There's a 50 percent chance of storms from 3 p.m. to 6 p.m. ET on Sunday, according to WTAE in Pittsburgh, and radar predictions indicate that the heaviest rain will fall around 4 p.m. The showers will likely be spotty, though, with intermittent sunshine between.

Today's forecast calls for about a 50% chance rain throughout the morning, according to AccuWeather, with a slight break about the time the final pairings are scheduled to tee off in the afternoon. But that gives way to a 60% chance of rain starting about 5 p.m. through close to sunset.