London Marathon weather: Weekend's race could be hottest on record with temperatures expected to reach 22C, says Met Office

Runners to battle heat as forecasters warn temperatures could climb past 22.7C record

Runners make their way off Tower Bridge during the 2017 London Marathon (PA Wire/PA Images)

This weekend’s London Marathon could be the warmest on record, forecasters have said.

Runners will tackle the race in expected temperatures of 22C, according to the Met Office.

Temperatures could even climb higher than the 22.7C recorded in 1997, the year of the hottest previous marathon.

“There is a chance that we could be looking at the warmest marathon,” said Met Office spokesman Oli Claydon.

But he said there could be respite for runners in the form of showers on Sunday afternoon.

This week’s soaring temperatures are expected to continue through the weekend after peaking at 25C on Thursday, forecast to be the hottest day of the year so far.

Marathon organisers said they had “contingency plans” for hot weather.

In 2007, organisers installed run-through showers at four points along the route and stocked each water station with 27,600 bottles.

Whether temperatures on Sunday rise as high as 11 years ago is likely to depend on cloud cover and rain, according to Mr Claydon.

He said: “We’re looking to start the day dry and bright.

“There could be some heavy showers developing from the west; it’s uncertain what progress they will make across the country and whether they’ll actually reach London during the day.

“I suspect the elite runners starting in the morning will escape those showers but there is a chance of one or two showers creeping in during the afternoon. They will be showery in nature rather than prolonged heavy rain and it will be dry, bright and sunny before that.

“There is a chance that we could be looking at the warmest marathon, but equally we’re looking at the possibility of some showers moving in which would interfere with that 22.7C being reached.”

A 22-year-old man died after collapsing during the 2007 marathon. St John Ambulance treated 5,032 runners throughout the day, with 73 requiring hospital treatment.

The Queen will start this year's race at 10am on Sunday, with Britain's Olympic 10,000m champion Mo Farah among the elite runners tackling the 26.2-mile route.