Mystery substance coats cars, homes throughout St. Louis and metro-east. What is it?
Some St. Louis and metro-east residents had a frustrating start to their Friday morning when they found their cars coated with a gray, muddy substance.
A meteorologist says the dusty film likely was carried via winds from the American southwest and deposited on areas that saw light rain in the morning.
Eastern New Mexico and Texas have experienced high winds and dust storms this week, whipping dirt into the upper atmosphere, said Marshall Pfahler, a meteorologist with the National Weather Service in St. Louis.
The fine dust particles drifted toward the St. Louis region in winds and then fell to the ground and onto vehicles during a spotty, light rain Friday morning.
“It definitely traveled a way to get here,” said Pfahler, who lives in St. Louis. “I woke up this morning and I had little dirt spots all over my car.”
If it had rained harder, the residue would have washed right off, he said.
Rodney Rednour of Marissa said his truck and vehicles throughout the were covered with the dust Friday morning throughout the southeastern St. Clair County town.
“I’ve never seen this before,” he said. “I don’t know what it is.”
But he was relieved to hear the National Weather Service’s report that the prime suspect in this mystery is a bunch of dust.
Pfahler noted it was just the right combination of atmospheric conditions to whip up the dust, haul it to the St. Louis area and then allow it fall back to Earth. He doesn’t believe the dust from about 1,000 miles away is hazardous.
“It’s more of an annoyance for people to have to wash their cars,” he said.
Jannie McCready, the city administrator for Tilden, said the dust explanation makes sense to her because as she drove to work Friday morning in a light rain, she had to turn on her windshield wipers to clear the “milky mud” coating her window. She also saw the material on her office windows.
Kaydence Hook, who works at the Casey’s convenience store in Tilden, said vehicles all over town were coated with the dust.
This story was originally published March 7, 2025 at 5:14 PM.
