Why is the onset of the southwest monsoon associated with sudden rainfall and thunder?

Correct answer: Because moist winds quickly meet dry and hot land

The direct answer is A: moist winds meet the hot, dry land and produce a sudden change in weather. At the beginning of the southwest monsoon, moisture-laden winds arrive over very hot land. Strong heating, rising air, uplift, condensation, and unstable conditions can produce sudden heavy showers, gusty winds, lightning, and thunder. This quick transition is commonly called the “burst of the monsoon.” Option A is the best answer because it connects moist incoming winds with the hot land and the sudden weather change. Option B is wrong because sunlight does not stop; clouds may reduce it temporarily. Option C is wrong because the Himalayas are important for blocking and guiding monsoon winds, but they do not send rainfall back as the direct cause of onset. Option D is wrong because monsoon winds carry moisture rather than losing all of it before rainfall. Memory cue: monsoon burst means sudden rain, wind, and thunder after moist winds arrive.