A tropical storm or hurricane that develops as a tropical storm fairly close (<1000 km / 600 mi) to the Cape Verde Islands in the eastern Atlantic basin may be termed a Cape Verde-type storm or hurricane. These hurricanes have a marked tendency to mover west-northwestward toward the US and Canadian Atlantic Coasts. (Hurricane Ivan, 13 September 2004 shown on the right.)
At times, the term Cape Verde Season is used to distinguish the period during the Atlantic hurricane season when storms are more likely to form off the Cape Verde Islands, generally in August and September. At this time, strong hot air flows across the African Continent and heads west across the Atlantic Ocean, picking up precipitation and energy as it moves toward the South American Continent and the Caribbean/West Indies. Because these storms have miles of warm, open ocean to traverse before encountering the island and mainland of the Americas, they can become the major hurricanes.
The Cape Verde Islands are located in the mid-Atlantic Ocean some 570 km (354 mi) off the west coast of Africa at about 16°N 24°W. Satellite image of the Cape Verde Islands from NASA's Visible Earth and NASA's MODIS Rapid Response Team
Cape Verde hurricanes begin as easterly waves in the tropical easterly atmospheric circulation westward from Africa. These tropical waves arise over the African savanna during the wet season, and then move across the North African deserts on their way toward Africa’s west coast. Some of these waves form tropical depressions and eventually become tropical storms and hurricanes as the trade winds push them across the Atlantic. Most waves, however, just dissipate without forming an organized storm. In an average season, two Cape Verde-type hurricanes form.
General Track of Cape Verde Storms Courtesy NOAA
Cape Verde tropical storms normally gain hurricane strength in the mid-Atlantic Ocean, though some are late bloomers and do not intensify until they reach the Caribbean. A few will reach maturity close to Cape Verde. Because the typical early track of Cape Verde hurricanes avoids both land and cool waters, these tempests generally become long-lived storms. Hurricane Faith remained a tropical storm for 18 days and hurricane (peaking at Category 3) for 10 days in August 1966, and Hurricane Donna (1960) sustained major hurricane status for nine days, hurricane status for 13 days, and was at least a tropical storm for 16 days.
Common Storm Tracks
Once a storm reaches the American side of the Atlantic, several general paths can be identified. If the location of the storm is far enough south and it continues westward, the hurricane will cross the Lesser Antilles into the Caribbean and then track toward southern Mexico, Honduras, Nicaragua, or Belize (e.g., Hurricane Allen in 1980). A slightly more northerly track will travel up the Greater Antilles and head for the US Gulf Coast, or pass through the Bahamas to southern Florida (e.g., Hurricane Geroges in 1998).
Storm Track for Hurricane Allen (1980)
Storm Track for Hurricane Georges (1998)
Created using Wikipedia:WikiProject Tropical cyclones/Tracks. The background image is from NASA with tacking data from the US National Hurricane Center
If the approach is well to the north of the previous track, the hurricane will pass north of the Antilles and begin to curve northward, often making landfall in the Carolinas (e.g., Hurricane Hugo in 1989) or perhaps New England (e.g., Hurricane Eduardo in 1996) if the curve is sharp enough. At other times, these storms curve back out to sea where they die over the colder waters of the mid-Atlantic.
Storm Track for Hurricane Hugo (1989)
Storm Track for Hurricane Edouard (1996)
If the subtropical ridge, often called the Bermuda high, is strong enough, it will cause an approaching storm to curve well before approaching the western Atlantic (e.g., Hurricane Felix in 1989), and these storms burn themselves out in mid-ocean and never effect land as a tropical storm, though they may strike Europe as an extratropical storm.
Storm Track for Hurricane Felix (1989)
Storm Track for Hurricane Andrew (1992)
Some of the most destructive hurricanes to hit the American mainland were known to be Cape Verde tropical storms. Perhaps the two most infamous are The Galveston Hurricane of 1900 and the Great Hurricane of 1938. But, equally destructive Hurricanes Donna (1960), Hugo (1989), Gloria (1985) and Andrew (1992) were also Cape Verde hurricanes.
Storm Track for 1900 Galveston Hurricane
Storm Track for 1938 New England Hurricane
Here is a list of know major Cape Verde Hurricanes. Major hurricanes are hurricanes which have reached the Category 3 on the Saffir-Simpson Hurricane Scale. The hurricane's peak category given in the table is the peak intensity of the hurricane during its lifetime.