Convective Outlook: Fri 09 Nov 2018
What do these risk levels mean?
Convective Outlook

VALID 06:00 UTC Fri 09 Nov 2018 - 05:59 UTC Sat 10 Nov 2018

ISSUED 20:49 UTC Thu 08 Nov 2018


The main interest during this forecast period will be during Friday evening and night as the next Atlantic frontal system sweeps across the British Isles. Upper forcing coupled with a strong low-level wind field ahead of, and marked wind veer along, the frontal boundary will be favourable for some elements of line convection to develop on the rear side of the precipitation envelope. In general, profiles look very saturated which combined with weak instability will significantly limit the potential for lightning - though a few isolated strikes cannot be ruled out. Main threat will be squally winds and bursts of heavy rain.

The post-frontal environment will then see cold air advecting over warm seas, generating 400-700 J/kg CAPE. Scattered showers will move across Ireland initially, and then other southern and western coasts of Britain late on Friday night. Some sporadic lightning and gusty winds will be possible, along with hail up to 1.5cm in diameter.