Tropical Storm
Tropical Storm, weather system composed of a cluster of thunderstorms and of wind speeds near the surface of between 63 and 119 km/h (39 and 74 mph). Tropical storms develop out of storms called tropical depressions, in which wind speeds are less than 63 km/h (39 mph). If a tropical storm intensifies so that its wind speed reaches 119 km/h (74 mph), the storm becomes a hurricane. In contrast to a hurricane, a tropical storm typically does not have an eye, or calm area, at its center. Tropical storms form over large expanses of warm tropical ocean water. However, they do not form in the regions of the eastern Pacific or the Atlantic oceans near the equator or south of the equator. Tropical storms cause torrential rainfall and flooding, which pose the gravest threat to populated areas. For example, in 1994, tropical storms Alberto, Beryl, and Gordon caused nearly $1 billion worth of damage in the United States. The flooding caused by Alberto killed 30 people in Alabama and Georgia. In Ju...