HOUSTON — It was predicted that the 2024 Atlantic Hurricane Season would be an active one. That proved to be true when Beryl became the easternmost forming June hurricane on record, the first and only Category 4 hurricane in June on record, and the earliest forming Category 5 hurricane in a calendar year on record. A day after Beryl made landfall, Colorado State revised its forecast predicting an even more active season.
We hear about Sarahan Dust every year around this time, here is an explanation for how it affects tropical development and possibly helps to lessen hurricane development.
The Main Development Region (MDR) is a stretch of the Atlantic known for development during the mid and late-summer months. It's an area above the equator between Africa and the Caribbean.
Development here is unusual in June because Saharan Dust is typically moving off the African coast, keeping water temperatures cooler and the air too dry to sustain development. However, Saharan Dust concentrations were fairly low through the month of June, allowing for some early season development with Beryl.
At the moment, Saharan Dust is moving over the open waters of the Atlantic, leading to a noticeable drop in activity through the end of July. This is only part of the equation explaining why conditions are turning quieter.
What Is Saharan Dust?
The name is as it suggests - Saharan Dust is dust that originates from the Sahara Desert in North Africa. So, where does it come from?
Thunderstorm development in the Sahel, a semi-arid region to the south, leads to large dust storms when these storms fall apart. Outflow from these storms kicks up dust and sand from the desert which gets lofted into the air and carried on trade winds across the Atlantic.
As the dust moves across the Atlantic, it blocks out sunlight when the concentration is high enough, leading to a drop in water temperatures. Additionally, the dry and dusty air lowers the humidity over the water, stunting cloud growth and preventing storms from becoming organized.
In addition to stunting tropical development, Saharan dust also carries nutrients that feed wildlife in the oceans, promoting a healthy ecosystem. Occasionally, dust can also make it over the Americas, leading to hazy skies and rarely poorer air quality.