August is here, which serves as the ramp-up in tropical activity in the Atlantic Basin.

This increase in activity continues until the peak of the Atlantic hurricane season on Sept. 10, and there are a number of weather factors that historically begin to shift in the basin during this time.

Why the shift?

There are a number of changes in the atmosphere that historically begin to happen in August, which leads to the spike in named storms in the Atlantic Basin seen in the graphic above.

Tropical wave chances increase: Tropical waves are areas of low pressure that form over Africa and move west into the Atlantic Basin. These disorganized lows don't have a closed circulation, but as they move into favorable atmospheric conditions, they can get more organized and become tropical storms or hurricanes. According to the NHC, 60 tropical waves track across the Atlantic Ocean each year. About one in five of them become tropical cyclones in the Atlantic.

(FOR MORE: Why tropical waves are important)

Dry, dusty air decreases: Speaking of Africa, rounds of dust from the Saharan Desert move west off the African coast. This dusty air is hot, dry and very stable. It serves as a cap that squelches tropical development all around it. But the tropical waves I just mentioned actually provide moisture to the desert, which stops the dust from flowing.

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(MORE: Saharan Air Layer)

Wind shear lessens: Wind shear, defined as changes in wind speed and direction as you move up in the atmosphere, can majorly disrupt the development of tropical systems. Historically, in August, the shear in the Atlantic Basin lowers, which allows for more storms to develop.

(FOR MORE: What is wind shear?)

Sea surface temperatures peak: The oceans take longer to heat than you may think. In the earlier months of hurricane season, oceans are lagging behind what may be experienced on land. But by August, the temperatures are reaching peak temperatures for tropical development, which lasts until early fall.

Instability increases: Instability is defined as the atmosphere's ability to create storms. The more unstable the air, the greater the chance storms will last long enough to become organized into a tropical system.

(MORE: Hurricane terms and definitions)

All of these factors bring increased chances of tropical systems developing in the Atlantic. Below you'll see a map that shows where named storms tend to originate in the month of August. The reds and purple are the areas you tend to see named storms form.

Recent August storms

August is no stranger to life-threatening storms, and we don't have to go back far to see some notable examples.

Hurricane Idalia: This storm rapidly intensified from a Category 1 to a Category 4 hurricane in just 24 hours Aug. 29-30, 2023. This storm devastated parts of Florida and spent four hours on land as a hurricane. This storm brought heavy rain, gusty winds and incredible storm surge to Florida. Power outages skyrocketed across the region. And even though this storm continues to impact further inland into September, its immediate impacts in Florida were substantial.

(RECAP: Hurricane Idalia)

Hurricane Debby: In August of 2024, Hurricane Debby peaked as a Category 1 hurricane, but its impacts were widespread after weakening to a tropical storm. The storm brought widespread rainfall of 2-7 inches and gusts up to 70 mph across the Big Bend of Florida and southeastern Georgia. The storm also brought a storm surge that was 3-5 feet above normally dry ground around landfall in Florida.

But, impacts continued as it moved into the Carolinas and eventually through the Northeast as a remnant low, showing you don't need an overly powerful hurricane to see devastating impacts.

It only takes one landfalling storm with significant impacts to designate the season as destructive. And remember that it can be "just" a tropical storm, not necessarily a hurricane, that can have significant impacts.

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