Convective Outlook: Sat 18 Mar 2023

LOW SLGT MDT HIGH SVR

What do these risk levels mean?

Convective Outlook

VALID 06:00 UTC Sat 18 Mar 2023 - 05:59 UTC Sun 19 Mar 2023

ISSUED 07:10 UTC Sat 18 Mar 2023

ISSUED BY: Dan

The upper trough over Ireland on Friday will be centred over Britain on Saturday, the cool air aloft atop modest heating of a moist low-level airmass creating an unstable environment by the afternoon and yielding a few hundred J/kg CAPE. However, under the axis of the upper trough shear will be rather weak leading to pulse-type convection with a scattering of heavy showers, perhaps a few isolated lightning strikes but unlikely to be as active as the past couple of days. A frontal wave will bring cloud and more widespread rain to parts of SE England and East Anglia through the day too, and this could linger well into the afternoon / be more widespread than model expectations, and so the area with the best potential for heavy showers and isolated lightning will be from Wales across the Midlands and into northern England. Tentatively issued a low-end SLGT to highlight the region with better potential. A few heavy showers will also be possible in southern England in response to low-level convergence as skies brighten during the afternoon.