Convective Outlook: Mon 12 Mar 2018
What do these risk levels mean?
Convective Outlook

VALID 06:00 UTC Mon 12 Mar 2018 - 05:59 UTC Tue 13 Mar 2018

ISSUED 21:49 UTC Sun 11 Mar 2018


Upper and surface low move slowly eastwards across southern Britain on Monday. Numerous bands of showery rain will rotate around the low centre across much of England and Wales, but any sufficient heating given cloud breaks will steepen lapse rates to allow a few slow-moving heavy showers to develop, some electrified.

Lightning risk looks greatest in a narrow curved corridor where low-level convergence is maximised from W Norfolk/The Fens through Cambs / W Essex / Herts / London / Kent / Surrey / Sussex etc, but confidence not high enough to upgrade to SLGT for now given marginal instability, saturated profiles and extensive cloud cover possible. Nonetheless, slow-moving nature of heavy showers could lead to some localised surface water issues. Such setups can produce a few funnel clouds or weak tornadoes.