Ben Sainsbury

According to this article: There were 50knts of DLS equivalent to around 25m/s. 28th June 2012 STRATUSDECK.CO.UK For many people in the UK, including meteorologists and weather enthusiasts, June 28th 2012 was a day...

Yeah agreeing with much of the chat regarding next Thursday, general consensus is for a few home-grown elevated storms to develop across CS England and the far South. The risk generally to transfer eastwards with the potential for storms to root to the boundary layer to become surface based or for other surface based storms to form late morning across SE England and East Anglia. NMM generally tends to over-blow CAPE values but even then we are still looking at 1000J/Kg respectively. Decent DLS too as mentioned so chance of organisation and/or weak home-grown MCS as hinted by NMM. Steep lapse rates too so some quite frequent lightning at times. Though all subject to changes over the coming days.

Despite that ECM, UKMO & ICON all relatively similar at T144. GFS nah nah.

Wow, big difference at T96 on the ECM regarding the low SW of Ireland. Much deeper than GFS, UKMO & ICON.

Another reload of the Azores high advecting towards us And it's going to be real hot

ICON 18z at 120 much more amplified than its 12z run.

You can't judge where today's storms will be based on yesterday! Aha unfortunately it doesn't work like that.

Deep convection going up between Exmoor and Dartmoor as evident on Sat24.

Might actually be the best lightning display I've ever seen on a webcam.

I know this is somewhat more relevant for the European chat but storm initiation over N Spain into the Bay of Biscay taking place an hour or two earlier than expected. Unsure of what this means in regards to later.

Latest UKV run looks beefy that's for sure! Thunderstorm Advisory Issued by Metcheck: Metcheck.com - Latest UK Weather Warnings - UK Weather Alerts. WWW.METCHECK.COM Metcheck.com - Latest UK Weather Warnings - UK Weather Alerts.

Yep, Dan's forecast aligns well with my current thoughts. ESTOFEX forecast link too: http://www.estofex.org/ (Level 2 Issued for W France) Could be in the sweet spot if you live in Cornwall, UKV has thundery activity even reaching there tonight.

Very low risk tomorrow night < 5% of any activity inland, a front moving northwards tomorrow night into Tuesday still looks to produce an MCS/Squall Line in the Bay of Biscay but runs until much more stable air due to high pressure across English Channel/Coastal Southern Areas. Could be some great radar/sat/lightning watching for W/NW France but won't really know how far north the convective activity reaches until we get to the time. Still think there is a 20% chance approx of far SW Cornwall and maybe South Devon a chance of a few distant flashes but unsure as of yet. Bit disappointing really.

Must remember that ESTOFEX & Dan have different lightning risk criteria. ESTOFEX is 15% within 40km and Dan's 10% within 25km (on this occasion anyway).

The most unexpected of flashes outside my window from a small shower to my east!

Just to add onto my previous post about the thundery potential next Monday into Tuesday, here's what the current forecast models show atm: UKV actually shows the biggest chance of any thundery activity reaching the far SW. High-res models like AROME & EURO4 don't reach that timeframe yet. GFS: ARPEGE: NMM: UKV: ICON:

Not too much to talk about regarding potential thundery activity next few days. However still keeping a keen eye on developments Monday into Tuesday for the far SW England & S Coast of Ireland. Early signs for MCS development to take place over the Bay of Biscay and weaken on its approach to the SW, unsure whether it will even make landfall but hopefully those in the far SW may see some decent lightning/storm structure. Whilst CAPE values are a touch low, all the parameters are in place for quite a prolific MCS to develop. How far north the MCS reaches is dependent on how far the moist unstable air is advected northwards.

Have a feeling judging by T138 on GFS 18z that this could turn out to be a warm one!

Definitely aimed at much of France and Germany, they're expecting some enormous DLS values today >60knts.

Should actually see some semi-decent lightning activity as a result too!

GFS are definitely prone to over-blowing CAPE values particularly medium to long range but the CAPE values shown for early next week is nothing extraordinary and is actually supported by the ECMWF with a similar thundery breakdown. So in response I don't think the CAPE values in particular will water down too much it's just a case of whether all the right ingredients come together. The storms do appear to be quite active don't they! Even ESTOFEX have only issued a 15% risk for Northern France. Despite that there are 500-700J/KG of CAPE so it is no surprise that there is a fair bit of electrical activity but probably a little more than expected.

Looking ahead to next weekend/early next week there appears to be a lot of potential for some strong/severe thunderstorms across Southern areas. Just for a laugh I decided to look at some of the available charts: Quite extraordinary what the latest GFS run has in store and I must stress this is likely to be changed/watered down. But for early Monday a large amount of moisture is advected northwards across S UK, 850hpa temps reaching 15'c in the SE which allows 800J/KG of ML CAPE to develop. Followed by 40knts of DLS and very steep lapse rates this is simply all the ingredients required to spawn a few severe elevated thunderstorms. GFS actually hinting at quite a prolific MCS to move NNE across CS England Monday morning. I better stop myself before I get too excited but for those new, what the GFS is currently showing for next weekend is typically what you require for a severe thunderstorm outbreak. If any of you have any questions then feel free to ask. I'll be keeping an eye on these developments over the coming week.

Would not look at the latest UKV run if I were you guys... Done well regarding today's storms too.

Quite a potent little feature moving over Sidmouth, SE Devon right now. Would expect to see some further development just west of Poole in the next hour.

Judging by the cloud heights on Sat24, radar & lightning tracks I think there is a good chance that the areas of storms around Jersey will merge to form a larger (but relatively weak MCS) moving between the Portsmouth to Brighton area between 10pm and midnight.