An incoming plume of dust from the Sahara Desert will create vivid, picturesque sunsets and sunrises from Texas to Florida over this week, according to AccuWeather meteorologists.
Thanks to a weather pattern called the “African easterly jet,” which consists of strong low- to midlevel winds in the atmosphere over central Africa, an enormous plume of dust has been airlifted and blown across the Atlantic Ocean. On Wednesday, satellite imagery from the National Oceanic and Atmospheric Administration (NOAA) captured a robust plume that stretched from the African coast to Cuba, a distance just short of 4,000 miles.
While the dust is expected to reach the Gulf Coast late this weekend, it may not be all that noticeable until next week when high concentrations arrive, according to AccuWeather Senior Meteorologist Adam Douty. “From southeast Texas to Florida are areas where [the dust] will be the most noticeable,” said Douty. “It will most likely cause the sky to appear milky white.” Douty said that the dust might be thick enough in a few areas to make the sky look hazy, but for the most part the dust will remain in the mid- to upper levels of the atmosphere.
Typically, the sky appears blue because the gasses that make up the atmosphere naturally scatter blue hues with shorter wavelengths than yellow, orange, or red. During the sunrise and sunset, the sunlight has to pass through more of the atmosphere because of the low sun angle. This makes the sunrise and sunset appear with a yellow or reddish hue. According to NOAA, “a heavy load of dust in the atmosphere can enhance this effect, leading to longer-lasting, duskier colors that cause vivid sunsets and sunrises.”
Nearly two years ago, in late June 2020, a monstrous Saharan dust cloud, dubbed the “Godzilla dust cloud,” swept across the Atlantic Ocean, bringing one of the most concentrated areas of dust scientists had seen in years. And while this most recent plume of dust isn’t expected to reach “Godzilla” status, it serves as a reminder that the frequency of these dust plumes will increase through mid-June and peak from late June to mid-August.
According to NASA, each year winds pick up an estimated 100 million tons of dust from the Sahara Desert and a large amount of it blows across the Atlantic Ocean, which can influence the weather. The time of year these dust plumes become more frequent is synchronous with the Atlantic hurricane season. These dust plumes can suppress tropical cyclone development over the Atlantic Ocean. According to NOAA, the dusty air has about 50% less moisture than the typical tropical atmosphere, and, as a result, can weaken an organized tropical cyclone or growing tropical disturbance.
Second, the warm air associated with the plume acts to stabilize the atmosphere, suppressing the formation of clouds. The dust suspended in the atmosphere absorbs the sunlight, which helps it maintain its warmth as it moves across the Atlantic. Lastly, the strong winds associated with the dust plumes can also disrupt or weaken a tropical cyclone or tropical disturbance.
While most of the dust from this plume will remain in the mid- to upper levels of the atmosphere, air quality levels can drop to moderate or even unhealthy from Texas to Florida. Those with respiratory issues are urged to limit the amount of time they spend outside once air quality drops to moderate or unhealthy levels. AccuWeather, through data provided by Plume Labs, a company acquired by AccuWeather earlier this year, allows users to monitor real-time air quality in a given location.
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