Londoners have been caught in delays on the Tube as they return to work bleary-eyed after another tropical night.
London has served a dose of reality to commuters returning to the office after the sweltering bank holiday weekend, with delays across the Underground network and soaring temperatures.
Mercury is approaching 26°C before 9am, spelling another blistering day in the capital.
The worst-affected are the District, Piccadilly and Central lines, while the Circle and Hammersmith & City lines have minor delays, the latest TfL travel status shows.
The District line is reporting severe delays on the entire line due to the late finish of engineering works.
The Piccadilly line is impacted by the same issue this morning.
The Central line is seeing severe delays in both directions between North Acton and Ealing Broadway, North Acton and West Ruislip, Epping and Leytonstone and Hainault and Leytonstone because of train cancellations.
Passengers can use tickets on buses, the Elizabeth line and the South Western Railway services.
Delays on the Central, Circle and Hammersmith & City lines are because of train cancellations, TfL said.
How to stay cool in a heatwave
If you have to travel on the Tube, train or by road this week, have plenty of water at hand and dress in cool, loose-fitting clothing if possible.
Reaching for a sip of water in any weather is not a bad idea, but doctors have recommended one surprising everyday drink in a heatwave.
On the Tube, your best hope is an Underground line with air conditioning.
Metro has this handy guide for heatwave survival 101 shopping essentials, from best handheld fans to cooling pillows.
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