Atmospheric Currents as Observed in the West Indies, and Particularly in St. Thomas

Abstract

DURING an average period of nine months in the year the regularity of the air-currents over the Virgin group resembles clockwork. The surface, or lowest current is formed by the trade-wind, which blows briskly from the north-north-east, with a slight variation north-ward during the night and early morning, and a corresponding deflection southward from noon till near sunset. Varying in strength from a light breeze to a brisk gale, it is hardly ever absent; its greatest strength is usually at or near 3–4 A.M., and about the same hours P.M. It generally bears with it light masses of cumulus, from which there fall occasionally showers, heavy, but very short in duration. This air-current, known as the trade-wind of these regions, does not appear to exceed 2,000 feet in vertical height.