Massive clouds of Sahara Desert dust are moving over the Atlantic toward Central and North America, with the possibility of reaching Florida and other states, including Texas, this week.
The dust has covered parts of the Caribbean, including the Dominican Republic, Cuba and Haiti, and is projected to reach states along the Gulf Coast, like Mississippi and Alabama.
“The dust is due to a two to 2.5-mile-thick layer of the atmosphere, called the Saharan Air Layer, crossing over the Atlantic Ocean,” the National Oceanic and Atmospheric Administration (NOAA) said Wednesday. “The warmth, dryness and strong winds associated with this layer have been shown to suppress tropical cyclone formation and intensification.”
When the dust gets to the U.S., it can cause “hazy skies as well as vivid sunrises and sunsets as the sun’s rays scatter the dust in the atmosphere,” according to NOAA. The agency added that the dust can also “suppress thunderstorm development over locations where the dust is especially thick.”
The dust moves across the Atlantic from Africa every year, often called the Saharan Air Layer (SAL), which forms during late spring, summer and early fall, according to NOAA.
“SAL outbreaks can form when ripples in the lower-to-middle atmosphere, called tropical waves, track along the southern edge of the Sahara Desert and loft vast amounts of dust into the atmosphere,” said Jason Dunion, a University of Miami hurricane researcher who works with NOAA’s Atlantic Oceanographic and Meteorological Laboratory.
“As the SAL crosses the Atlantic, it usually occupies a 2 to 2.5-mile-thick layer of the atmosphere with its base starting about 1 mile above the surface,” Dunion said Sunday.