A large cloud of dust from the Sahara Desert blew into the Gulf of Mexico last weekend and will float over the Tampa Bay area for the coming days.
Covering parts of central and southern Florida, the dust cloud brings higher temperatures and hazy, dry air. Tampa will not see its usual rain and scattered thunderstorms this week due to the dust, said hurricane scientist Jason Dunion of the National Oceanic and Atmospheric Administration.
“That dust is the reason it’s going to be 95 degrees today,” he said.
According to Juli Marquez, a meteorologist for Spectrum Bay News 9, a patch of high-pressure air over Tampa is also contributing to the lack of rain this week. Dry air, combined with high pressure, makes it difficult for storm clouds to form.
The dust cloud is part of the Saharan Air Layer, a naturally occurring layer of dry, dusty air that sits about 1 mile above sea level. The layer forms as strong winds in Africa pick up dust from the Sahara Desert region and carry it west across the Atlantic. This particular plume of dust likely left the African coast about a week ago, Dunion said.
Dust clouds like the one Florida is experiencing now are a normal result of the Saharan Air Layer, Dunion said. Outbreaks of dust tend to ramp up in late June and peak in July and early August.
“It’s your typical dust outbreak, right over Tampa,” Dunion said. “We can expect more coming in the next several weeks.”
Along with heat and dryness, Floridians might also notice especially vibrant sunrises and sunsets as a result of the dust, Marquez said.
These dust clouds typically don’t pose a threat to human health. People with asthma or other pre-existing breathing conditions may notice the change in air quality more than others, Marquez said, but the air quality index shows moderate to good conditions in Florida this week.
The Saharan Air Layer actually helps protect Florida from tropical storms and hurricanes, according to meteorologists and storm experts. The dust suppresses storm formation over the Atlantic by ushering in dry air and blocking sunlight from heating the water, wrote Yale Climate Connections author Jeff Masters in an email to the Tampa Bay Times. Without moist air and warm ocean water, hurricanes have a harder time developing and sustaining themselves.
Dust outbreaks over Florida could be an important defense against storms this hurricane season, which scientists predict will be more active than average. But the dust clouds typically subside by mid August, Dunion said, right when hurricane season is reaching its peak.
It’s likely no coincidence that the height of hurricane season in late August and September comes as the dust clouds from the Saharan Air Layer dissipate, Dunion said. Still, residents of central and southern Florida could dodge some potential storms, thanks to the dust.
The current cloud over the Tampa Bay area is only the beginning of periodic dust outbreaks that will blow into the Gulf of Mexico over the coming weeks. Each outbreak is likely to bring vibrant sunsets, high temperatures and a break from the rain.
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