If the weather takes a turn for the worse in an Ohio State game, you can bet the quarterback is going to run the ball quite a bit.
Urban Meyer won games that way at Bowling Green with Josh Harris. He did it at Utah with Alex Smith, Florida with Tim Tebow and at Ohio State first with Braxton Miller and now with J.T. Barrett. The quarterback run is a weapon in his eyes; it creates an advantage for the offense provided his tailback and receivers can block.
But Meyer shortens the playbook exponentially when the weather is not cooperative or he has little to no confidence in Barrett throwing the ball.