Convective Outlook: Fri 22 Jul 2022
LOW
SLGT
MDT
HIGH
SVR
What do these risk levels mean?
Convective Outlook

VALID 06:00 UTC Fri 22 Jul 2022 - 05:59 UTC Sat 23 Jul 2022

ISSUED 07:21 UTC Fri 22 Jul 2022

ISSUED BY: Dan

A rather slack pattern prevails on Friday, with an upper trough over the English Channel. This will likely engage with and encourage advection of a >16C 850hPa ThetaW airmass from France towards S/SE England. As such, elevated showers and perhaps a few thunderstorms could evolve over the English Channel during Friday daytime and drift towards S/SE England, albeit probably weakening soon after landfall. Tentatively introduced a MDT given the magnitude of elevated instability that could lead to quite frequent lightning (especially given the sheared profiles too), but confidence is not overly high.

Elsewhere, the other main area of interest is across N/C/E Wales down to the West Country, as a narrow corridor of 400-800 J/kg CAPE becomes established by the afternoon. This may provide the focus for a scattering of heavy showers, but skinny CAPE, generally weak speed shear (some directional) and some subtle warm noses aloft (given distance away from the main cold pool aloft over the eastern Channel) suggests a similar scenario to Wednesday may evolve with convection tending to spread out and struggle to produce much lightning activity. Nonetheless, slow-moving downpours will pose a risk of local surface water flooding. The slack humid flow may also be favourable for a few funnel clouds.