Epic multicell thunderstorm - west Cornwall

[Graham Easterling]

It's been going on for hours now, as various cells move across. So far

06:45   Distant thunder as cell moved westwards just to the south.

 07:45   First rumbles of main storm

 08:30   Completely calm, very dark, thunder closing in, flashes now clearly visible

 09:00   Wind increased from near calm to briefly a F6 SE in < 1 minute. Very heavy rain,                  Close thunder.

 09:45   More close thunder, just to the north this time. Rain intensity increased again

 10:15   Quieter spell, rain eased off, just a little distant thunder

 10:30   More close flashes.

 11:00   More very heavy rain

Most of the intense activity seems to be on the north/east flank of the staorm

09:05

Nearly 2 hours later - 1050

Lightning

(Image just before the main storm hit, lightning an hour or so later)

Still a couple of cells with lightning to the south! Absolute classic, Tudor would love it.

Graham

Penzance

[Keith (Southend)]

So different to here in Southend-on-Sea, where we have warm sunshine 20.6°C atm.

Keith (Southend)

[Graham Easterling]

I checked the Penzance forecast a few times this morning, and the highest chance of rain when I looked at 08:00, just as the big storm loomed. was 50% at 11am. Still waiting for the rain to stop.

Now noon, they have raised the rain risk for now (noon) to 70% from 30% an hour ago - just one rain drop though. Forecast temperaure for now 17C (was 18C an hour ago) It's torrential again & 13C. It was 16C at 08:00.

Last thunder was about 20 minutes ago, and clearance now visible.

Great fun!

Graham

[Tudor Hughes]

Hello, Graham.  I was spoilt for life thunderstorm-wise by the events of 5 Sept 1958 when I was an impressionable 15. I've never seen lightning like it!  The nearest gauge to me had about 55 mm in 50 min.

         I would have loved to have seen your storm because there has been "no weather" here.  Max 22, light easterly, lots of dirty haze but not even the faintest rumble.

Tudor Hughes, Hamsey Green, Warlingham, Surrey, 557 ft, 170 m.

[Graham Easterling]

Back on 2nd June 1982 I recorded 90.2mm in 2 hours in Wootton Basset (pre 'royal' days - it wasy the most boring, unexciting & right wing place I've ever lived.). Nearby Lyneham recorded <1mm. It was an extremely narrow N-S aligned event. 

I let the MetO know, I received a letter back saying they were extremely interested in reports of this type and saying it was very rare on the Bilham Scale. A chap popped around to view my site, handed me copies of satellite imagery (novel in thos pre internet days) and I was included in the monthly hydrometeorological bulletin. How times change, it would be a miracle to get a vague acknowledgement these days.

The only time I can say I've been a bit scared by the weather was on the top of Striding Edge on Helvellyn when a thunderstorm rapidly developed & passed overhead. We found a ledge to shelter under, but before every flash there was St Elmo's fire and the covering of hail made a high pitched hissing noise, so you knew there was to be a virtually overhead flash before it happened.

There are some good pictures of the cloud formation just ahead of yesterdays storms, unforfnately largely hidden in Penzance by misty low cloud. Here's one from Redruth

Graham

Penzance