The Met Office has revealed bad news for London Marathon runners and viewers alike as it’s set to pour with rain. Meteorological maps shared on the UK’s national weather service’s Twitter shows a deluge of rain hitting the capital throughout tomorrow (April 23).

This is terrible news for those supporting the side-lines for friends and loved ones to complete the race who may well get soaked. However, it may be most welcome by the runners who might see the downpour as an opportunity to cool off during the 26 mile bonanza.

The chart shows what appears to be constant rain from 6am until 2pm. The full upcoming London forecast can be found below.

READ MORE: London Marathon live: Route map, timings and road closures as tens of thousands of runners race through city

According to The Met Office, today (April 22) will be ‘dry at first, with low cloud, mist and fog soon clearing to bright or sunny spells. Isolated showers may develop, especially across Hampshire, but most places will remain dry. Maximum temperature 13C’.

Tonight will be ‘becoming mostly cloudy with outbreaks of rain, locally heavy, arriving this evening. Later most places become dry, with low cloud and mist perhaps forming. Minimum temperature 7C’.

Bring an umbrella this Sunday if you're heading to the marathon

Tomorrow (April 23) won’t be much nicer, with the predicted deluge of rain set to drench London. There will be ‘rain, often heavy, quickly spreads north through the morning. Later the heavy rain may become generally confined to northern areas, while further south brighter and drier conditions develop. Maximum temperature 14C’.

From Monday (April 24) through to Wednesday (April 26) it will be a slight improvement, although nothing amazing. ‘Overnight rain clears Monday, then mostly dry and cloudy. Tuesday is dry with sunny spells and light winds. Wednesday is cloudy with outbreaks of rain, although some eastern areas may stay dry.’

For more London Marathon news and explainers, click here.

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