[TigersEye]

rain

noun

1. water that is condensed from the aqueous vapor in the atmosphere
and falls to earth in drops more than 1/50 inch (0.5 mm) in diameter.
Compare drizzle (def 6).

2. a rainfall, rainstorm, or shower:
We had a light rain this afternoon.

3. rains, the rainy season; seasonal rainfall, as in India.

4. weather marked by steady or frequent rainfall:
We had rain most of last summer.

5. a heavy and continuous descent or inflicting of anything:
a rain of blows; a rain of vituperation.

[Ray76]

As I said. The operative word is “season”