The last couple of weeks have featured a few news stories on all the African dust in the Atlantic, some of which made it as far west as Houston and even Oklahoma City! Is it normal to see this much dust in the Atlantic? Yes! In the central U.S.? Well, maybe that part is a bit unusual.
It just so happens that we are running a Saharan Air Layer (SAL) Evaluation that started on 06/17/18 and will run until 09/30/18. The participants include the National Hurricane Center, Weather Prediction Center, Melbourne, Ruskin, Miami, Key West, San Juan forecast offices, and the Caribbean Institute for Meteorology and Hydrology in Barbados. The concept is to test the utility of many different dust or moisture products as it relates to the SAL events with subtopics focusing on convection, air quality, visibility, and lightning. By running an evaluation in this way (weather event focused), we hope to get valuable feedback from forecasters on which products perform well and which ones may need some work. We will also be comparing dropwindsondes during special Hurricane Research Division (HRD) flights to the NOAA Unique Combined Atmospheric Profiles (NUCAPS) to increase confidence in the soundings over the tropical Atlantic.
I have included two animations of the SAL outbreaks from 07/05/18 – 07/11/18. You may also notice Hurricane Beryl and Hurricane Chris forming on the edge of the larger outbreak that follows Beryl. This dust was pulled rather far north and got wrapped up in the circulation of Chris, leading to an increase in lightning (not shown, yet). Meanwhile, Beryl formed quickly, then dissipated quickly, but that appeared to be more due to the shear (very strong easterlies at low-levels), which caused decoupling from the convection.
Stay tuned for more updates on the SAL evaluation and a look at some of the products that are being evaluated in operations.
Thanks for reading!