Saharan Dust Cloud Crosses Atlantic Ocean, Threatens Florida

A massive plume of Saharan dust, the largest seen so far this hurricane season, is on its way across the Atlantic Ocean. This dusty giant is expected to reach the Gulf of Mexico and Florida by the end of the week, and forecasters say it could play a significant role in dampening storm formation.

The dry, dusty air associated with the Saharan Air Layer (SAL) is known to absorb moisture, which is a crucial ingredient for tropical storms and hurricanes. Experts believe this particular plume will hinder storm development as it travels from Africa towards the Caribbean and potentially reaches Florida.

While this might be welcome news for those hoping to avoid a stormy season, meteorologists caution that the impact of the SAL is temporary. These dust plumes are a common occurrence in the Atlantic basin during late June and early July, and their influence usually wanes by mid-to-late July.

What is Saharan dust?

The vast Sahara Desert, encompassing a staggering 3.5 million square miles across Africa, acts as a giant source of dust. This dust, known as the Saharan Air Layer (SAL) by the National Oceanic and Atmospheric Administration (NOAA), forms during the warmer months, from late spring to early fall. These immense dust clouds can travel incredible distances, impacting regions thousands of miles away from their African origins. Interestingly, the warmth, dryness, and strong winds associated with these dust clouds have a documented effect on suppressing the formation of tropical cyclones.

How does Saharan dust influence weather, climate, and hurricanes?

Saharan dust influences weather, climate, and hurricanes through extremely dry air that weakens storms by promoting downdrafts, the African Easterly Jet that increases wind shear and disrupts storm structure, and warm temperatures that stabilise the atmosphere, suppressing cloud formation. The mineral dust absorbs sunlight, maintaining the warmth of the Saharan Air Layer as it travels across the Atlantic and further inhibiting tropical cyclone development.