Great news for those that live on the coasts, bad news for the FEMA and relief truckers- hurricane season activity will be almost not existant this year. Pretty much all key predictive variables, from sea surface temperatures to wind shear, suggest the current hurricane season will not hold a candle to last year’s hyperactive season in the Atlantic Basin, according to Riskpulse’s hurricane season mid-August update.
“At this time last year, Harvey was beginning to make its way across the Atlantic. That marked the beginning of the hyperactive period that started in August and lasted into October,” Riskpulse Chief Meteorologist Jon Davis said. “This year, the overall region of the Tropical Atlantic is in a fundamentally different stage than it was in a year ago.”
The Pacific Ocean has seen a much more active season so far, with Hurricane Hector passing south of Hawaii earlier this month and Tropical Storm Lane expected to intensify into a hurricane and make its way south of the Big Island sometime next week.
“A very active Pacific is one of the themes we’ve had this year, and much of the time we see a correlation: when the Pacific is very active, the Atlantic Basin is not,” Davis said.
Ernesto, the fifth named Atlantic storm of the season, is moving toward the United Kingdom and not expected to affect land. It is the latest in a line of relatively weak storms. A tropical wave that came off of Africa about a week ago is moving toward the Caribbean, but unfavorable conditions are expected to stop any storm development in its tracks, according to Davis.
“Another thing that we see in the image is a lot of dust that is coming off of Africa. That is a tropical storm or hurricane killer,” he said. “When we see this, even though we have tropical waves, it tends to make it difficult for those storms to gain intensity as they move across the Atlantic.”
Sea surface temperatures in the main development region of the Atlantic are also colder than normal, while temperatures in the Pacific are warmer and shifting toward an El Niño. These factors combine to create a negative outlook in the Atlantic Basin, according to the hurricane update.
The accumulated cyclone energy index is approaching normal values for this time of year. Even with an uptick in activity in early June, as well as over the past few days thanks to Ernesto, this year’s storms have been weak and short-lived, according to Riskpulse Chief Science Officer Mark Russo.
The ACE Index is a metric meteorologists use to measure the severity of the tropical season. It takes the number, intensity and duration of storms into account.
“We’re entering the heart of the hurricane season, and the next four to six weeks are very critical here for overall ACE values,” Russo said. “The average ACE value is around 100, but last year it hit 225 to 230. We believe that this year will not be going that route.”
Riskpulse’s latest ACE estimate is below 100, with 75 to 100 being the most probable range.
The update emphasized that, even though a particularly active season may not be in the cards for the Atlantic Basin, individual storms can still pop up and have have a substantial impact.
Riskpulse’s next hurricane season update is scheduled for mid-September.