Convective Outlook: Fri 09 Jun 2017
LOW
SLGT
MDT
HIGH
SVR
What do these risk levels mean?
Convective Outlook

VALID 06:00 UTC Fri 09 Jun 2017 - 05:59 UTC Sat 10 Jun 2017

ISSUED 20:11 UTC Thu 08 Jun 2017

ISSUED BY: Dan

As a sharpening upper trough clears eastwards across Britain on Friday, so the main forcing for ascent will shift east and exit across the North Sea. The trough is characterised by relatively steep mid-level lapse rates, and should help yield 300-600 Jkg-1 CAPE in response to modest surface heating. Some sporadic / isolated lightning may be ongoing at the beginning for the forecast period over western portions of the LOW threat level, with the area of best convective potential gradually shifting eastwards through the day.


A couple of thunderstorms will be possible over eastern Britain late morning into the early afternoon as phasing of upper trough overlaps somewhat with diurnal heating - but with the trough then moving over the North Sea, a decrease in potential (and any lightning activity) is expected from mid-afternoon onwards as warming and ridging aloft overspreads the area ahead of the next Atlantic system. Overall lightning activity is not deemed high enough to warrant a SLGT at present.