Storm & Convective Discussion - 1 September 2015 onwards

[MP-R]

I think my thoughts of a rumble of thunder are confirmed this morning. That makes it the second 2nd March in a row with thunder. In fact it's been quite similar to 2nd March last year so far.

[Evening thunder]

A rumble reported here this morning, though I didn't hear it as I was out. Heavy hail and some snow in that band too, with very strong winds. A proper covering of hail in places such as Sidbury (actually from a heavy shower just before the main band), covering the main road about half an inch deep, but localised.

Nice to see the French getting a 'British import'.. why can't it often be the other way round?

 

[Raidan]

Another thunderstorm on Wednesday second off the year had to stop work again doing alright this year so far.

[William Grimsley]

Had a rumble of thunder in the heavy snow shower on 02/03/2016 here.

Edited March 8, 2016 by William Grimsley

[weather09]

Nice 'plume' on the 6z GFS for next weekend... 

Likely an elevated affair given fairly poor low-level moisture return early season, though w'erly mid-level jet winds and steep lapse rates would ensure multicell/possible elevated MCS mode. 

Would do well to see something like that so early in the year.

 

Edited March 10, 2016 by weather09

[East_England_Stormchaser91]

1 hour ago, weather09 said:

Nice 'plume' on the 6z GFS for next weekend... 

Likely an elevated affair given fairly poor low-level moisture return early season, though w'erly mid-level jet winds and steep lapse rates would ensure multicell/possible elevated MCS mode. 

Would do well to see something like that so early in the year.

 

Bring it on! Hope this year is as good as the last. Can't believe some of the storms that happened in July last year. Really were quite sublime in many areas. That one that occurred over the North giving that silent lightning display on the evening of the 1st was out of this world by any worldwide standards, let alone here! Not to mention what followed 3 days later. 

Roll on Spring and summer! 

[Stormyking]

Would be incredible if that pulled off on the 6z so early in the year! Agreeing with you 09, would be a Elevated on affair, also some decent Mid Level Cape and LI pushing up towards the South and South East too

 

 

[Spikecollie]

On 3/10/2016 at 1:35 PM, East_England_Stormchaser91 said:

Bring it on! Hope this year is as good as the last. Can't believe some of the storms that happened in July last year. Really were quite sublime in many areas. That one that occurred over the North giving that silent lightning display on the evening of the 1st was out of this world by any worldwide standards, let alone here! Not to mention what followed 3 days later. 

Roll on Spring and summer! 

Here in Limousin, France, we're progged 20c for next weekend. A nice plume is possible! We still have the dents in our car bonnet as a reminder of last July in Yorkshire. My picture of  the hail is still on the BBC website. Not sure I want that again, but it was memorable! Neither do I want a strike on my house like I had here in January, but some T&L is always nice.

[MP-R]

Perhaps the potential for an isolated thunderstorm somewhere on Sunday somewhere across the west? N-W has intermittently shown a greater than 50% chance of a storm for a few days, and Wunderground is persistent in its lightning symbol at least for my location. Fingers crossed! Would be a treat to get two thunder days into March.

[Speedway Slider]

When does a new thunderstorm season officially start? Or put it another way, what is the Netweather start and finish of the UK thunderstorm season? And then, what are classed as out of season thunderstorms?

[Mokidugway]

9 hours ago, Speedway Slider said:

When does a new thunderstorm season officially start? Or put it another way, what is the Netweather start and finish of the UK thunderstorm season? And then, what are classed as out of season thunderstorms?

Mid March to October for home grown storms due to insolatiion I would say .

[Harry]

I'd go with mid March to October too, although it's officially (for me) when I start revisiting here

Had my eye on Sunday for a few days now - looking good for some isolated rumbles quite widely! 

[Supacell]

A lot of weather going on in the next 72 hours with some very squally rain today and Storm Katie later in the Easter break, but I want to concentrate on tomorrow (Easter Day) specifically for the risk of convective activity and thunderstorms.

Following today's squally rain band a showery airflow takes over and through tomorrow lapse rates increase across the UK in response to limited surface heating from the now strengthening sun. CAPE is nothing overly special in the grand scheme of things but GFS forecasts 300-500J/kg, which for March is very respectable. WRF shows a little more but NMM somewhat less. However, all models agree on the risk of some thundery activity among numerous showers through tomorrow.

Using the GFS, showers already around southern and western coasts will become more widespread by late morning and through the afternoon, with the main risk transferring NE whilst dying away from the SW. The storm risk would therefore appear higher in northern and eastern areas as here will benefit from more surface heating through the morning. The chart for lapse rates shows where the highest lapse rates are at midday and by mid-afternoon.

       

CAPE charts for 12z and 15z tomorrow show the same story with instability dying from the SW through the day whilst increasing further north and east

      

Deep Layer Shear looks to increase from the south but is too late to affect the areas where heavy showers and thunderstorms develop and so showers that do develop will most likely be of the pulse type variety. Having said that, showers could form into bands along troughs and this would likely aid organisation. There also looks to be some 15-20 knots of low level shear which brings about a slight risk of something more potent and a slight tornado risk, especially around the east coasts of Lincolnshire and around the Humber. Chart below from www.lightningwizard.com/maps.

In contrast, the high resolution Euro4 shows the Humber and Lincolnshire seeing very few showers with areas across Central and Western areas more at risk. The Euro4 shows a line running from the Bristol Channel to the Wash being one of a few SW to NE running zones, another being from Mid-Wales to Yorkshire. It is probably too early to advise yet on where would likely have the chance of seeing a storm or two tomorrow, but I have reasonable confidence now on there being a storm risk.

