There’s a high likelihood of below-normal tropical cyclone activity in the Atlantic basin this year, the U.S. National Oceanic and Atmospheric Administration’s Climate Prediction Center stated in its annual pre-season forecast issued on Wednesday.
The Atlantic basin hurricane season starts on June 1 and runs through Nov. 30.
For 2015, NOAA predicts a 70 percent likelihood of a below-normal hurricane season with six to 11 named storms, three to six of which will become hurricanes, and zero to two will become major hurricanes.
It predicted a 20 percent chance of a “near-normal” hurricane season and a 10 percent chance of an above-normal season. A “normal” Atlantic basin hurricane season sees 11 named storms, six hurricanes and two major hurricanes.
NOAA Administrator Kathryn Sullivan said the below-normal season prediction does not mean anyone in the basin was off the hook.
“As we’ve seen before, below-normal seasons can still produce catastrophic impacts to communities,” she said, referring to the 1992 season in which only seven named storms formed, but the first was Andrew, a Category 5 major hurricane that devastated areas of South Florida.
The main reason for predicting the lower-than-normal amount of tropical cyclone activity is the formation of a strong El Niño, an anomalous warming of the waters of the tropical Eastern Pacific Ocean that creates in the Atlantic basin higher wind shear, which hinders the formation and strengthening of tropical systems.
The Climate Prediction Center’s lead seasonal hurricane forecaster, Gerry Bell, said El Niño, which is already affecting wind and pressure patterns, is forecast to last through the hurricane season.
“El Niño may also intensify as the season progresses and is expected to have its greatest influence during the peak months of the season,” he said. “We also expect sea surface temperatures in the tropical Atlantic to be close to normal, whereas warmer waters would have supported storm development.”
Despite the prediction of a below-normal amount of tropical cyclone activity this year, NOAA urged people to prepare as they do every year.
“It only takes one hurricane or tropical storm making landfall in your community to significantly disrupt your life,” said FEMA Deputy Administrator Joseph Nimmich. “Everyone should take action now to prepare themselves and their families for hurricanes and powerful storms. Develop a family communications plan, build an emergency supply kit for your home, and take time to learn evacuation routes for your area. Knowing what to do ahead of time can literally save your life and help you bounce back stronger and faster should disaster strike in your area.”
Colorado State University’s Phil Klotzbach and William Gray, who also make annual hurricane season predictions, will issue their beginning-of-the-season forecast on Monday. Their pre-season forecast issued in early April also predicted a below-normal season.
“We anticipate that the 2015 Atlantic basin hurricane season will be one of the least active seasons since the middle of the 20th century,” they said in their forecast report, also pointing to El Niño as the main cause.