Explanation:

The correct word to fill the blank is 'weather'. 'Weather' refers to the state of the atmosphere at a particular place and time, regarding heat, dryness, sunshine, wind, rain, etc. After rain, the immediate atmospheric conditions often improve. Option (1) 'season' refers to a long period of the year, not changed by a single rain. Option (2) 'climate' is long-term average weather, not affected by one event. Option (3) 'whether' is a conjunction, grammatically incorrect here.