Lingering La Niña Weather Phenomenon Boosts Threat of More Atlantic Hurricanes

The odds of La Niña hanging around for a few more months are climbing, bolstering chances of more storms as the Atlantic hurricane season reaches its peak.

There’s an 80% chance the waters across the equatorial Pacific Ocean will stay cool through October, according to the U.S. Climate Prediction Center’s latest data. That’s higher than the 62% odds the agency forecast in July.

The weather phenomenon known as La Niña happens when the Pacific cools enough to upset weather patterns above its surface. Such changes can cause less wind shear across the Atlantic, which allows tropical storms and hurricanes to grow stronger.

The agency also sees a 72% chance of La Niña between November and January, up from 65% in the prior forecast. Winds across the equatorial Pacific are helping cooler subsurface waters rise to the top, said Michelle L’Heureux, a forecaster with the Climate Prediction Center. That’s likely to prolong the phenomenon.

“We’re already in a La Niña,” she said in an interview. “This is kind of recharging the entire process.”

If the weather-roiling event does make it into the Northern Hemisphere’s winter, it would be only the third time the phenomenon has happened three years in a row since 1950.

Atlantic hurricanes pose significant risk to orange juice production in Florida and natural gas and oil extraction and refining in the Gulf Coast region. The U.S. National Oceanic and Atmospheric Administration said earlier this month that it expects 14 to 20 named storms this season, down from its May estimate of as many as 21.