‘Marshals unable to work due to the proximity of lightning’ was the message from race control just prior to the scheduled start of the 90-minute session at 1400 hours local time, and unfortunately conditions never improved enough for the required medical helicopter to fly.
It means the teams end day one in the United States with no dry running under their belts. Opening practice - topped by Mercedes’ Nico Rosberg - had been staged on a damp track with the drivers primarily using Pirelli’s intermediate tyres. Just 206 laps were completed - an average of just over 10 per car.
Forecasts suggest that the poor weather is expected to continue into Saturday.