Convective/Storm Discussion Thread - 1st August onwards

[Eye to the sky]

8 minutes ago, Supacell said:

A storm just clipped me here in Belper. A few flashes and bangs but most went to my east. Still a nice opening to the 2018 season and more possibilities tomorrow.

Same here Supacell,stuck in traffic in Derby so was able watch the storm.A nice bolt of Forked Lightning and some decent pea sized hail too.Got back to Denby and we've no power.A good start to the season!.

[Dangerous55019]

Some impressively convective looking skies in the distance today, and I’ve just had a quick look at the lightning radar to see if anything has kicked off, and amazingly it has! 

Sadly nothing over me as yet... But the storm season is still young.

Good look to everyone who’s enjoying storms this evening. 

[Windblade]

Looks like convective weather were bang on with that forecast. Any chance the SE could get in on the action? There was talk of imports from France but the wind is blowing from the wrong way currently (sw instead of se). There was also mention of some home grown convection tonight moving in from the sw but I'm not so confident just yet as the convergence zone is definitely squarely in the midlands right now and any convection from the sw tends to fizzle out long before it gets here. 

Talk of possible storms again tomorrow but I think these will be daytime based. Will keep an eye out although I do love a good night time storm so hope I get to enjoy a few this season. Still, I'd still be extremely happy to see a good storm, day or night, preferably when I'm not working so I can take the time to really savour the moment. 

Edited April 3, 2018 by Windblade

[Dangerous55019]

It currently looks like most of the activity is now off the coast of Whitby.

[Supacell]

1 hour ago, Eye to the sky said:

Same here Supacell,stuck in traffic in Derby so was able watch the storm.A nice bolt of Forked Lightning and some decent pea sized hail too.Got back to Denby and we've no power.A good start to the season!.

I wish it could have been a little further west, but hey ho it is the closest I have come to a storm at home since 2015 so not complaining. My friend who lives in Ripley lost power too and he also reported hail.

More chances tomorrow, in fact a lot of the forecasters seemed more keen on tomorrow than today so fingers crossed. To my eye it looks like the best parameters are earlier on tomorrow, so maybe around the middle of the day. Usual suspects of Lincolnshire into East Yorkshire best placed but I will await the expert analysis.

 

[Gray-Wolf]

Well that is my first storm of the year! Passed to our west and over the moors but was a busy little thing with loud thunder.

[toggerob]

Nothing convective-wise here however it was ominously dark towards the east in confirmation with the NWRadar as the cell was passing around Nottingham. Tomorrow is looking promising for more of the same with a larger swathe of the midlands-north seeing some heavy showers in the afternoon.

[Weather-history]

 

[Summer Sun]

Day 2 Convective Outlook

VALID 06:00 UTC Wed 04 Apr 2018 - 05:59 UTC Thu 05 Apr 2018

ISSUED 20:43 UTC Tue 03 Apr 2018

ISSUED BY: Dan

Broad upper trough will clear eastwards across the British Isles on Wednesday, with a weakening upper-low lifting northeastwards during the morning and first half of the afternoon. Cold pool aloft will result in reasonably steep mid-level lapse rates over much of England and Wales, with diurnal heating helping to generate 300-600 J/kg CAPE. A surface low will drift northeast from Cornwall at 06z to The Humber by 18z - it is primarily on the northern and western flank where the best conditions for deep convection are expected. On the forward-side, most model guidance indicates more in the way of dynamic precipitation at times, and hence questionable as to how much lightning will occur here.

Provided there is sufficient insolation to lift surface temperatures to 10-12C with dewpoints of 8-9C, increasing low-level wind convergence will aid the developing scattered heavy showers and a few thunderstorms from early afternoon over northern England, the Welsh border and West Country, these then drifting eastwards through the afternoon hours - though very slow-moving in Yorkshire where the greatest concerns for some localised surface water flooding exist.

 

Hail up to 1.0cm in diameter is possible with the strongest cores, while a few funnel clouds or perhaps even a weak tornado will also be possible - moreso over The Pennines into Yorkshire where low-level convergence becomes maximised during the afternoon. Biggest limiting factor is likely to be excessive cloud cover which could serve to lower surface temperatures and inhibit deep convection. Both shear and mid-level lapse rates are weaker than on Tuesday, and so rather messy pulse-type convection is more likely. In any case, cooling of the boundary layer and ridging aloft will tend to cause a decay of showers during the late afternoon / evening hours.

 

http://www.convectiveweather.co.uk/forecast.php?date=2018-04-04

[Mokidugway]

Wouldn't rule out some quite interesting clouds tomorrow ,  level 1  in France mainly for hail but it's welcome back storm season 

[Flash bang flash bang etc]

I want storm

 

:-/

Edited April 3, 2018 by Flash bang flash bang etc

[Nick F]

Should be a more widespread risk of showers with hail and thunder today, more in my convective / storm forecast below:

Storm & Convective Forecast

Issued 2018-04-04 08:37:54
Valid: 04/04/2018 6am to 05/04/2018 6am

CONVECTIVE / STORM FORECAST - DAY 1 (WEDS 4TH APRIL)

Synopsis

A shortwave upper trough embedded in broadscale upper trough overspreading N Atlantic will move NE across the UK on Wednesday. A surface low and associated wrap around fronts will also move NE across England and Wales today, low clearing out into the North Sea by 00z. Thundery showers will circulate around the low over England and Wales, slow-moving fronts over Scotland will bring cloud, rain and hill snow.

