Mobile, Ala. (WKRG) – Atlantic tropical development tends to be on the lower side in the months of June and July. This inhibition can be often connected to the prevalence of plumes of Saharan Dust.
The Saharan Air Layer (SAL) is described by the National Oceanic and Atmospheric Administration as a mass of very dry, dusty air that forms over the Saharan Desert in Africa during the spring, summer, and fall months. These plumes of very tiny particles can travel thousands of miles from their place of origin.
The SAL usually occupies a layer in the sky about 2-2.5 miles thick and is usually found around one mile up in the atmosphere. Dust plumes can be quite large in the early summer and extend across the Atlantic Basin reaching the Caribbean and Gulf of Mexico.
Occasionally, Saharan dust plumes can reach the Gulf Coast. This is usually accompanied by lower rain chances and hazy or smoky skies. In extreme concentrations, the dust can cause air quality issues for sensitive groups.
The presence of Saharan dust can also be a key factor in tropical development. Dust tend to inhibit tropical organization. For a mature tropical storm of hurricane, dust wrapping into the circulation can lead to weakening.