Throughout much of the country there are two rainy seasons. The masika (long
rains) fall from mid-March through to May, with rains virtually every day,
although seldom for the whole day.
The mvuli (short rains) fall during November, December and sometimes into January.
Concerning humidity is Mwanza also a very friendly town. Because of the relatively high location above sea level (1.134 m) is the humidity normal (medium dry) and vary from 50 - 65% throughout the year.
Today's Mwanza weather - and 5 day forecast from Yahoo.com