Storms and Convective discussion - 1st August 2022 onwards

[Gordon Webb]

Day 1 Convective Outlook

VALID 06:00 UTC Mon 05 Sep 2022 - 05:59 UTC Tue 06 Sep 2022

ISSUED 07:07 UTC Mon 05 Sep 2022

ISSUED BY: Dan

Upper low will remain anchored to the west of Munster on Monday, with several shortwaves rotating around the main parent upper low. The first shortwave will drive an area of occasionally heavy rain across Scotland during the morning hours, but this should weaken and slowly clear northwards. The associated waving cold front will have largely cleared to the North Sea, but bends back westwards as a rather diffuse warm front lifting north across East Anglia and the Midlands at 12z, reaching Scotland by the evening. Surface heating of a moist low-level airmass (15-18C dewpoints) may yield several hundred J/kg CAPE by the afternoon hours across portions of England and Wales. In the absence of any large-scale forcing, most CAM guidance is rather unenthusiastic in developing many showers/thunderstorms; however coarser-resolution parameterised global model guidance continues to suggest the potential for a few scattered showers/thunderstorms developing in response to diurnal heating (and perhaps also aided by sea breeze convergence). Examination of forecast profiles suggests some hints of capping, with CAPE also fairly tall and skinny. Therefore it is hard to ascertain if many showers/thunderstorms will develop during the afternoon, but given unstable profiles and modest speed shear it is possible isolated/well-scattered activity could occur generally south of Merseyside-Humber initially, but expanding north of this line during the evening.

During the late afternoon/early evening, the next shortwave will arrive from the south and may be accompanied by a small surface low approaching from northern France. This seems tied to a quasi-warm front as advection of 16-18 850hPa Theta-W plume occurs into southern England. Surface heating coupled with cooling aloft as the shortwave approaches may yield CAPE in excess of 1,000 J/kg CAPE across parts of SW / Cen S England, Wales and the SW Midlands. CAM guidance varies, but there is a signal for multiple lines and/or clusters of very active thunderstorms to develop over these areas during the second half of the afternoon and through the evening hours as low-level convergence increases. Given increasing wind shear during the evening (30-40kts with low-level winds becoming more backed) some of these cells could become very lively and organised, with a supercell possible if cells can remain semi-discrete. This brings the threat of large hail, locally greater than 2.0cm in diameter, gusty winds and perhaps an isolated tornado - a SVR has been included to highlight these threats (main focus Dorset, Somerset, Wiltshire, Gloucestershire and SE Wales) alongside local surface water flooding, and also across portions of Ireland for gusty winds and an isolated tornado, primarily the afternoon and early evening hours here.

 

Thunderstorms will continue to migrate northeastwards across the Midlands and southern England through the evening and night hours, perhaps joined by additional cells approaching from the English Channel and NE France, and perhaps also expanding into more of N/NW England for a time. Later in the night there may be an uptick in elevated convection spreading into E/SE Scotland from the North Sea.

 

Edited September 5, 2022 by Gordon Webb

[biddie]

1 hour ago, Harry said:

Spider! Not as big as I feared when I turned the light on, but big enough

Ewww

[Coops241180]

50 minutes ago, Chris.R said:

Some large amounts of CAPE building at my location this evening on WRF questionn is will it be utilised.
Was also showing a big elevated cluster of storms passing overnight but on the latest run it’s completely gone.

where do you get the CAPE forecasts? is it a subscription thing?

[Ben Sainsbury]

Quite like yesterday I think we will likely see a few surprises! I'm gonna be heading out myself today, maybe around the Yeovil area?

[Dami]

So as i posted in the regionals, we had a something last night. Could hear our blind by the window banging the glass due to the wind, heard the rain then a long bang which sounded like a plane. So it was either a one hit wonder or i almost slept thru a storm last night.  Hubs only heard one crack and saw no lightning as the blind woke him.

gutted. 

[Atmogenic]

well from my experience from yesterday,

just before getting into be there was a few (about 15) flashes in the distance behind my house

the wind picked up and became more frequent which actually was helpful as my room was all hot

As I turned my light out about 20 mins later, 2 quick heavy showers came over our house

within i'd say 50mins or an hour later I had 3 rumbles of thunder in the distance

But after that I fell asleep and here we are now.

So all in all it was nothing, hope today is better which by the forecast, im more in the storm zone today

Edited September 5, 2022 by Atmogenic

[SteveB]

2 minutes ago, Ben Sainsbury said:

Quite like yesterday I think we will likely see a few surprises! I'm gonna be heading out myself today, maybe around the Yeovil area?

I wouldn't bother even venturing anywhere near Weston - I don't think we will see anything, continuing on with the same theme as it has been all year..... no storms!

 

Hardly got any rain last night, let alone storms! It's been poor.

[Guest]

both UKV, ARPEGE & AROME miles out with current activity, while not thundery lots of showers in the channel all three have almost nothing there for 9/10Z. ICON much closer to the mark. 

Arome has 1650j/kg of CAPE this afternoon, clearly blowing that up way over the top (arpege, not dissimilar) ICON just a few hundred joules of CAPE given all the messy showers and cloud. 

Edited September 5, 2022 by Alderc

[Chris.R]

33 minutes ago, Coops241180 said:

where do you get the CAPE forecasts? is it a subscription thing?

