Heavy showers are forecast for London on the day of the Olympic opening ceremony.
While Danny Boyle's ambitious plans for the opening ceremony include clouds that will rain down over the stadium in Stratford, east London, fingers had been crossed that the much-anticipated event would otherwise stay dry.
After weeks of wet weather the outlook has brightened up for the coming week.
The mercury is set to rise to 29C (84F) on Tuesday, and will stay in the high 20s for the rest of the week but forecasters said temperatures are set to fall again by Friday.
Billy Payne, a forecaster with MeteoGroup, the weather division of the Press Association, said: "Tomorrow is looking to get up to 27C in the South East and it will be dry, hot and sunny in most parts of the country apart from the North West, where there may be some showers.
"Tuesday will be more of the same and could get up to 29C in the London area.
"Towards the end of the week it is going to get a lot cooler and more unsettled.
"It looks as though there's a risk of heavy showers, certainly in the south-east corner of the country."
Widespread flooding, the wettest period of April to June on record and more heavy rain so far this month have been caused by the jet stream settling unusually far south.
But forecasters said it is on its way back north, leading to more traditional summer weather this week.
Bookies have been taking bets on what the next few weeks will bring, with William Hill offering odds of 3/1 that it is raining during the opening ceremony and 66/1 that the Olympic flame is extinguished while the last person carries it into the stadium.
They are also offering 12/1 that a temperature of more than 100F (38C) will be registered in the UK while the Games are taking place.
William Hill spokesman Rupert Adams said: "There can be little doubt that the British weather will have its say at the Olympics, most likely it will be wet but we could be in for a scorcher."