WSI Issues 2009 Hurricane Season Update

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Weather Authority's Tropical Forecast Calls for Less Active Season than Last Year

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Ocean temperatures in the tropical Atlantic are cooler, relative to normal, than at any time since 1994

WSI Corporation's updated 2009 hurricane season forecast now calls for 11 named storms, 6 hurricanes, and 2 intense hurricanes (category 3 or greater).

These forecast numbers are lower than those from the WSI forecast issued in December (13 named storms, 7 hurricanes, and 3 intense hurricanes) due to a continuation of relatively cool tropical Atlantic Ocean temperatures and a waning of the recent La Nina event. The 2009 forecast numbers are quite close to the long-term (1950-2008) average of 9.8 named storms, 6.0 hurricanes, and 2.5 intense hurricanes).

The 2009 WSI tropical forecast comes on the heels of a very successful 2008 forecast. The WSI December forecast values of 14 named storms, 7 hurricanes, and 3 intense hurricanes were slightly smaller than the final observed 2008 values of 16/8/5. The subsequent updates improved the forecast further, as the April 2008 updated forecast values of 14 named storms, 8 hurricanes, and 4 intense hurricanes were the most accurate amongst the publicly-available forecasts issued last spring.

"Ocean temperatures in the tropical Atlantic are cooler, relative to normal, than at any time since 1994," said WSI seasonal forecaster Dr. Todd Crawford. "Further, the recent La Nina event has now ended, and we expect normal or even slightly above-normal wind shear in the tropical Atlantic this season. Neither the cooler tropical Atlantic nor the neutral wind shear conditions are enabling for tropical activity this year. We have reduced our forecast numbers to adapt to the latest information, and future changes to our forecast are more likely to be towards smaller numbers than larger numbers."

Energy and agricultural traders, insurance professionals and risk managers look to WSI for accurate, timely weather information around the clock and across the globe. The next full seasonal forecast package, which will include forecasts for summer temperatures in both the US and Europe, will be issued on May 27. The next update on the 2009 hurricane season will be issued on May 26.

About WSI
WSI Corporation is the world's leading provider of weather-driven business solutions for professionals in the energy, aviation, and media markets, and multiple federal and state government agencies. WSI is headquartered in Andover, Massachusetts with offices in Birmingham, England and was recently purchased by a consortium made up of NBC Universal and the private equity firms The Blackstone Group and Bain Capital. More information about WSI can be found at


Kristen Sullivan
WSI Corporation
(978) 983-6607

Editorial Contact:
Barbara Rudolph    
Rudolph Communications, LLC
(781) 229-1811

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