Moist air holds heat better than dry air.

Yea, I can see this. I live in Oklahoma, and the more humidity the hotter it seems. It's like we have 90 degree weather but it feels like 99 because of the 100% humidity.

wath

must be why the tempeture is sometimes hotter when it rains than other days

It's due to the enthalpy of water. Water takes the most amount of energy to warm or cool. If the air is humid (high water content), then the air will not cool easily. Like a hot tub in the winter...