Hurricane Season 2015
Below-normal Atlantic hurricane season ends; active eastern and central Pacific seasons shatter records
December 1, 2015
The 2015 Atlantic hurricane season ended with a below-normal 11 named storms, four of which became hurricanes. (Credit: NOAA)
The Atlantic, eastern and central Pacific hurricane seasons officially ended yesterday, and as predicted, the Atlantic season stayed below normal with 11 named storms, while the eastern and central Pacific were above normal with both regions shattering all-time records.
Overall, the Atlantic hurricane season produced 11 named storms, including four hurricanes (Danny, Fred, Joaquin and Kate), two of which, Danny and Joaquin, became major hurricanes. Although no hurricanes made landfall in the United States this year, two tropical storms – Ana and Bill – struck the northeastern coast of South Carolina and Texas, respectively. Ana caused minor wind damage, beach erosion and one direct death in North Carolina, and Bill produced heavy rain and flooding while it moved across eastern Texas and Oklahoma. Hurricane Joaquin is the first Category 4 hurricane since 1866 to impact the Bahamas during the month of October.
NOAA scientists credit El Niño as the leading climate factor influencing both the Atlantic and Pacific seasons this year.
“El Niño produces a see-saw effect, suppressing the Atlantic season while strengthening the eastern and central Pacific hurricane seasons,” said Gerry Bell, Ph.D., lead seasonal hurricane forecaster at NOAA’s Climate Prediction Center. “El Niño intensified into a strong event during the summer and significantly impacted all three hurricanes seasons during their peak months.”
Bell said El Niño suppressed the Atlantic season by producing strong vertical wind shear combined with increased atmospheric stability, stronger sinking motion and drier air across the tropical Atlantic, all of which make it difficult for tropical storms and hurricanes to form and strengthen. However, El Niño fueled the eastern and central Pacific seasons this year with the weakest vertical wind shear on record.