Hurricane season forecasting is very difficult. Day to day tropical forecasting also presents its challenges. There are many variables that can aid the development of a tropical storm or hurricane and there are plenty of variables that could lead to a storm's demise.
One of those storm inhibitors is Saharan dust. Saharan dust is exactly what is sounds like. Sand, or dust being blown from Africa's Sahara Desert. The dust gets lifted into the atmosphere and typically moves westward off the coast of Africa and into the Atlantic Ocean on the heels of the easterlies.
Dust in the atmosphere is associated with dry air. Obviously, dry air prevents moisture from gathering ultimately leading to a significantly lesser opportunity for convection, or vertical development of clouds. This dry, sinking air can sometimes cover a large area of the Atlantic Ocean, and sometimes, even more of the Atlantic Hurricane Basin.
When that dry, Saharan dust is present, its sinking air would prevent a storm from developing. If a tropical storm or hurricane moves into an area of Saharan Dust then that dry air could get wrapped into the storm and eventually fall apart.
We monitor the Saharan Air Layer on a regular basis during the hurricane season. You can check it out right on our website.