Festival-goers arriving at Glastonbury today and tomorrow should expect to get wet and muddy as heavy showers are expected by the weekend, weather forecasters have warned.
The recent fine spell is set to break at the end of the week and the predicted rain could turn the festival into a mud bath as thousands of revellers tread the site.
John Griffiths, a forecaster with Meteogroup, said: "If it was just a few showers the hard ground would make it drain off. But after three days worth of rain it will probably get quite muddy, I suspect."
Those travelling to the festival are advised to bring wellies and waterproofs and be prepared for the rain.
Mr Griffiths said today and tomorrow will be cloudy with sunny intervals and temperatures of around 20C (68F), while at night it will drop to around 10C or 11C (50F or 51.8F).
"Friday is when it starts to look a bit worse," he said. "There will be showery rain and there might be a little bit of thunder in the evening.
"Saturday looks like it's going to be cloudy with a few showers but these are going to get more frequent in the evening.
"Sunday there will be showers throughout the day but there may be the odd sunny spell."
Organisers will be hoping not to have a repeat of some of the wettest Glastonburys when tents have become submerged and the site has turned into a quagmire.
In 2005 the start of the festival was delayed by heavy rain and thunderstorms and flash flooding left some of the site 4ft under water.
The muddiest year was in 1997 when 78mm of rain fell eight out of nine days in the run-up to the event.
The Met Office has also predicted rain.
Deputy Chief Meteorologist Bob Wilderspin said: "Thursday night into Friday morning could see some heavy downpours for Somerset and there is the potential for slow moving thundery showers to affect Glastonbury Festival both Saturday and Sunday."
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