2009 hurricane season ends quietly with fewest storms since 1997

Hurricane Bill was the most powerful hurricane of the
2009 Atlantic hurricane season.  See images and
tracks of all nine of the named storms of the season in
our slideshow below. (NASA)

Yesterday marked the end of the 2009 hurricane season and with it comes to a close one of the quietest seasons in recent history. The season featured nine named storms, the fewest since 1997, and for the first time since 2006 no hurricanes made landfall in the United States.

Only two named the storms – Tropical Storm Claudette and Tropical Storm Ida – made landfall in the nation. Those two storms both struck along the central Gulf Coast and brought heavy rain and some flooding but no widespread destruction.

• In pictures - The 2009 Atlantic hurricane season

Of the nine named storms, three became hurricanes. Two of those became major hurricanes of Category 3 strength of higher – Hurricane Bill and Hurricane Fred. Bill flirted with the United States East Coast as its waves claimed two lives but turned to the northeast and made landfall in Newfoundland after having weakened considerably. Hurricane Fred rapidly intensified off the west coast of Africa but quickly fell victim to wind shear.

On the average, the Atlantic hurricane basin has 9.6 named storms, 5.9 of which become hurricanes and 2.3 become major hurricanes. The number of named storms in 2009 fell below initial predictions from Colorado State University but within the forecast range from the National Hurricane Center that was issued in May. Both groups’ initial forecasts were low on the total number of hurricanes but later forecasts were within the range each predicted.

Across the globe, tropical cyclone activity for the calendar is well below the 30 year average. According to Ryan Maue of Florida State University, every basin is experiencing below average activity although the western Pacific is approaching the average thanks to Typhoon Nida.

The ACE index is the standard for measuring tropical cyclone activity. It combines the frequency, duration and intensity of the storms into a numerical index that can be used for historical comparisons.

Maue says that for the Atlantic basin, “2009 was the quietest year since 1997 (ACE= 41) and the 16th slowest since 1940. Interestingly, 2009 saw 1/5th of the activity of 2005, the most active ACE season on record. 3 storms out of the total of 9 accounted for 85% of the total ACE (Bill, Fred, and Ida).”

In a statement, the National Oceanic and Atmospheric Administration said that El Niño played a role in the slow season. “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.”