A drift of Saharan air will dry South Florida out over the next few days with rain chances as low as 10 percent mid week.
The National Weather Service in Miami is forecasting near record low levels of precipitable water, which is the measure of rain that would accumulate at the surface if all the water vapor in the air fell as rain.
Meteorologist Larry Kelly said normal precipitable water values are 1.8 to 1.9 this time of year, but they will fall to 1 to 1.3 through Friday.
“It will definitely be less moist and our dew points will come down to the low to mid-70s,” Kelly said. “The main thing with the drier air is the rain chances drop quite a bit.”
In West Palm Beach on Tuesday there is less than a 20 percent chance of rain. That drops to 10 percent Thursday. On Friday, rain chances are also 10 percent.
But even that is far below what’s normal for this time of year, Kelly said.
Typical daily rain chances are between 40 and 50 percent mid August, he said.
“The satellites are showing a large dusty air mass moving up through the Caribbean,” said Joseph Prospero, professor emeritus at the University of Miami’s Rosenstiel School of Marine and Atmospheric Sciences. “We’ve had some very intense outbreaks and we can still get spotty rain.”
Prospero and Jason Dunion, a meteorologist with the University of Miami who tracks Saharan dust, said this summer has been dustier than normal.
Neither could say for sure what would cause more Saharan air this year.
Dunion said they will be looking at,the strength and position of the subtropical ridge over the Atlantic and recent drought trends over Africa.