The islands rely heavily on regular weather advisories issued by NWS and these are broadcast several times daily on local radio stations. The seeds of a potential Hurricane originate in the warm tropical waters of the Atlantic off the west coast of Africa. Throughout the Hurricane season a series of wet weather systems forms in this area and steadily drifts westward carried by the constant trade winds. These alternate with periods of fair weather at intervals of about 4 to 5 days. As it moves westward the system may intensify as it gradually accumulates energy from the warm ocean waters.
Meteorologists define several stages in the evolution of a storm system.
Tropical Wave - This is the name given to the normally occuring cycle of clouds and showers which can be expected about every 5 days. Tropical Disturbance - This category indicates that the system has begun to rotate slightly but there is no evidence of strong winds. This will occur quite often and although not a cause for concern meteorologists will be watching for any further strengthening. Tropical Depression - With this classification the system is exhibiting a more organised degree of rotation and winds have increased up to 34 knots or 39 m.p.h. Tropical Storm - The system has now developed significantly in intensity with steady winds of up to 63 knots or 73 m.p.h.