More than 40,000 athletes and spectators are hoping for perfect weather conditions as the London Marathon is staged on Sunday.
The 26.2-mile course will take elite runners, including Olympic gold medallist Mo Farah, and the rest of the field from Blackheath in south-east London to The Mall, near Buckingham Palace.
It will be held a day after Storm Hannah battered much of the UK with 82mph winds and heavy rain, and a year on from the hottest London Marathon ever.
Sunday's conditions could be ideal for the gruelling challenge as the Met Office predicts cool temperatures, some cloud cover, a light breeze and a chance of light rain.
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Temperatures in London will be 9-10C when the races begin from 9am, and will warm to 12C by noon and 14C by 3pm, a week after a 26C Easter heatwave.
They are expected to peak at 16C.
There will be a light breeze, about 12mph, from the north-west with winds gusting to about 24mph at times.
The Met Office is predicting a chance of light rain between 11am and 2pm, with otherwise cloudy skies and some sunny intervals along the route.
UV levels will be low to moderate and the pollen count will be high.
In its forecast for London and the south-east, the Met Office said: "Generally cloudy start to the day, then bright or sunny spells gradually developing.
"Many places will remain dry, although there is a chance of a few showers through the morning and early afternoon."
England marathon coach Tom Craggs told Fast Running “it’s ideal weather conditions for a marathon with around 10-13 degrees during the race".
He added: "Although there will be a light headwind in those final miles it won’t be enough to make a difference.
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“After last year’s hot weather there will be no excuses this weekend ... it’s going to be perfect for some fast running and we can all be hopeful to see some PBs (personal bests).”
The elite wheelchair races begin just after 9am, followed by the World Para Athletics Marathon Championships ambulant athletes.
At 9.25am, the elite women's race will get under way, and it will be followed at 10.10am by the elite men's race, the British Athletics & England Athletics Marathon Championships, and the mass race as thousands set off to raise money for charities.
Tennis champion Andy Murray will start the proceedings.
Celebrities running the marathon include radio DJ Chris Evans, Great British Bake Off winner Candice Brown, TV presenters Kirsty Gallacher and Mark Wright, and the BBC's Helen Skelton.
The 2018 marathon was the warmest ever with a temperature of 24.1C at St James's Park.
