Chiswick forecast: 33°C today with a 65% chance of rain and storm risk
27 June 2026 · By Boroughly editorial — AI-assisted, human-reviewed.
After a week of extreme heat, today brings a slight dip — but conditions remain demanding and potentially unsettled. The Met Office is forecasting a high of 33°C for Chiswick on Friday 27 June, with a low of 21°C overnight. The UV index stands at 7, still firmly in the "high" band, so sun protection remains important if you are outdoors. Met Office forecast
The more significant change today is a 65% chance of rain, with storms flagged as a possibility. After several days of dry, building heat, any downpour could be heavy and fast — worth keeping an umbrella to hand and being cautious if cycling.
The hot weather is already affecting local transport: TfL is running reduced and slower services on several lines as part of heat mitigation measures, compounding the weekend engineering closures on the District and Piccadilly lines.
If you are heading out, earlier in the day is likely safer and more comfortable. Hounslow's health guidance during heat periods advises keeping homes cool, staying hydrated and checking on elderly neighbours.