The Atlantic Hurricane Season comes to a close on Monday. The average number of named storms is 9.6, with 5.3 of them becoming hurricanes. On average, there are 2.3 major hurricanes.
Back in April before the season started, the folks at Colorado State predicted 12 named storms and 6 hurricanes, with two of those hurricanes going on to attain major hurricane (category three or higher) status. With El Nino conditions developing, they downgraded their forecast in early June, predicting 11 named storms, 5 hurricanes and 2 major hurricanes. Through July, there had been no named storms or hurricanes. The team at CSU then downgraded their predicted number of named storms to 10.
How has their forecast panned out over the last four months of the season? We will close the books on a 2009 season that saw 9 named storms, three hurricanes and two major hurricanes.
Tropical Storm Ana formed in mid-August in the Atlantic east of the islands. The system was unable to intensify, thanks to an extremely strong trade wind flow and the system dissipated a couple of days later. Hurricane Bill was a fairly typical Cape Verde hurricane, steering around the periphery of the Bermuda High. It was the strongest hurricane of the year and one of two major hurricanes. Bill attained max intensity of 135 mph/943 mb, making it a category four hurricane. It brushed Newfoundland as it became extratropical. Tropical Storm Claudette formed in t he eastern Gulf of August 16th and became a tropical storm before making landfall near Fort Walton on the 17th with top winds of 50 mph. It was one of two landfalling U.S. tropical storms this year.
Danny was a late August tropical storm that formed east of the Bahamas. It moved northwestward before being absorbed by a frontal system off the Carolina coast. Tropical Storm Erika formed September 1st to the east of the Virgin Islands. It weakened quickly as it moved through the northern Leeward Islands on the 2nd and dissipated over the northeastern Caribbean. Hurricane Fred was the second strongest and second major hurricane of the year, but it remained over the far eastern Atlantic. Tropical Storm Grace formed from a frontal system over the far northeastern Atlantic, northeast of the Azores in early October.
Henri was an early October tropical storm that formed east of the Leewards. The system weakened before it reached any land areas. Ida formed over the western Caribbean in early November. It made landfall in Nicaragua and dumped heavy rains on that country and Honduras before moving back over the warm water and becoming a hurricane. It moved into the Gulf and made landfall near Dauphin Island as a weak tropical storm on November 10th. It was the second latest U.S. landfalling tropical storm or hurricane on record..
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