The night Andy, the star of The Shawshank Redemption, ran away, he was sure it would rain and thunder. Andy's escape is not a sudden passion escape, but after long-term planning and preparation, he needs thunder as a cover to crush the sewage pipe. If it hadn't thundered, Andy's noise of smashing sewage pipes would have spread all over Shawshank prison, so he had to calculate when it would thunder and rain to finish his escape.

Andy knows common sense very well. He knows that the speed of light is faster than the speed of sound, and it usually thunders three seconds after lightning appears. So when he smashed the sewage pipe, Andy looked at it and prepared to smash the sewage pipe. After seeing the lightning, he will wait for three seconds before smashing the sewage pipe. He knows common sense, so he naturally knows how to observe the clouds, feel the humidity of the air, and observe the living habits of insects on the surface. He can be sure which day it will rain.

Andy is a financier, and his love for geology has always been the protagonist. It is precisely because people who study geology usually know how to identify the weather that he has been pushing the library not only for prisoners, but also to expose themselves to more books on weather judgment.

Besides, Andy works in the warden's office every day. The warden's office is fully equipped. Andy can listen to the weather forecast in the warden's office and get the latest weather information, so it is not difficult for him to calculate the time of thunder and rain.

In fact, Andy had already made all the preparations, just waiting for a night of thunder, but the film didn't shoot him waiting for a chance to move, and he didn't clearly film his efforts in this regard, so it seemed like an epiphany.