90 minutes before Saturday morning practice, plumes of spray are pouring from the rear of the local F3 cars at Interlagos.
Weather forecasts of a very wet day have so far proved correct, with the skies dark and grey and more heavy showers predicted in the gap between F1 practice and qualifying at 2pm.
"Qualifying could be a lottery," former driver and BBC commentator David Coulthard wrote in his Telegraph column.
"When the rain starts falling here, and the rivers start running on the hilly track, predictions go out of the window. Timing your qualifying run is everything," said the Scot.
Sunday’s forecast is for a dry Brazilian grand prix.