London's sweltering heatwave has been replaced by a new threat: thunderstorms are forecast to hit the capital on Thursday afternoon, with three days of disruption expected to follow. The Met Office has issued a yellow weather warning for thunderstorms, effective from 15:00 BST on Thursday, 20th June, and extending through to Sunday, 23rd June.
The Met Office warns of heavy downpours, lightning, and strong gusts of wind, which could lead to localised flooding, difficult driving conditions, and possible interruptions to power supplies and public transport services. Forecasters say the storms will develop as warm, moist air interacts, creating unstable atmospheric conditions conducive to thunder and lightning.
Temperatures in London are expected to remain relatively warm during the stormy period, hovering around 23-24°C, which could contribute to the intensity of the downpours. Wind speeds may reach up to 30 mph in gusts during the heaviest storms.
While London faces the most immediate threat of prolonged thunderstorms, other regions are also bracing themselves for unsettled weather. Northern Ireland and Scotland expect a mix of sunshine and occasional light showers, while Wales and parts of England may experience isolated thunderstorms – though not with the same sustained intensity as forecast for the capital.
The Met Office advises residents to take precautions during the warning period. This includes securing loose outdoor items, avoiding unnecessary travel, and being aware of potential flash flooding on roads. If driving, motorists should slow down, use headlights, and be prepared for sudden changes in road conditions due to standing water or spray. Staying indoors during lightning storms is also strongly recommended.