Vientiane features a tropical savanna climate (Köppen ''Aw'') with a distinct wet season and a dry season. Vientiane's dry season spans from November through March. April marks the onset of the wet season which in Vientiane lasts about seven months. Vientiane tends to be very hot and humid throughout the course of the year, though temperatures in the city tend to be somewhat cooler during the dry season than the wet season.