The raindrops are falling faster and faster; a heavy rain is about to arrive.
Tips
usage
雨点 refers to individual drops of rain. Compare with 雨水 (yǔshuǐ, rainwater) which refers to rain as a substance, and 雨 (yǔ) which refers to rain in general. The idiom 雷声大,雨点小 (loud thunder, tiny raindrops) means all talk and no action.