Storms and Convective discussion - November 2023 onwards

[viking_smb]

interesting

[Eagle Eye]

It's nearly that time of year (I mean 2-3 months is nearly right?) for the storms to come back properly. Hoping for a good year of course. 

[Thunders]

  i feel april is when we will start to see some of the one of first events of the season. it could be earlier if we get some warmth from france pushing up a few storms. i guess that the west will be the first to start the storm season followed by the rest of the country later on. hopefully this year is better than last year for the south and south east, and a few stormy days for those up north.

[Eagle Eye]

Convective Outlook️ 

Behind a cold front clearing east, there's some fairly strong buoyancy for the time of year that could form, allowing for some convective forcing in pockets mainly isolated to the SE but perhaps in some areas further north.

 

Good lapse-rates and 100+ J/KG of 3CAPE possible could well allow for sparodic lightning in showers forming behind the front in the SE. However, this would most likely rely on a storm taking full advantage of its surroundings by taking advantage of all the convective energy possible and so the deep-layet shear being low really limits the risk to sparodic lightning and mostly showery activity in the SE.

With the highly saturated layer just above the LCL and low LCL, it's not looking like showers would be highly photographable either.

 

Though, the weakening saturation post 850's do still favour lightning slightly so it's dependant on how much DLS can truly form, some models such as the ICON-D2 up to around 30 knots between 0-4 miles and that may be more favourable for lightning but given time of year and weak MLCAPE, still sparodic at best.

 

DCAPE, not bad low-layer shear and low LCL's might be enough for some fairly gusty conditions below any showers that do form as well but not enough to be severe worthy. Similarly, a low freezing height and some energy may be favourable for small hail but non-severe most likely. There may be a funnel or two from the low LCL's but apart from that no real support that I can see for a t ornado.

[Thunderspotter]

Hey if anyone's still up - my first message of 2024 (i think?)

 

Just had my birthday a few days ago and great to see that the chances for thunderstorms are starting to increase again.

I hope something happens tonight, I'll be up for an extra hour or so as our power's gone out for the second time running today. Fun times lol

Here's to a storm-filled action packed 2024!

[Eagle Eye]

 Thunderspotter Don't think they'll be anything of note tonight to be honest. Happy birthday for a few days ago.

[Thunderspotter]

 Eagle Eye haha fair enough. Risks are below the floor anyway. Thank you

[ChannelThunder]

 Eagle Eye absolutely no surprises there. I've always said Lincolnshire is the UK thunderstorm hotspot (usually followed by someone who lives there claiming they get nothing)

[Daniel_c150311]

personally I think there could be a few weak thunderstorms today, judging by the radars there seems to be some convection about but here are the areas I think there could possibly produce thunderstorms today/ areas with the most convection.

[Thunders]

view to Brighton. 
 

 view of the south towards Hastings 

Edited February 18 by Thunders

[CoventryWeather]

Nice to see some early season convection around. Couple of heavy showers towards Shropshire heading towards me, out and about to try and catch some of the cloudscapes. Doubt there's going to be any storms as it's rather early in the season and the sun isn't too strong, but nice to see anyways. 

[Metwatch]

Well that was nice to see. Spotted some convective cloud streets around (straight line of cumulus pretty much)

 

Then one of them started to produce a shower and ended up in a perfect spot to give a lovely rainbow despite it being quite light just north of here! 

Edited February 18 by Metwatch

[Metwatch]

Anvil from the stuff around Reading, webcam view vs drone:

 

Also a nice capture further southeast

Edited February 18 by Metwatch

[WeatherArc]

Couldn't ask for a better day, blue skies with some lovely cumulus around here and a few attempted towers.

Sbcape values in central and south eastern england around 200+j/kg with a few spots reaching 400 j/kg likely aided by steep lapse rates. 

Profile from around Coventry, note the steep lapse rates in all levels, MlCIN likely hindering any thunderstorm development though. 

[CoventryWeather]

Captured the same thing as @Metwatchearlier from Radford area. 

Been a stunning day, feeling warm. Convection was again lovely to see. 

Edited February 18 by CoventryWeather

[Metwatch]

Crep rays behind some convection, and some stunning golden hour scenes in general this evening. Much better than yesterday that's for sure!

[Daniel_c150311]

I’ve got some nice fluffy cumulus forming now.

[Thunders]

[LightningLover]

A very potent looking squall line on the outer reaches of the 15z UKV run today.

[Eagle Eye]

Lovely day for some convection.

 

 

 

 

[Ryan H]

 Metwatch
I saw a double rainbow during the drive back from Worthing.
 

Edited February 18 by Ryan H

[alexisj9]

Think I heard a distant rumble yesterday, on my way home, a shower missed to my west, the one that went over me before that was just rain.

[Thunders]

 LightningLover hopefully this actually happens. If it’s that far out tho, anything could happen 

[*Stormforce~beka*]

[Eagle Eye]

Convective Outlook️ 

Behind a clearing cold front, some heavy showers and storms could form around western Ireland and into Scotland where they may become more of a rash of showers. Some sporadic lightning is possible within these showers especially around western Scotland.

This is due to a trough just to the north of Scotland and one west of Ireland. Moist air is pulled up through Scotland, leading to a fairly strong amount of moisture convergence in western Scotland. A fairly buoyant airflow for the time of year is wrapped up and carried north by the trough and some of it hangs low into western Scotland with the moisture convergence.

This also coincides with very strong lapse-rates in similar areas and moderate saturation. Relatively high deep-layer shear also favours good situations for longer lived single-cell storms and a higher risk of lightning due to that and the moderate saturation.

All of the buoyant and moist airflow leads to 100+ J/KG of 3CAPE and 200-300 J/KG of MLCAPE so most convective potential is kept rather low in the atmosphere but the favourable buoyancy and shearing may act as kinematic forcings to push the storms beyond the 5.5-6km maximum mostly predicted. This depends on how much time the cells can live though and whether it will be more of a cycling mode especially with how messy some forecasts predict the showers to be organised.

The high shear and high 3CAPE may be favourable for a Supercell somewhere especially if it were later in the year but I don't think it'll be enough. Something to keep an eye out for and if one were to form then there's enough support for some slightly below severe hail. Similarly there's enough low-level shear and 3CAPE that if enough streamwise flow can be reached along the high potentially available vortcitiy fields mainly in western Scotland then a tornado couldn't be ruled out.

The western Ireland and surrounding area of western Scotland risk is more due to the general conditions surrounding the western Scotland risk than anything, in Ireland and isolated showers are a risk and the rash of showers may live long enough to push further east into Scotland whilst maintaining some lightning potential.

If the rash of showers does upscale as a proper PV lobe forms then the low-level energy and low-level sheer may allow for some relatively strong wind gusts as well. Nothing severe appears likely but an upscaling would increase the potential for that risk.