Any stronger showers and thunderstorms tomorrow will have the potential to produce small hail (up to 1cm diameter) and gusty winds along with localised flooding. Lightning activity is likely but it will not be a widespread occurrence. Nevertheless it is the best set up of this year so far and for me looks to officially open the 2016 storm chase season

Showers quickly lose their intensity late in the day for all areas with risk moving out into the North Sea by the time the sun goes down (an hour later than it does tonight). By this time those of us in England and eastern Wales will be looking south for the arrival of Storm Katie. She could provide some very heavy rainfall and severe gales overnight into Monday, especially for southern and eastern parts.
 

[Stuart]

Ok not posted for a long time here go

 

Day 2 Convective Outlook

VALID 06:00 UTC Sun 27 Mar 2016 - 05:59 UTC Mon 28 Mar 2016

ISSUED 08:56 UTC Sat 26 Mar 2016

ISSUED BY: Dan

Upper trough swings NEwards across British Isles through Sunday, with cold air aloft steepening lapse rates in response to diurnal heating. Scattered showers and a few weakly-electrified thunderstorms will develop, sometimes becoming organised into bands, with the greatest chance/coverage of lightning expected in the two SLGT areas - moreso in the eastern zone from S Yorks down to Lincs. Even so, only a low-end SLGT has been issued, but for many it will be the first proper convective day of the year.

 

Small hail is likely to accompany some of the showers, and given some LLS, particularly in the eastern SLGT, there is scope for perhaps a funnel or weak tornado.

 

http://www.convectiveweather.co.uk/forecast.php?date=2016-03-27

 

 

[matty40s]

Definite squall line forming now from Brittany France in the South to lake dustrict in the North

[Paul]

Yep, looking pretty good on radar

[Mapantz]

Not too far away from here.. It usually breaks up over my area, and then regroups after it has passed through.    

[Chris.R]

 Was quite dramatic here, torrential rain and very strong gusts. 

  More fun tomorrow. Here we go again for another year! 

[Mapantz]

22 minutes ago, Chris.R said:

 Was quite dramatic here, torrential rain and very strong gusts. 

  More fun tomorrow. Here we go again for another year! 

Just arrived here.. a decent bit of rainfall.

Spoke too soon.. a bit pathetic here as usual. 

Edited March 26, 2016 by Mapantz

[Supacell]

Squall line just passed through here with some heavy rain and strong winds. The winds were roaring as it moved over. However nothing overly impressive.... until it moved about 5 miles east of here and then looks to have intensified quite markedly 

Oh well, chance of a rumble or two tomorrow to get excited about.

[William Grimsley]

6 hours ago, Supacell said:

A lot of weather going on in the next 72 hours with some very squally rain today and Storm Katie later in the Easter break, but I want to concentrate on tomorrow (Easter Day) specifically for the risk of convective activity and thunderstorms.

Following today's squally rain band a showery airflow takes over and through tomorrow lapse rates increase across the UK in response to limited surface heating from the now strengthening sun. CAPE is nothing overly special in the grand scheme of things but GFS forecasts 300-500J/kg, which for March is very respectable. WRF shows a little more but NMM somewhat less. However, all models agree on the risk of some thundery activity among numerous showers through tomorrow.

Using the GFS, showers already around southern and western coasts will become more widespread by late morning and through the afternoon, with the main risk transferring NE whilst dying away from the SW. The storm risk would therefore appear higher in northern and eastern areas as here will benefit from more surface heating through the morning. The chart for lapse rates shows where the highest lapse rates are at midday and by mid-afternoon.

       

CAPE charts for 12z and 15z tomorrow show the same story with instability dying from the SW through the day whilst increasing further north and east

      

Deep Layer Shear looks to increase from the south but is too late to affect the areas where heavy showers and thunderstorms develop and so showers that do develop will most likely be of the pulse type variety. Having said that, showers could form into bands along troughs and this would likely aid organisation. There also looks to be some 15-20 knots of low level shear which brings about a slight risk of something more potent and a slight tornado risk, especially around the east coasts of Lincolnshire and around the Humber. Chart below from www.lightningwizard.com/maps.

In contrast, the high resolution Euro4 shows the Humber and Lincolnshire seeing very few showers with areas across Central and Western areas more at risk. The Euro4 shows a line running from the Bristol Channel to the Wash being one of a few SW to NE running zones, another being from Mid-Wales to Yorkshire. It is probably too early to advise yet on where would likely have the chance of seeing a storm or two tomorrow, but I have reasonable confidence now on there being a storm risk.

Any stronger showers and thunderstorms tomorrow will have the potential to produce small hail (up to 1cm diameter) and gusty winds along with localised flooding. Lightning activity is likely but it will not be a widespread occurrence. Nevertheless it is the best set up of this year so far and for me looks to officially open the 2016 storm chase season

Showers quickly lose their intensity late in the day for all areas with risk moving out into the North Sea by the time the sun goes down (an hour later than it does tonight). By this time those of us in England and eastern Wales will be looking south for the arrival of Storm Katie. She could provide some very heavy rainfall and severe gales overnight into Monday, especially for southern and eastern parts.
 

Brilliant post, Supacell! So convective activity starts to go mad shortly after the clocks change. This may be a good sign for the Summer... Hehehehe!

[East_England_Stormchaser91]

Been a while, but 2016 is ready to kick off  starting from tomorrow morning, it isn't looking too bad! 

[Gonzolio Martinez]

It looks like it's getting more organised as it moves east. Wonder how long until it hits me.

[paul_montague]

Hey now I moved down South from Leeds I might get a decent storm..

[Spikecollie]

Storms, that are impressive for March, popping off in NW France now. They're supposed to happen down here in Limousin too later on, but we'll see what happens.