The climate of the Andamans themselves may be described as normal for tropical islands of similar latitude. It is always warm, but with sea-breezes; very hot when the sun is northing; irregular rainfall, but usually dry during the north-east, and very wet during the south-west monsoon. Not only does the rainfall at one place vary from year to year, but there is an extraordinary difference for places quite close to one another.

The Islands are barely affected by the often disastrous cyclones that come up the Bay of Bengala cyclone, though they are within the influence of practically every one. The Andamans thus were once of great importance for monitoring weather in the region for the benefit of the Indian mainland and ships at sea in the Indian Ocean. A meteorological station was established at Port Blair in 1868.