Ben Sainsbury

ECM 12z hasn't fully rolled out yet?

A pick of the charts as you might say but NMM 12z is an absolute treat for N England. Not meant to post too many of these charts but helps create the picture. Can't get much better for the UK. Friday evening, classic loaded gun setup, large CAPE, large DLS environment. Cap broken late evening which would result if some isolated but very significant thunderstorms. Some severe with a supercell or two likely. Obviously pick of the charts this evening and a bit of eye candy, but is one of the options out there.

Looks like a better GFS 12z already. Better jet profile, means pattern is a little more amplified and the low S of Iceland struggles to link up with the Iberian low. Hopefully get a slightly warmer & more prolonged southerly flow here.

GEFS 12z out till Friday evening for London, 850s are over half a degree warmer than the 6z. Mean peaks at 16.5'c, so corresponding to low 30s at the surface. However, does seem to be a bit of a split emerging into Saturday between those that become significantly cooler quickly and those that stay warm. The majority of the ensembles stay warm into Saturday currently.

Admittedly the GFS 12z not quite as good as previous runs, but that's fine as small differences are expected at this range. The key thing here are the ensembles, before throwing toys out the pram if you're after extreme heat that is!

For what its worth the NMM 12z has 23'c at 850hPa early on Friday, leading to 34'c maybe 35'c locally on Friday afternoon.

On another positive note too, am posting from mobile so no photo but GEFS 6z is an improvement on the 850hPa mean compared to the 0z.

This is not something I'm too bothered about at this range. Let's just get the heat in first and see what happens as often in these setups, thunderstorms don't appear in the hi-res models until we're at very short ranges. Classic loaded gun setup looking likely, where all it takes is enhanced convergence or increased moisture to kick off a beast!

Small CAP in place likely due to dry mid-levels, hopefully next few hours we can see some deeper convection developing and so more lightning.

Could be a decent little day tomorrow with widespread heavy showers/thunderstorms. Assuming swift clearance of the occluded front tomorrow then could be one of/the most active day this year. GFS/ICON/ARPEGE have 500-700J/kg of CAPE locally, the higher res models of UKV/AROME/NMM have up to 1,200J/Kg locally which is quite significant actually with relatively steep lapse rates. Only downside tomorrow is non-existent shear across much of England/Wales. Area of focus to me likely Lincolnshire region, region of largest CAPE, poss enhanced low-level convergence and vorticity, maybe resulting in non-zero directional shear for a time too. Looks somewhat similar to 31st May of this year, but possibly a little more active/widespread.

Despite some of the recent elevated thunderstorm events not always going to plan... As it stands, the far S (particularly CS England) have fared quite well for elevated thunderstorms coming off the near continent, especially given it's only the start of June. Maybe some correlation with above average SSTs? But given it's only June I expect it's a matter of time until we see more widespread surface-based potential developing, so I wouldn't be too disheartened yet if you haven't seen much in the way of activity!

Been very busy tonight but just checked the radar & wtf is going on! All the action is away from the SE haha

UKV 9z doesn't seem all that different to previous runs to me. MUCAPE much larger and makes it further northward which is a big positive imo.

Definitely cannot be surface-based CAPE, even if says on the title of the chart, that’s odd…

Lack of model agreement indeed, majority of the models focus CS England tomorrow night, ECM at the moment appears to be a bit on its own. Tonight for comparison seems considerably lower instability, but still respectable (300-500J/Kg). However, DLS appears to be quite strong tonight so multicell clusters are still likely to develop, but frequency of lightning is still to be determined maybe more akin to 15th May of this year. In response to @Lance M & @Azuremoon2, so far I see no indications really of this being a France/Kent Clipper scenario but obviously this may change. Also, with import events like this I would expect developments to take place over the channel regardless of if the models or UKV in particular are showing it. That saying the UKV performed exceptionally well on May 18th so that is also something to consider, especially regarding westward extent of lightning.

I think tomorrow night has a lot more potential than some are suggesting. Trough embedded in the flow moving northwards along with high Theta-W. Interaction with upper low and cold pool will generate instability up to 1,000J/Kg and steep lapse rates. A portion of the jetstream heads NE over SE UK, generating 30-40kts of DLS, so multicells likely tomorrow night with the possibility of upscale into an MCS/Squall Line again. To me ingredients seem similar to that of May 18th.

We do now!

Some deep convection kicking off W of the Channel Islands judging by Sat24. One heavy shower may have just produced the odd strike. IF initiation takes place W of the Channel Islands, then this is further west than I expected.

Just shows that none of the models can be trusted to be honest

ESTOFEX are a team of very talented forecasters but as they focus on Europe as a whole I feel like sometimes they can miss out a fair bit of local detail, so I’d pay more attention to the text rather than the chart.

Good to see a number of people out chasing today! Hopefully, might run into one or two of you at some point

Elevated thunderstorm events are notoriously hard to predict. The majority of the models do look impressive even for regions within our SLGT zone. We’re just uncertain on the NW extent of any lightning, so maybe we’ve been a little conservative with our forecast so we’ll have to see. The key thing to note is; it’s not that SE England/the Channel will see more lightning, it’s more of a case of this region just being at a higher risk of lightning.

UKV 0z still looking nuts, it’s such a relief to see that this is all still there and hasn’t disappeared overnight

Looks like a good shout that, definitely something I'll consider tomorrow. One thing regarding the storms, whilst they look to move quickly NE, as typical with these events I would imagine cells to continually develop on the S/SE flank in the region of highest instability and higher Theta-W (something which isn't always well picked up on the models). So I'm hoping I won't have to track NE along with the cells and rather just watch new cells develop on its S flank whilst gradually relocating east.

Will be going chasing tomorrow, from my location in Bristol atm. Despite the westward corrections, I think I'm going to position myself maybe as far east as Brighton given past events. But maybe position closer to Portsmouth should developments happen further west. Does appear tonight to be a distinct split in the developing squall line/MCS, so the possibility of one system moving across CS England and the other much later in the night across the SE.