for this series of potential events. And I’m not really ready to travel too far this weekend. Hoping for some slight changes to the near-term forecasts I’ve read so far - southward and eastward shifts are needed!

Yes.....dissappointing from.latest forecasts after the initial forecasts  particularly for Monday...( although we are still in met office warning areas here)...... we have the heat but not the exact amount of moisture apparently...this storm business is so intricate , sensitive and fickle...hope at least to see some cloud tops and really could do with some rain now given the weather will return to dry once this stormy for some period is over...

[Guest]

30 minutes ago, Mapantz said:

I can't wait to get the cloudy weekend out of the way. Back to more sunshine next week.

I don’t think it’ll be that bad to be honest. 
 

But one Arome or Arpege going to be very wrong tomorrow. 
 

Edited June 9, 2023 by Alderc

[viking_smb]

5 minutes ago, Alderc said:

I don’t think it’ll be that bad to be honest. 
 

But one Arome or Arpege going to be very wrong tomorrow. 
 

top one, south wales in for direct hit, going to be interesting down barry docks as we got the sea cadet district power and rowing comp, and i'm on safety

[TallPaul]

5 hours ago, TallPaul said:

Nice to see the Nantes storm factory in France has started it's shift... and is really beginning to pump out the action. Due North for several miles, then heading North West.

Tonight in the SW could be interesting...

2 hours later... Well, second thoughts maybe?

The channel seems to be wanting to eradicate the French storms quicker than I can say "oh b*llocks"... 

I think I'll look a again (in desperation for a miracle) after midnight...

[Harry]

A few of the models suggesting my area could be in with a chance at times over the weekend - nothing widespread but certainly a chance. Let’s see 

[Rufus Butterfield]

UKV showing storms further east and more scattered on Sunday so some of us may get a surprise