Saharan dust stifles Tampa Bay’s afternoon showers, leads to heat warnings

The afternoon and evening showers that usually cool the Tampa Bay area this time of year will be scarce for the next several days thanks to a cloud of Saharan dust.

The dust has a good side: It clips the chances of tropical storm and hurricane formation.

And it has a bad side: Without afternoon showers and thunderstorms, our area bakes, and the heat index jumps to dangerous levels.

A heat advisory was issued for Hillsborough and Manatee counties on Thursday, prompting Hillsborough County officials to issue a news release encouraging residents to stay indoors.

The notice also encouraged residents to stay hydrated and to check in on neighbors or loved ones who might be vulnerable to the heat.

The heat index on Thursday afternoon was expected to reach up to 110 F. The heat advisory was in effect from noon until 6 p.m.

“Hillsborough residents without access to adequate air conditioning can find refuge in a variety of public places like libraries or shopping malls,” Hillsborough County’s news release states.

Meteorologists at Spectrum Bay News 9 said rain chances, which often are 50% or better during summer days in the Tampa Bay area, were only 20% for Thursday and Friday. They increase a bit to 30% on Saturday but will return to 20% Sunday. Rain chances don’t increase to 40% until toward the middle of next week.

Clouds of Saharan dust flow over the Atlantic to the United States from time to time. The dust results in dry, hazy air.

“It suppresses the ability for showers and thunderstorms to form because all that drier air just kind of puts a lid, so to speak, on the potential for thunderstorm development,” Austen Flannery, a meteorologist with the National Weather Service, said in a video posted to Twitter.

People who work or spend time outside during the hottest part of the day are encouraged to take precautions including rescheduling strenuous activities to the evening. The Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air-conditioned environments. Anyone overcome by heat should be moved to a cool and shaded location.

Heat stroke is an emergency, and residents can call 911 to access immediate care, the county said.