Increase in temperature after an unexpected rain during summer Why we feel an increase in temperature of atmosphere than usual after an unexpected rain during summer? Usually the raining should have to reduce the temperature of atmosphere.
 A: If rain falls through air that isn't already saturated with water vapor, some of that rain will evaporate, cooling both the rain and the air, just as you say.
However, more humid air may not feel cooler, because part of the sensation of air temperature is evaporative cooling from your skin. The more humid the air, the less it will support evaporation, and the less cooling you'll feel.
But rain frequently comes because of moving air masses. If you notice that it's warmer after a rain, it's likely because warmer air has moved in behind the storm.
Edit to add: this question is probably more appropriate for Earth Science...?
A: One should add to the other arguments that in general water precipitation in closed systems releases heat into the environment. Going from gas to liquid, energy is released in the form of infrared photons, for the molecules that bind into drops. It is the opposite of evaporation, which cools surfaces due to the energy taken away.
How much this affects the rain drops and the ambient temperature will depend on how the droplets form, if very high up the effect will be small. If the humidity is very high and the drops form close to the ground it will be detectable. ( after all evaporation cooling is detectable once a wind blows)
