NOAA Now Expects an Above-Normal Atlantic Hurricane Season

Southern Ocean County — National Oceanic and Atmospheric Administration Climate Prediction Center forecasters are telling the public not to be fooled by the slow start to the 2019 Atlantic Basin hurricane season, which officially kicked off on June 1.

Indeed, they’re upping their forecast, now calling for an above-average season.

That’s rather surprising considering the season has been remarkably quiet as September approaches, the second-slowest start in the 21st century, behind only 2014. There have been just four named storms, including one weak hurricane, as of Sunday.

The first, Andrea, actually formed before the season officially began, way back on May 20 and 21. It turned out to be a subtropical storm, with its highest winds reaching only 40 mph.

Hurricane Barry’s lifespan was from July 11 to July 15. Its peak winds were 75 mph, just breaking the Cat 1 threshold of 74 mph when it made landfall on Intracoastal City, La., on July 13. It caused damage estimated at more than $600 million as it moved inland as a tropical storm, but was blamed for just one death when a man was killed by a rip current off the coast of the Florida Panhandle on July 15.

Tropical Storm Chantel, Aug. 21 to 24, had peak winds of 40 mph. It was only classified as a tropical storm when it was far out to sea, 515 miles south-southeast of Cape Race, Newfoundland.

As of Monday morning Tropical Storm Dorian was located about 225 miles ESE of Barbados and had maximum sustained winds of 60 mph. A Tropical Storm Watch had been issued for Barbados, St. Lucia and St. Vincent, and the Grenadines and was in effect for the Dominica, Martinique and Grenada. It was expected to reach hurricane strength on Tuesday or Wednesday. NOAA said Puerto Rico, the Virgin Islands and Hispaniola should monitor the storm’s progress and also said it was too early to speculate if Dorian will impact Florida.

Back in May NOAA had called for a near-normal Atlantic hurricane season, saying there was a 40 percent chance of a near-normal year while adding there was a 30 percent chance of both a below- and above-normal season. NOAA defines a “normal” season as a dozen named storms and six hurricanes, three of which reach the Cat 3 level, and its May forecast squarely fit in those parameters, calling for nine to 15 named storms and four to eight hurricanes, two to four of which would be of the major variety, Category 3 or above.

The NOAA forecast also fit nicely with an April forecast released by the Colorado State University Tropical Meteorology team that predicted 13 named storms and five hurricanes, two of which would breach the Cat 3 level.

The main reason NOAA and CSU had issued moderate forecasts in the spring was El Niño, warmer-than-normal sea surface temperatures in the central and eastern Pacific Ocean which favor stronger hurricane activity in the central and eastern Pacific basins but suppress it in the Atlantic basin.

“A weak El Niño has recently developed in the tropical Pacific,” read an April 4 CSU press release. “CSU anticipates that these weak El Niño conditions are likely to persist through the peak of the Atlantic hurricane season (August through October). El Niño tends to increase upper-level westerly winds across the Caribbean into the tropical Atlantic, tearing apart hurricanes as they try to form.”

“The ongoing El Niño is expected to persist and suppress the intensity of the hurricane season,” said NOAA in May.

Unfortunately, El Niño didn’t persist.

“NOAA forecasters monitoring oceanic and atmospheric patterns say conditions are now more favorable for above-normal hurricane activity since El Niño has now ended,” read a NOAA statement issued on Aug. 8.

NOAA increased the likelihood of an above-average season to 45 percent, up 15 percent from its May forecast, and dropped its chances of a near-average season to 35 percent and its chances of a below-normal season to 20 percent. It is now calling for 10 to 17 named storms, five to nine hurricanes and two to four major blows.

On Aug. 5 CSU had also increased its forecast, if only slightly. It called for 14 named storms, up one from April, and seven hurricanes, up two from April, although it stuck with its April call for two major hurricanes.

Remember that the 2019 season has started off very slowly, behind only 2014. It turned out that 2014 ended up as a below-average season, with just eight named storms, six of which became hurricanes, of which only two reached the Category 3 level.

Still, also remember August through October is the peak of the Atlantic basin hurricane season. Hurricane/Superstorm Sandy, for example, made landfall in New Jersey on Oct. 29, 2012.

— Rick Mellerup

Reposted from The Sandpaper