Muddy mayhem could make an unwelcome return at Glastonbury Festival this week, forecasters warned today.
Wellies and rain coats will be essential packing as more than 170,000 campers arrive at the Somerset site from Wednesday.
With the Worthy Farm land already drenched after heavy rain in recent weeks, a repeat of last year's heatwave has been ruled out.
Matt Dobson, forecaster for MeteoGroup, the weather division of the Press Association, said revellers should be spared extreme downpours which have infamously blighted some years.
But he added: "The famous mud will make an appearance."
Revellers arriving on Wednesday will be putting up their tents in "cool and breezy" conditions "with a few showers around".
Thursday and Friday could see sunny spells, with temperatures around 18 or 19C.
Saturday will start off dry before turning wet while Sunday could be quite "muggy".
U2, Coldplay and Beyonce headline - but this year's Glastonbury "moment" could be a tomato fight.
Festival founder Michael Eavis's pride and joy is a new medieval bullring - Campo Pequeno.
The 75-year-old farmer said the arena is "my real baby this year".
Among a host of theatrical events at the site will be Glastonbury's own version of La Tomatina.
Eavis added: "Campo Pequeno - fantastic. Building the thing now, seeing it all come together with everyone around. That's the best bit for me."
Other new elements for this year include The Spirit of 71 stage, with acts that played at the festival 40 years ago.
Beyonce, who fell in love with the Somerset festival after watching husband Jay-Z perform three years ago, is believed to have cleared her diary to party in Pilton over three days.
When asked whether Jay-Z would be joining her on the Pyramid Stage, Eavis said: "Wouldn't it be nice? When he came before it was an absolutely fantastic success and in a way that's what persuaded Beyonce to come and do it. She was here before, saw the amazing response from the crowd."
The headliners' bill, which also includes U2 and Coldplay, is a far cry from the festival's hippy beginnings but Eavis said the introduction of urban acts had been a "tremendous period for us".
He said the event was a "microcosm" for every interest.
Glastonbury, which sold out this year in four hours, takes a year off next June to rest the 500-acre dairy farm's land.
"We are going to travel around the coast," Eavis said. "We have a little yellow Mini with a black top so if you see us in Carlisle or Great Yarmouth, it's me and my wife."