How Dust From Texas Ends Up on Your Windshield in Des Moines


A series of powerful storms have whipped up winds across the Southwest and southern Plains in the last few weeks, churning up vast clouds of dust that have turned highways into hazard zones. In the last month, at least 20 people have died in car crashes amid low or nonexistent visibility.

The impact of these dust storms stretched beyond the region. Strong winds carried the dust unusually far — hundreds of miles north and east — where it mixed with rain, leaving residents as far as the Mid-Atlantic puzzled by the orange residue coating their cars and homes.

Here’s a look at how a rare combination of drought and strong winds turned a relatively normal late-winter weather event into something far more unusual.

Dust storms are driven by winds that lift loose dirt up into the air — the drier the land, the less secure the soil.

They occur all over the world, mostly in the Middle East and North Africa. In Europe, it’s not uncommon for fine particles of sand from the deserts of northern Africa to get kicked up by warm, humid Saharan winds that blow from the south or the southeast across the Mediterranean Sea and into southern Europe. That dust can even get dragged as far north as Britain, where it’s sometimes referred to as “blood rain” because of its dirty hue.

These storms can also happen just about anywhere in the United States, including eastern Washington and California’s Central Valley. But they’re especially common in the desert Southwest and across the southern Great Plains, particularly in late winter and early spring. The activity there has long peaked in April, though research shows the season is shifting earlier with storms increasingly being reported in March.

Deserts, overgrazed land and areas experiencing drought are especially prone to dust storms. It’s no coincidence that most of the Southwest and southern Plains are experiencing some level of drought, and it’s especially bad in far West Texas.

In El Paso, there have been more days with low visibility from dust than clear ones so far this month, said Thomas Gill, a professor of environmental science and engineering at the University of Texas at El Paso. “It’s kind of the expected weather in spring, and we live with it,” he said. “But to have this dust that is so thick that you can barely see a block or two down the road and it looks like Mars, it’s really unusual to have a dust storm that bad, much less three in less than three weeks’ time.”

There have been three main storms this month that have upended daily life in parts of the Southwest, southern Plains and Chihuahua, Mexico: one on March 3 and 4, one on March 14, last Friday, and one this week, on Tuesday.

And each time, dust from this unusually intense succession of storms did something even more unusual: It was lofted up and carried hundreds of miles north and east to other parts of North America.

National Weather Service offices in Charleston, W.Va., and St. Louis have shared satellite images showing that dust from the Southwest had been swept up high into the atmosphere and then, as light rain moved through their regions, been pulled down to the ground. Last week, television stations as far away as North Carolina were talking about the “dirty rain” that had fallen from the sky.

Particles from Tuesday’s dust storm made their way to Iowa, where snow on the ground had a “brownish, yellowish tinge,” said Brooke Hagenhoff, a meteorologist with the Weather Service office in Des Moines.

The dust was carried so far because of the orientation of the storm and the strength of the winds, said Bill Line, a research scientist with the National Oceanic and Atmospheric Administration’s Center for Satellite Applications and Research.

These systems come from the West Coast and move up and over the Rocky Mountains, gaining strength and intensity, Mr. Gill said. Then they move into eastern New Mexico, the Texas Panhandle and western Oklahoma and Kansas, which is essentially the 1930s Dust Bowl region.

“As these storms start intensifying in that region, the winds from those storms can extend hundreds of miles out from the center of the storm, all the way to the Mexican border and beyond and then all the way across the Plains,” he said. “As they get more and more intense, the winds crank up.”

All three recent events lasted several hours, but experts agree the one on March 14 was the most severe, with winds over 80 miles per hour kicking the dust far into the sky and helping to propel it into regions that don’t normally see its effects. Aaron Ward, a meteorologist with the Weather Service, said an 83 m.p.h. gust was recorded in Amarillo, Texas — among the strongest ever measured by his office, with records going back 175 years.

The dust from that event was carried well into Ontario by the next day, said Mr. Line.

The March 14 wind storm didn’t only whip up dust, it also caused wildfires to rapidly spread across Texas and Oklahoma. In detailed satellite imagery you could see the thick dispersion of dust sweeping east as well as the darker milky gray smoke plumes rising above the brown dust.



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