Oct.16 (GMM) F1 looks set for a third consecutive grand prix that is affected by rain.

After the Fuji washout and the wet-dry Chinese grand prix two weeks ago, forecasters are now predicting a weekend of potentially changeable weather in Sao Paulo; scene of Sunday's 2007 title showdown at the Interlagos circuit.

Rain has been ever-present in the Brazilian city all week, but weekend forecasts predict that the weather should by Sunday be in the process of clearing up.

Williams' debutant racer Kazuki Nakajima, however, said in an official team preview on Monday: "It looks like it's going to rain over the weekend."

The British team's technical director Sam Michael added that the weather forecast "is currently predicting rain all weekend" for Brazil.