Saharan dust suppresses Atlantic Ocean hurricane formation

Seasonal changes could reduce flow of dust particles from Africa


JACKSONVILLE, Fla. – The 2018 Atlantic Hurricane season is off to a mild start with the development of only four named storms including two hurricane as of the beginning of August. Most forecasters believe this below-average trend will continue as we move into peak season.

While a number of factors are being blamed for the lack of hurricane development in the Atlantic Basin this season, they all coincide and influence one another. These crippling factors range from cooler sea surface temperatures in the Atlantic Ocean to higher levels of wind shear over the Caribbean to the development of an El Nino pattern over the Pacific Ocean, but the most subtle to contributor to a calmer season is likely the increase in Saharan dust over the Atlantic Ocean.

What is Saharan dust?

Saharan dust makes up the majority of the Saharan Air Layer. This shallow layer of air holds tiny aerosols like sand, dirt and dust that originate over the hot and dry Saharan Desert in Africa. Sometimes these particles are picked up by Easterly winds and blown westward into the Atlantic Ocean. 

How does Saharan dust impact Atlantic hurricane development?

Hurricanes and tropical storms rely on an abundance of moisture especially during their initial development. But the presence of stronger Easterly winds off of the coast of Africa tends to push drier air in the form of Saharan dust over the same region where storms often begin to form. Simply put, the dusts suppresses the moisture content needed to help the storms grow bigger and stronger. 

Dust & 2018 Atlantic Hurricane Development

Currently, Saharan dust is pushing as far west as Texas, therefore limiting the development of tropical activity from the Eastern Atlantic to the Gulf of Mexico.  As the atmosphere continues to change over the next few weeks, there's a chance that fewer dust particles will flow into the Big Pond. This time also coincides with the start of peak season, so while forecast are calling for fewer storms in comparison to last year Saharan dust won't likely keep the seas calm for the rest of the season.