Overview

• Yellow warning runs from midnight to 2pm Wednesday for London and the South East, the South West and much of Wales.
• Forecasters expect 20–30mm of rain widely with some spots seeing 40–60mm in 6–9 hours, plus a risk of thunderstorms and hail.
• Coastal gales are likely for a time along English Channel coasts, with gusty conditions affecting the morning commute and school run.
• The Met Office warns of possible flooding, longer journey times, and brief power interruptions, advising checks on flood risk, travel plans and an emergency kit.
• The Environment Agency has issued flood alerts in parts of Devon, while a private forecaster notes a low‑confidence risk of brief tornadoes in isolated areas.