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| Stranded vehicles after Illinois' dust storm on May 1 (Photo by Thomas DeVore, TMX, via Reuters) |
By definition, a dust storm is a "massive wall of sand, dust and grit — often a mile or higher and as much as several hundred miles long. . . . The storms can be accompanied by 60-mph winds, visibilities of barely a few feet and a suffocating concentration of dust particles that can pose a respiratory risk to virtually anybody," reports Matthew Cappucci of The Washington Post. "They can lead to deadly pileups on interstates and can render airports inoperable until conditions improve."
Farming and meterology are involved. Discussing the May 1 storm with USA Today, meteorologist Chuck Schaffer said, "It's been very dry across this area really for the last three weeks. The farmers are out there tilling their fields and planting. The top layer of soil is quite loose." Cappucci explains: "Dust storms form when strong winds loft dust into the air. Those strong winds are usually the result of thunderstorm outflow or exhaust — the cool, dense and dry air exiting a thunderstorm and surging ahead of it that kicks up dust along the storm's outflow boundary.' The dust acts as a tracer marking the wind-shift line. Anyone in the dust storm's path will spy a massive shelf of dust, which will race toward them with 40- to 60-plus-mph wind gusts and a drop in temperatures. Behind that initial outflow boundary, heavy rains within the thunderstorm can combine with remnant dust in the air to form muddy raindrops."
Farming and meterology are involved. Discussing the May 1 storm with USA Today, meteorologist Chuck Schaffer said, "It's been very dry across this area really for the last three weeks. The farmers are out there tilling their fields and planting. The top layer of soil is quite loose." Cappucci explains: "Dust storms form when strong winds loft dust into the air. Those strong winds are usually the result of thunderstorm outflow or exhaust — the cool, dense and dry air exiting a thunderstorm and surging ahead of it that kicks up dust along the storm's outflow boundary.' The dust acts as a tracer marking the wind-shift line. Anyone in the dust storm's path will spy a massive shelf of dust, which will race toward them with 40- to 60-plus-mph wind gusts and a drop in temperatures. Behind that initial outflow boundary, heavy rains within the thunderstorm can combine with remnant dust in the air to form muddy raindrops."
The impact can be great. "If a person is caught outdoors, the dust can be very problematic from a respiratory standpoint," Capucci reports. "The biggest threat from dust storms comes on the roadways. Erratic winds and abrupt drops in visibility can happen in seconds. The National Weather Service recommends drivers' pull to the side and stay alive' if they're passing through an affected area when a dust storm hits."
Where do most U.S. dust storms take place? "They're relatively frequent occurrences in the Desert Southwest, mainly in Arizona and New Mexico," Cappucci adds. "They also can make appearances on the Plains if there are existing drought conditions. The soil is more earthen over the central United States and less sandy, so lofting granules is more challenging. The drier the topsoil, though, the easier it is to lift. . . . Sometimes derechos, or extremely windy thunderstorm complexes that track long distances, can induce their own dust storms. That was the case on May 12, 2022, in Iowa, Minnesota and the Dakotas."
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