The 2020 Atlantic hurricane season had one of the most active starts in history, with three named storms forming by June 2 for the first time ever. But the tropics have been quiet ever since.
You can thank dust from the Sahara Desert for that.
A massive dust storm that’s been moving west from central Africa is creating a pocket of dry air. That dry air is slowing down tropical activity as it passes through the Atlantic Ocean, and it could last for the next couple of weeks.
Rick Davis, a meteorologist at the National Weather Service’s Ruskin office, said the slow-moving dust is “robbing the air of all its moisture.” Tropical storms and hurricanes rely on air that is both warm and moist in order to form.
The occurrence is called the “Saharan Air Layer” by the National Oceanic and Atmospheric Administration. It’s a common phenomenon that lifts dust particles from the desert up 5,000 to 20,000 feet above the earth. What follows is little rain, no tropical systems and — eventually — stunning sunsets.
“One unique aspect of the dust will be our sunsets being incredibly vivid,” Davis said. “Saharan dust is orange and red, so as the sun sets through the haze you’ll get bright, brilliant sunsets.”
The dust is currently approaching the Windward Islands, which are the Caribbean’s easternmost landmasses. Davis said the dust will reach Tampa Bay around Wednesday and will bring warmer-than-normal temperatures for three to 10 days.
While these dust storms generally happen multiple times a year, Davis said the one moving toward Florida now is larger than usual. It will move from the Atlantic to the Caribbean, then all the way across Florida, Texas and Mexico until it eventually dissipates in the Pacific Ocean.
The dust can sometimes cause a thick haze to hang in the air over Texas, Davis said. Other times the iron that’s in the dust can feed into deadly algae booms in the Gulf of Mexico, like in 2018, when the dust contributed to scores of sea life deaths around Florida for more than 14 months.
Though the dust will provide a short reprieve from tropical systems, Davis warned that it will have no lasting impact on the rest of the 2020 hurricane season, which is expected to be more active than normal.
The months of August, September and October account for 93 percent of Category 3 or stronger hurricanes in the Atlantic. Forecasters already predict that there will be no presence of El Niño this season, which causes wind shear that tears storms apart as they form in the Atlantic. There may also be no more dust to slow down storms.
“Have a plan in place,” Davis said. “Let Cristobal and the active start be a warning. The tropics tend to get more active in July and August. There may be no dust in the atmosphere then.”