Storm season has been quiet so far, but weather models show the Saharan air clearing and the shear slowing as we enter the busy season. 'It’s definitely going to get more active. I’ll hang my hat on that,’ expert says.
Hurricane experts are watching an atmospheric shift in the tropics that could trigger activity next week as the slowest season since 1999 hits its peak.
With Subtropical Storm Andrea struggling to life in May, just one named storm - Hurricane Barry - has formed since the official start of hurricane season. That lack of tropical cyclones between June 1 and mid-August hasn’t happened in two decades, according to Colorado State University researcher Phil Klotzbach.
Stifled by an Atlantic basin choked with Saharan dust and a ripping wind shear, there hasn’t been a tropical wrinkle worth noting since Aug. 4 when a wave fizzled 200 miles east of the Lesser Antilles.
But weather models show the Saharan air clearing and the shear slowing, opening a window of opportunity if an ambitious disturbance wants to become something more.
“We’re about due to see some action coming our way,” said Dan Kottlowski, senior hurricane forecaster at AccuWeather. “I call it atmospheric opportunism, when weather features try to take advantage of the situation.”
Jeff Masters, co-founder of Weather Underground, notes that a forecast from the National Oceanic and Atmospheric Administration is calling for wind shear to calm to “near-average” levels from late August through late September.
“If this forecast verifies, it will mean favorable conditions for Atlantic hurricanes during the most dangerous part of the season,” Masters said in a column this week.
Still, the atmosphere needs a system willing to test the waters. Two areas of potential development are being watched, Kottlowski said. One is a tropical wave still making its way off the coast of Africa. The other, a large area of showers and thunderstorms occurring across Panama and Costa Rica that could trigger an area of low pressure to form over the Bay of Campeche
“None of this is a given,” Kottlowski said. “There are still atmospheric booby traps in place.”
That includes sea surface temperatures just slightly warmer than normal and how long a windshear hangover lasts after El Nino’s surprise death announced last week.
El Nino, the hurricane-thwarting climate pattern, was expected to last into fall.
NOAA’s lead hurricane forecaster Gerry Bell reiterated the abrupt end of El Nino Thursday during a conference call with 150 meteorologists, emergency managers and reporters from around the country. The demise led Bell to change his earlier forecast for a near-average storm season to one with a 45 percent chance of above-normal activity and a 35 percent chance of near-normal activity.
Bell said when he made his early prediction for the 2019 hurricane season the forecast for El Nino was the “exact opposite” of what has happened.
“It’s definitely going to get more active. I’ll hang my hat on that,” Bell said. “Some years, all of a sudden, you can see the lights turn on in mid-August and everything revs up.”
Eight storms came to life last year between Aug. 15 and Sept. 23, including Florence, which at its strongest was a Category 4 hurricane. Florence made landfall as a Cat 1 near Wrightsville Beach, N.C. on Sept. 14.
In the hyperactive year of 2017, five named storms had formed before Aug. 1, with the peak season of mid-August through September spawning eight more. The season ended with 17 named storms, including 10 hurricanes and six major hurricanes.
“That’s my biggest worry right now, multiple storms going at the same time,” said Kottlowski. “When you look at long-range climate models, it’s looking promising for development.”