... ENGLAND & WALES ...

Showers are already ongoing across SW England, Wales and West Midlands, as Increasingly cold air aloft spreading NE with upper trough steepens lapse rates from the SW, as these steepening lapse rates combine with surface heating in the strong April sunshine it allow cumulonimbus to build across many parts of England and Wales as duirnal warmth increases, convective clouds will gain sufficient height to allow glaciation to allow hail and also lightning in stronger cells. Showers will be slow-moving across central and western areas in vicinity of surface low (slack winds) moving NE - so this will bring an increased risk of localised flooding - exacerbated by recent large rainfall totals saturating the ground.

Issued by: Nick Finnis

https://www.netweather.tv/weather-forecasts/uk/convective

Edited April 4, 2018 by Nick F

[Supacell]

Still cloudy here with light rain. The cloud needs to break to allow anything thundery to develop. Hopefully cloud cover doesn't scupper it for today.

[Gordon Webb]

14 hours ago, Summer Sun said:

Day 2 Convective Outlook

VALID 06:00 UTC Wed 04 Apr 2018 - 05:59 UTC Thu 05 Apr 2018

ISSUED 20:43 UTC Tue 03 Apr 2018

ISSUED BY: Dan

Broad upper trough will clear eastwards across the British Isles on Wednesday, with a weakening upper-low lifting northeastwards during the morning and first half of the afternoon. Cold pool aloft will result in reasonably steep mid-level lapse rates over much of England and Wales, with diurnal heating helping to generate 300-600 J/kg CAPE. A surface low will drift northeast from Cornwall at 06z to The Humber by 18z - it is primarily on the northern and western flank where the best conditions for deep convection are expected. On the forward-side, most model guidance indicates more in the way of dynamic precipitation at times, and hence questionable as to how much lightning will occur here.

Provided there is sufficient insolation to lift surface temperatures to 10-12C with dewpoints of 8-9C, increasing low-level wind convergence will aid the developing scattered heavy showers and a few thunderstorms from early afternoon over northern England, the Welsh border and West Country, these then drifting eastwards through the afternoon hours - though very slow-moving in Yorkshire where the greatest concerns for some localised surface water flooding exist.

 

Hail up to 1.0cm in diameter is possible with the strongest cores, while a few funnel clouds or perhaps even a weak tornado will also be possible - moreso over The Pennines into Yorkshire where low-level convergence becomes maximised during the afternoon. Biggest limiting factor is likely to be excessive cloud cover which could serve to lower surface temperatures and inhibit deep convection. Both shear and mid-level lapse rates are weaker than on Tuesday, and so rather messy pulse-type convection is more likely. In any case, cooling of the boundary layer and ridging aloft will tend to cause a decay of showers during the late afternoon / evening hours.

 

http://www.convectiveweather.co.uk/forecast.php?date=2018-04-04

Biggest limiting factor is likely to be excessive cloud cover which could serve to lower surface temperatures and inhibit deep convection

your concerns may be a little justified

[Chris.R]

Still quite cloudy here but it’s 11.5°C so in that 10-12°C range mentioned. 

[toggerob]

A few breaks in the cloud appearing here, in-between is the convective clouds beginning to rise up.

[Dangerous55019]

Afternoon all 

As @SNOW_JOKE has said, there are now a few breaks in the cloud, and some rather nice convection going on out here at the moment. 

... Just had a small hail shower as well!

[Chris.R]

 Heavy shower here now. 

[Chris.R]

 Very heavy rain 15 minutes now. Seems to be developing overhead and getting heavier. 

[karyo]

Some heavy showers in west Manchester about half an hour ago but dry in the eastern half. 

[Chris.R]

 Absolutely torrential now and proper convective drops. This could electrify atany moment. 

[Dangerous55019]

Heavens have just opened here! 

Very heavy rain! 

Sadly I don’t think it’s gonna go bang for me today, but I reckon somewhere north east of me will see something... At a guess, I’m gonna say Manchester area when it starts? 

[karyo]

Absolutely throwing it down now!

[The PIT]

Sheffield shield not bothering to power up. Plenty of showers around but nearly all of them are light.

[Weather-history]

47 minutes ago, Dangerous55019 said:

Heavens have just opened here! 

Very heavy rain! 

Sadly I don’t think it’s gonna go bang for me today, but I reckon somewhere north east of me will see something... At a guess, I’m gonna say Manchester area when it starts? 

I am not sure it is going to go bang anywhere. Still no sferics anywhere.