The drivers have started their engines and the Pennsylvania 400's green flag is now imminent.
NASCAR has confirmed there will be a competition caution flag at lap 20. Competition yellows are standard procedures in races that have been affected by rain during the morning or at any point since their last practice session.
Rain at Pocono has been a bit of a common theme in the August race. This is the fifth-straight year that rain has plagued the event at some point. In 2007, the last year the August race went dry, the June event was shortened by rain.
With a green race track - that is, a track with all the rubber that had been laid down over the course of the weekend washed off - teams have little to no idea what to expect when the race gets going in terms of handling and tire wear. The competition caution will help, of course, but the opening laps of the race promise to be treacherous.