No I use the point forecasts from Meteociel. I like tables. You select the storm mode. You can either view the WRF GFS or Arpege. use the high altitude mode for steering winds, surface winds and lapse rates

here it is for Warrington

Meteociel - Prévisions météo fines WRF heure par heure techniques orage pour Warrington ( Grande-Bretagne )

WWW.METEOCIEL.FR

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Prévisions météo gratuites et précises à 3 jours heure par heure pour Warrington ( Grande-Bretagne ) basées sur le modèle WRF. Graphiques horaires de...

.

Edited September 5, 2022 by Chris.R

[Lynxus]

50 minutes ago, Coops241180 said:

where do you get the CAPE forecasts? is it a subscription thing?

GFS Weather Charts - updated four times daily - Netweather.tv

WWW.NETWEATHER.TV

Set the dropdown to "Cape + Lifted"

[A Face like Thunder]

Yellow thunderstorm warning now issued for Western parts of England and Wales, the East Midlands and London & the SE, covering the period from 14.00 today to 02.00 tomorrow.

Edited September 5, 2022 by A Face like Thunder

[TJS1998Tom]

Staying at Birmingham tonight. Looks like there could be good potential 

[BenFreeman_91]

My location is in the low risk zone but the met office have other ideas... 

[Coops241180]

26 minutes ago, Chris.R said:

No I use the point forecasts from Meteociel. I like tables. You select the storm mode. You can either view the WRF GFS or Arpege. use the high altitude mode for steering winds, surface winds and lapse rates

here it is for Warrington

Meteociel - Prévisions météo fines WRF heure par heure techniques orage pour Warrington ( Grande-Bretagne )

WWW.METEOCIEL.FR

---

Prévisions météo gratuites et précises à 3 jours heure par heure pour Warrington ( Grande-Bretagne ) basées sur le modèle WRF. Graphiques horaires de...

.

Cheers that's super useful...   i'm going to be at the kids football training at 6.... right when all that CAPE lands...  and all the forecasts i've looked at suggest that might be when things start kicking off today..   

[Flash bang flash bang etc]

So tonight I’m in Blackpool - with a big open view of the sky (and about 5 mins from the seafront) I’m seeing conflicting reports on potential, but hoping I can be in the right area again

What are the chances for the Blackpool area?

[Ben Sainsbury]

Storms W of Brest, sign of things to come later.

[Norfolk Sheep]

2 hours ago, Gonzolio Martinez said:

Well, all that completely missed me last night. Looked like I was in for a direct hit at one point before it all suddenly evaporated.

Charts 2 days ago were looking promising for here for Monday as well, and now there seems to be very little on the cards at all - it's all south of here. In fact, Norwich is *just* outside the SLGT zone for the third day in a row - it actually curves to avoid Norwich today

Been a very disappointing summer so far for storms. Had one or 2 very small storms very early on, at the end of spring. That's usually a bad sign, and it has proven to be. Had a small lightshow at the end of that 37°C heatwave, but nothing else of note.

I really think it's time we had a pub gathering to drown our sorrows!

[Lightfox]

Still no lightning here in plymouth; hopefully tonight’s the night ️

[camturbo]

1 hour ago, Ben Sainsbury said:

Quite like yesterday I think we will likely see a few surprises! I'm gonna be heading out myself today, maybe around the Yeovil area?

Let's hope it happens eh!! I'm not far from there 

[Vestan]

Spent last night on the west side of the IoW around Christchurch, expecting a good show & got absolutely nothing. Back home tonight where we could be on the edge of the action, but it should be another good evening watching the radar

[TomLO04]

Last nights antics:

Shelf cloud moving in

 

 

 

 

 

 

 

 

 

 

 

 

Edited September 5, 2022 by TomLO04

[Met.]

9 hours ago, Steel City Skies said:

Lots of lightning in the distance, great to watch coming in. Died out somewhat as the bulk of the precipitation came over. Still the odd flash.

The thunderstorm was pretty good in my area of south Sheffield. I watched it come in as well from the first flashes to the first creepy rumbles then the loud thunder as it passed overhead. 

[ChannelThunder]

10 hours ago, Southern Storm said:

Congrats to many on here that are enjoying a decent thunderstorm

This years storm season has been a strange one, started off well in May, not much in the middle.... and here we are in September  getting some decent action!

Unfortunately for me, the storms initiated a little bit too far east for me to get in on some decent action.

Plus I made the mistake of going west, when I should have gone east, but there you go that's life! 

I did manage to get some pictures with my 135mm and I'm actually quite happy with how they turned out 

Hopefully there will be more surprises in the coming days!

Congrats on those! I also had my camera pointed at one of our two TV masts (Chillerton) over here but didn't get so lucky! You've done really well there given the lack of CGs. There are more in your photos than I even saw with my eyes! I really messed up in terms of positioning etc which didn't help.

[Liam Burge]

38 minutes ago, A Face like Thunder said:

Yellow thunderstorm warning now issued for Western parts of England and Wales, the East Midlands and London & the SE, covering the period from 14.00 today to 02.00 tomorrow.

There goes my chance of a storm then!

[wimblettben]

Rubbish disappointing night here with all of the action many miles east of here of where it should have been. Thought it was just a general bust for the whole of the UK around 2:00AM only to find out when checking the forums that there was a huge line of activity over central England so not only was I upset but I was also envious.

We must have better chances this afternoon or this evening and night though surely, especially as we are in a 50% risk zone. 

Edited September 5, 2022 by wimblettben