|Convective Outlook: Tue 15 Sep 2020|
|What do these risk levels mean?|
VALID 06:00 UTC Tue 15 Sep 2020 - 05:59 UTC Wed 16 Sep 2020
ISSUED 07:53 UTC Tue 15 Sep 2020br> br>
ISSUED BY: Dan
Rex block pattern dominates Europe through Tuesday, characterised by a strong upper high over central Europe and an upper low over the Mediterranean. Trough disruption over the Atlantic will result in a second upper low sinking south to the west of Iberia. An upper ridge generally covers the British Isles through this forecast period, with a broad south/southwesterly flow aloft, advecting a marked elevated mixed layer (EML) across much of England and Wales. A PV strip is noted curving from E Scotland - SW Scotland - Irish Sea - SW England at 06z, the focus of this strip will then shift gradually eastwards to be positioned around SE Scotland - NW England - Wales - SW England by 12z, then NE England - Midlands - Cen S England by 18z and finally E Midlands - E Anglia - SE England by 00z. This may induce some weak forcing aloft, above / around the periphery of the EML, to bring the risk of a few semi-random elevated showers / weak thunderstorms. Since these are not dependent on surface heating, they could occur at almost anytime during this forecast period. However, guidance is not particularly bullish in this risk and so a broadbrush LOW threat level has been issued given the vast majority of places will remain void of any lightning activity.