Overview

• The warning runs from midnight to 2pm on Wednesday and covers London and the South East, the South West and much of Wales.
• Forecasters expect 20–30 mm of rain widely with isolated 40–60 mm in 6–9 hours, plus thunderstorms and a spell of coastal gales along English Channel coasts.
• Met Office guidance shows gusts near 50 mph in parts of the South West and around 43–45 mph in areas of Wales such as Swansea and Cardiff.
• Officials warn of longer journey times on roads and public transport, a risk of flooding for a few homes and businesses, and possible power interruptions.
• Outlooks highlight a shift to changeable, Atlantic-driven conditions after the UK’s warmest summer on record, with one service reporting a limited risk of brief tornadoes in parts of England.