Teams are bracing for what looks like a very wet weekend in Shanghai, with rain forecasted for Friday and Sunday's 56-lap race.
Teams and drivers, but not all, sampled Pirelli's new wet weather tyres at a day of dedicated wet running in Barcelona during pre-season testing.
But the limited mileage may not be of much help if cars take to a wet track tomorrow for free practice.
Rain is forecasted throughout Friday with temperatures between 15° and 18° C, a level which cit affect tyre performance even in dry conditions.
Saturday is earmarked as a dry day by weathermen but rain is scheduled to return on Sunday morning, although the skies could clear up by the time race proceedings get underway.
The elements are sure to throw a spanner into the works of some but could contribute to an entertaining 56 laps and another surprising result.
GALLERY: All the Thursday pics from Shanghai
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