Hurricane season may rank among the busiest on record, NOAA says

One indicator that the hurricane outlook issued by NOAA on Thursday was on the frightful side of scary was a plea for perspective from the director of the National Weather Service.

“Let’s keep everyone calm out there,” weather service chief Ken Graham said at a teleconference at which NOAA called for 17 to 25 named storms — those with winds of at least 39 mph — “the greatest number that we’ve forecast” in 25 years of issuing outlooks.

With record-warm ocean temperatures persisting, the Atlantic hurricane season that begins officially June 1 could well become one of the most active in the period of record, NOAA warned.

NOAA said it expects eight to 13 of the storms to become hurricanes, with winds of 74 mph or more, and four to seven of those growing into “major” status, with winds of 111 mph or higher.

Normally, the season produces 14 named storms, seven hurricanes, and three major hurricanes. The record for named storms is 30, set in 2020.

The NOAA forecast is strikingly similar to those released earlier by other major services, and that’s not surprising, given the antecedent conditions.

The atmosphere from the tropical Pacific to the west coast of Africa is primed to incite tropical storms in the Atlantic Basin — which includes the Gulf of Mexico and the Caribbean Sea — said Matt Rosencrans, hurricane researcher with the government’s Climate Prediction Center.

The vast El Niño warming of the tropical Pacific, a reliable source of west-to-east winds that interfere with storm development in the Atlantic, is yielding to a widespread cooling, or La Niña.

Graham said he has seen incipient storms encounter warm water, only to get ripped apart by shearing winds. With La Niña, shear is going to be less of a factor this season.

Monsoon activity in western Africa can generate disturbances that can “seed some of the strongest and longer-lived Atlantic storms.”

Those are the kind that form off the African coast and ponderously ply the waters, sending waves of fright along the East Coast and the Caribbean islands.

The elephant in the Atlantic outlooks is the warmth of the water, forecasters agree. Oceanic heat is a lifeblood of hurricanes.

Rosencrans estimated that sea-surface temperatures out that way are about 3 degrees Fahrenheit above normal. Oceanic heat is a hurricane lifeblood.

The readings are already about where they should be on Aug. 12, said Philip Klotzbach, hurricane researcher at Colorado State University.

Along with increasing global warmth, researchers say the waters are getting an extra toasting as a result of a positive development — less pollution. “The air is cleaner,” said John Gyakum, an atmospheric researcher at McGill University in Montreal who specializes in climate change-related extreme weather. “That makes definitely for less reflection and warmer temperatures.”

Just how much the reduction in aerosols is contributing to the warming remains a research question, Rosencrans said. What isn’t in question is the present state of the waters.

“They are dramatically warmer” than they were in the ultra-busy seasons of 2005, the year of Katrina, and 2020.

An abnormally active season isn’t a done deal, Rosencrans said.

But it’s close.

“We did put a 5% chance of below” normal activity, he said. “There’s always a small chance there’s something we missed. We can’t measure every cubic millimeter of the planet all the time.”

If NOAA did miss something, it will have plenty of company.

Here are what the other forecasters are saying: