Average monthly rainfall in the wet season never drops below 200 mm. It is highest in May and lowest in June. Humidity routinely registers about 80% during the wet season. The chart below shows the average rainfall in mm by month. Statistics are courtesy of the Maldives Meteorological Service for calendar year 2010.uring the dry season, the average monthly rainfall, expressed in millimeters (mm), is highest in November and lowest in February. Being close to the equator and surrounded by water, humidity is always pretty high. A 75% rate of humidity is not uncommon during parts of the dry season.