| MadSci Network: Earth Sciences |
There are two situations where rain occurs. The first is the passage of a cold front or sometimes (but not usually) a warm front. This can happen any time of the day or night, so there's a 50-50 chance of rain happening in the daytime or at night. The other situation is typical summer thunderwhower weather, where rain comes about as the result of surface heating of the Earth. This occurs almost exclusively in the daytime, though showers produced this way can linger into the evening. Net result - it rains more often in the daytime. Thanks for asking.
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