NOAA’s Climate Prediction Center is forecasting a near-normal or below-normal season for Atlantic hurricanes.
The main driver of this year’s outlook is the anticipated development of El Niño this summer. El Niño causes stronger wind shear, which reduces the number and intensity of tropical storms and hurricanes. El Niño can also strengthen the trade winds and increase atmospheric stability across the tropical Atlantic, making it more difficult for cloud systems coming off of Africa to intensify into tropical storms.
The outlook calls for a 50 percent chance of a below-normal season, a 40 percent chance of a near-normal season, and only a 10 percent chance of an above-normal season. For the six-month hurricane season, which begins June 1, NOAA predicts a 70 percent likelihood of eight to 13 named storms (winds of 39 mph or higher), of which three to six could become hurricanes (winds of 74 mph or higher), including one to two major hurricanes (Category 3, 4 or 5; winds of 111 mph or higher).
These numbers are near or below the seasonal average of 12 named storms, six hurricanes and three major hurricanes, based on the average from 1981 to 2010. The Atlantic hurricane region includes the North Atlantic Ocean, Caribbean Sea and Gulf of Mexico.
Gerry Bell, Ph.D., lead seasonal hurricane forecaster with NOAA’s Climate Prediction Center, said the Atlantic — which has seen above-normal seasons in 12 of the last 20 years — has been in an era of high activity for hurricanes since 1995. However, this high-activity pattern is expected to be offset in 2014 by the impacts of El Niño and by cooler Atlantic Ocean temperatures than we have seen in recent years.
“Atmospheric and oceanic conditions across the tropical Pacific are already taking on some El Niño characteristics,” Bell said. “Also, we are currently seeing strong trade winds and wind shear over the tropical Atlantic, and NOAA’s climate models predict these conditions will persist, in part because of El Niño. The expectation of near-average Atlantic Ocean temperatures this season, rather than the above-average temperatures seen since 1995, also suggests fewer Atlantic hurricanes.”