Seattle's track (Pacific Raceways) is notorious for this. Keep in mind rain in Seattle is not exactly rare.
When it starts raining, they close down the track, obviously. They then tell you the foracast over the loudspeakers. Over and over, while saying they are waiting to get restarted. This can go on for hours. The sky could be black but they will wait until about 3/4 of the field has left before calling the event and issuing return passes.
The passes do get car and driver back in though.