We've recorded the temperature onboard a 38 bus between Grays Inn Road/Holborn and Essex Road, Islington this afternoon. Our Political Correspondent Simon Harris's tweets accompany each image.
On Friday, the Mayor Boris Johnson promised to fix the problem, and Transport for London claimed an 'army of engineers' would work throughout the weekend to get the air conditioning working.
But many commuters have complained that the top deck of the new bus for London is still "unbearable"
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As Britain basked in the hottest day of the year (so far), the Met Office sent a warning which took us all by surprise.
James Davis, Laurence Halsted and Richard Kruse make up the squad. Marcus Mepstead is named as the team reserve.
After this morning's fire at Vauxhall 4 of the 8 lines are still closed which means South West Trains is running a limited service.