Convective Outlook: Thu 06 Jan 2022
LOW
SLGT
MDT
HIGH
SVR
What do these risk levels mean?
Convective Outlook

VALID 06:00 UTC Thu 06 Jan 2022 - 05:59 UTC Fri 07 Jan 2022

ISSUED 08:20 UTC Thu 06 Jan 2022

ISSUED BY: Dan

Behind an eastward-moving occlusion, which may contain some elements of shallow convection, a substantial cold pool will overspread the UK and Ireland later on Thursday and overnight into Friday as an upper trough arrives from the Atlantic. This, coupled with relatively warm SSTs will yield a few hundred J/kg CAPE. Forecast profiles reveal potential for deep convection to reach a rather low tropopause (400mb). The strongest shear will be primarily around the periphery of the upper trough, and so mostly across southern Ireland and towards SW England, with weaker uni-directional flow with height further north towards Scotland. Nonetheless, numerous showers are expected to develop over open seas and migrate inland on the steering flow, and it seems plausible a few sporadic lightning strikes may occur at times - hence a low-end SLGT has been introduced.

Odd showers will be possible just about anywhere at some stage on Thursday night, with an associated low but non-zero risk of lightning, but the risk will always be highest generally in the west. Some convergence through the Bristol Channel for a time could pose a slightly higher threat here perhaps. Hail and gusty winds will accompany some showers, the strongest gusts of 50-70mph likely in western Ireland, and later in the night towards SW England. Within the belt of stronger flow aloft from southern Ireland to SW England this may be sufficient for some updraft rotation, however convection will tend to be shallower with weaker CAPE.