Storms and Convective discussion - 10th April 2020 onwards

[Tim Bland]

1 hour ago, viking_smb said:

the lightning is associated with a trough, (if you care to look at the met office surface pressure charts) which is moving away from us

I disagree. If you look at the Met office charts you will see there is a cool front slipping south and a warm front edging north. The current strikes are associated with the warm front which is shown to be over us by tomorrow morning. Looking at the observed lightning you can also see it is coming north. 

[Flash bang flash bang etc]

I dunno, only just looked and while it’s lovely to see storms heading this way across the channel it’s literally the 10th time this has happened and they won’t make it here.

Forecast is for rain and a <5% chance of lightning. I trust the forecast.

[Eagle Eye]

It's warmer today than previous days.....

 

 

[Thunder and Lightning]

I'm looking at the GFS forecast soundings for next week and just hoping...

[Eagle Eye]

for Monday it's saying 80%.

[Flash bang flash bang etc]

12 minutes ago, Xanderp009 said:

for Monday it's saying 80%.

Monday next week?

You know I have a really weird feeling that that might change. Spooky, really.

[Eagle Eye]

the dark purple is where storms could form......... 

[StormLoser]

The rain radar is nice to look at. Heavy rain with embedded CN and lightning all heading north.

Yeah, right. Pull the other one...     

[ChannelThunder]

1 hour ago, Flash bang flash bang etc said:

I dunno, only just looked and while it’s lovely to see storms heading this way across the channel it’s literally the 10th time this has happened and they won’t make it here.

Forecast is for rain and a <5% chance of lightning. I trust the forecast.

Absolutely, you can see on the radar that it's already becoming standard frontal rainfall over there. If there had been a chance of storms over here, we would have been talking about it for days, and there would have been convective outlooks and the like issued. 

[Eagle Eye]

it looks like the Storm could miss most of the channels Water..... 

[Flash bang flash bang etc]

36 minutes ago, Xanderp009 said:

it looks like the Storm could miss most of the channels Water..... 

This doesn’t make any sense.

[Flash bang flash bang etc]

39 minutes ago, lancem said:

Absolutely, you can see on the radar that it's already becoming standard frontal rainfall over there. If there had been a chance of storms over here, we would have been talking about it for days, and there would have been convective outlooks and the like issued. 

Agreed. There are such things as surprise storms, but usually some of the tells are there that there’s a chance of something happening. Yes the clouds do actually have that pre-storm look to them, but this is because we are forecast convective rain - so that’s what will very likely happen. Every time there’s a southerly and France get storms it doesn’t automatically mean it will transfer.

Ppl need to calm down and go on youtube and watch some thunder videos.

(Thursday is our next chance imho)

[Mitch the motorbike storm]

Any chance for storms in south east tonight? Or am I asking for a miracle

[Zak M]

15 minutes ago, Mitch perrott said:

Any chance for storms in south east tonight? Or am I asking for a miracle

No chance! 

[Flash bang flash bang etc]

I’m doing a clap at 10pm tonight for two minutes - in honour of the storm forecast - because it was right

[James1979]

1 hour ago, Mitch perrott said:

Any chance for storms in south east tonight? Or am I asking for a miracle

South East France maybe! 

[Allseasons-Si]

Convective Weather

WWW.CONVECTIVEWEATHER.CO.UK

---

Forecasting thunderstorms and severe convective weather across the British Isles and Ireland for up to the next 5 days.

 

[Summer Sun]

Day 2 Convective Outlook

VALID 06:00 UTC Wed 29 Apr 2020 - 05:59 UTC Thu 30 Apr 2020

ISSUED 20:26 UTC Tue 28 Apr 2020

ISSUED BY: Dan

A broad LOW threat level has been issued to cater for the very low risk of isolated lightning strikes that may occur with various weather features during this 24 hour forecast period. However, for most places the risk is considered very low, and hence the vast majority of the large LOW threat area will remain void of any lightning.

At least two organised occlusions, and associated bands of rain, will sweep northwards and eastwards across the British Isles during this period, one during Wednesday daytime, and a second primarily during the evening and night. In both cases, these features will initially be quite active given strong forcing aloft, with heavy bursts of rain and embedded deep convection likely as they approach southern Ireland and southwest England, but as the forcing aloft shears away to the northwest, the bands of rain are expected to gradually weaken as they track farther northeast, eventually stalling somewhat over Scotland while decaying. In general, the risk of lightning will be greatest with these features as they approach southern Ireland/southwest Britain (20-25%), the risk then reducing as they push farther north and east (5-10%). CAM guidance suggests meso-vortices may develop along the rear edge, especially located near the most intense convection, and this may aid the potential for damaging gusts of wind (50-60mph possible over open waters and exposed Celtic Sea coasts). Multi-model guidance suggests Pembrokeshire and along the coast of Cardigan Bay could see some strong gusts of wind during Wednesday morning, for example.

In-between these two occlusions there will likely be a window of cloud clearance coinciding with peak diurnal heating, particularly in a swathe from central Ireland across Wales and central southern England. With the mid-levels having cooled considerably by this stage, this may yield a couple hundred J/kg CAPE - more especially over Ireland, with greater proximity to the upper cold pool. As a result, some convection and a few showers could develop, although the pronounced mid-level dry layer will act as a lid, restricting the depth of convection and hence limiting the overall lightning risk. Nonetheless, a 10-15% risk of lightning may exist over Ireland during the afternoon hours, although the second occlusion will already be arriving in southern Ireland by mid/late afternoon.

Behind the second occlusion, a pronounced shortwave will approach the Celtic Sea and SW England on Wednesday night, driving deep convection and numerous showers which may evolve into a comma-type feature by the end of the night. Given some reasonable speed and directional shear, strong forcing aloft and 300-500 J/kg CAPE, some sporadic lightning seems possible. A low-end SLGT (30%) has been issued to cater for this risk. Once again, some damaging gusts of wind could occur near exposed coasts and some hail is also likely in the most intense cells. Ironically, this type of setup is more akin to autumn/winter rather than mid/late spring!

http://convectiveweather.co.uk/forecast.php?date=2020-04-29

[Thunder and Lightning]

Loving the look of this radar image! Any chance of it being a supercell?

[Eagle Eye]

[ChannelThunder]

Still a way off, but the potential plume event next week is beginning to take a really nice shape on GFS, which hits us with two rounds of activity on both Tuesday and Wednesday nights. Sadly, ECM is really not interested and keeps it firmly as a cut-off low near Portugal. A lot to play for. 

Edited April 29, 2020 by lancem

[Eagle Eye]

today i think this storm won't produce as much but the later storm i'm going to keep an eye on.

[Allseasons-Si]

 

[Eagle Eye]

Seeing a lot of upward growth here.

[Eagle Eye]