London Marathon runners can expect glorious sunshine and warm weather in the capital this Sunday, the Met Office predicts.
The 2025 edition is set to become the world's largest marathon, with more than 56,000 people expected to finish this year's race.
Race day in the city will begin on a cloudier note, with some light winds during the morning and early afternoon.
Temperatures of 10C (50F) are predicted when runners set off in waves at the start line in Greenwich Park.
Did you know...
Last year’s New York Marathon holds the world record for the largest marathon, with 55,646 runners crossing the finish line in Central Park
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Elite wheelchair races are set to begin at 8.50am, followed by elite women at 9.05am, elite men at 9.35am, and then the mass event from 9.35am to 11.30am.
However, brighter conditions are set to move in from the west as runners pass many of London’s most iconic sights: from Cutty Sark and Tower Bridge, to Canary Wharf and Big Ben.
The mercury could be as high as 21C as runners head into the final stages of the race and cross the finish line on The Mall in St James’ Park.
After a miserable end to the Easter Bank Holiday, which saw thunderstorms hit parts of Britain, the weather has been distinctly changeable this week.
Friday is expected to be fine at first, but the sunny intervals will turn increasingly hazy under advancing clouds, heralding a spell of rain into Saturday.
Met Office meteorologist Dan Stroud said the unsettled conditions is “welcome news”, as the average rainfall figure for April nationally is 71mm but the UK has only had 27mm so far.
He added: “Changeable probably sums it (the weather) up nicely.
“The rain is going to be fairly welcome news for the gardeners, because it’s been actually very dry up until now.”
See also: How running a marathon impacts your body
Temperatures are predicted to rise markedly next week, with the Met Office forecasting 22C in London on Monday, and 24C on Tuesday, Wednesday and Thursday.
That would represent the warmest weather stretching over a number of days so far this year.
The UK has had one of the worst wildfire seasons on record.
The rain is going to be fairly welcome news for the gardeners
At the start of April, the London Fire Brigade received 2,200 calls — more than 200 per cent more than the same period last year.
These included 65 outdoor fires — in woodland, parks and gardens as well as involving shrubbery, trees and logs — which was an increase from 15 in the same timeframe in 2024.
Next week will see a “mini-heatwave”, with 23C (73F) temperatures predicted for Monday and Tuesday.
The Met Office added: "It will most probably be high pressure dominated, with large amounts of fine weather. Any more unsettled interludes liable to be brief and mainly affecting western or northwestern UK."
