Dust from Sahara Desert tracking towards Gulf: What does that mean for our weather?
Dust from the Sahara Desert could help keep a lid on Atlantic hurricanes, at least for the next few days.
Hurricane forecasters on Wednesday continued to watch a plume of dust that had moved off Africa’s west coast and was blowing westward across the tropical Atlantic.
The dust originated in the Sahara Desert, and it can help keep tropical systems from developing.
The dust could make it all the way toward Florida and possibly into the Gulf of Mexico and in the past has made its presence felt as far west as Alabama and Texas.
The National Weather Service in Miami was anticipating the dust to reach South Florida this weekend or early next week.
It’s nothing that unusual for this time of year. Forecasters said the dust “would be pretty typical for late June or early July in our area, but the only impact aside from slightly hazy skies would be the drier air dampening daytime convection a bit.”
According to NOAA, the Saharan Air Layer, or SAL, typically peaks from late June to mid-August. During that time period, some dust plumes can reach as far west as Florida, Central America and even Texas. And the dust clouds can be big enough to cover big swaths of the Atlantic.
One of the bigger dust plumes caused spectacular sunsets in Alabama almost this exact time in 2020. Here’s a satellite image from 2020 of the dust over the Gulf of Mexico:
Dust that originated in the Sahara Desert made it into the Gulf of Mexico on June 25, 2020. Sahara dust can make it to Alabama, but it doesn’t happen all that often.
The Saharan Air Layer can form over the desert anytime from the late spring into the fall and move in batches westward across the tropical Atlantic every three to five days, according to NOAA’s Atlantic Oceanographic and Meteorological Laboratory.
The dust travels about 1 mile above the surface and can form a layer that is 2 to 2.5 miles thick.
If it makes it as far as the U.S. it can cause skies to look hazy and make sunrises and sunsets particularly pretty, thanks to the dust in the air filtering light.
But of more importance, especially right now, is that the dust can help choke off tropical development before it gets going, thanks to the dry air.
According to NOAA “the warmth, dryness and strong winds associated with the SAL have been shown to suppress tropical cyclone formation and intensification.”
The National Hurricane Center was monitoring two tropical waves on Wednesday, but both had low chances of becoming tropical depressions or storms:
There are two tropical waves being monitored in the Atlantic on Wednesday. Both have low chances of becoming tropical depressions in the next seven days.National Hurricane Center
However, that trend may not hold. NOAA forecasters are anticipating a very active hurricane season in the Atlantic, with 17-25 named storms possible.
A many as 13 hurricanes could form this year in the Atlantic Ocean, according to forecasters.NOAA
Will the dust make it to Alabama? The National Weather Service hasn’t mentioned it in forecast discussions so far and instead of dry air is expecting humidity levels to rise here over the weekend, leading to increased rain chances.
An area of high pressure will be parked to the west of Alabama, and winds here will be rotating clockwise around that high, blowing generally in from the north or northwest. That should keep the dust away from the state for now.