Bermuda’s climate is warm-temperate or sub-tropical. It is free of frost and snow despite its latitude of 32 degrees north, which is the same as Charleston, South Carolina. The relatively mild climate is attributable to warm waters of the Gulf Stream, which flows northwards on the eastern side of Bermuda. The oceanic conditions, around Bermuda, are responsible for high humidities and moderated temperatures. The minimum monthly average day-time temperatures of 680 F or 200 C occurs in February; while the maximum of 860 F or 300 C occurs in August.
A high pressure system known as the Bermuda-Azores High builds and is strengthened in the Summer by the presence of the Gulf Stream. It extends to the west of Bermuda and deflects, or weakens, frontal systems, which in the Winter arrive at Bermuda from the north west bringing cold and stormy weather.
Rainfall is evenly distributed throughout the year with an annual average of 57.4″ or 1458 mm, (see below). It tends to be delivered by frontal systems in the winter and by tropical disturbances and local thunderstorms in the summer. Extended wet periods are usually caused by fronts lying almost stationary over Bermuda.
Rainfall chart compiled from Macky 1852 – 1956; Bermuda Government 1956 – 1990; Bermuda Weather Service 1990 – 2006. Main locations: Fort George, Prospect, Botanical Gardens and Airport.