Teams will have to cope with a rain-hit practice session as the British Grand Prix weekend gets underway.
But forecasts say conditions will improve as the weekend progresses.
A low-pressure system to the wet of Britain is sending showers across the country.
A fresh band will head towards Northamptonshire early on Friday morning. Showers will return throughout the day to douse the track.
Stiff breezes are also likely at the exposed airfield circuit.
The rain will become less frequent as the weekend goes on. Temperatures should also climb above 20C.
But with the threat of showers hanging in the air, teams will need a pair of eyes glued to the weather radar images to gauge whether qualifying or the race will be affected.
The last wet British Grand Prix was in 2008, and won by Lewis Hamilton.
Silverstone weather radars
Location of Silverstone
View F1 race locations 2011 in a larger map
2011 British Grand Prix
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- Vote for your British Grand Prix driver of the weekend
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- Renault: Heidfeld salvages points from poor weekend
- Mercedes pass Renault in the championship
- Force India squander points chance
- Sauber: Perez claims best-ever result
- Toro Rosso: Alguersuari battles Buemi for point
Image ?Ú?« Red Bull/GEPA