The 2009 Atlantic hurricane season officially ends today marking the close of a season with the fewest named storms and hurricanes since 1997 thanks, in part, to El Niño.
Nine named storms formed this year, including three hurricanes, two of which were major hurricanes at Category 3 strength or higher. These numbers fall within the ranges predicted in NOAA’s mid-season outlook issued in August, which called for seven to 11 named storms, three to six hurricanes, and one to two major hurricanes. An average season has 11 named storms and six hurricanes, including two major hurricanes.
“The reduced activity was expected and reflects the development of El Niño during the summer,” said Gerry Bell, Ph.D., lead seasonal hurricane forecaster at NOAA’s Climate Prediction Center, a division of the National Weather Service. “El Niño produced strong wind shear across the Caribbean Sea and western tropical Atlantic, which resulted in fewer and shorter-lived storms compared to some recent very active seasons.”
Two systems, Claudette and Ida, brought tropical storm force winds to the U.S. mainland. For the first time in three years, no hurricanes hit the U.S. There were 38 hurricane hunter aircraft reconnaissance missions flown by NOAA and the U.S. Air Force over the Atlantic Basin this year compared to 169 in 2008 – another indication of a less active season.
“El Niño is expected to reach peak strength this winter, and will likely continue into the spring. It is far too early to say whether El Niño will be present next summer,” added Bell. NOAA will issue its initial 2010 Atlantic Hurricane Outlook in May, prior to the official start of the season on June 1.