ST. LOUIS — Drizzle, one of the smallest forms of precipitation, led to pile ups and cancellations that stretched from Sunday night into Monday morning.
Drizzle usually does not cause problems, but when surfaces are cold enough to freeze it quickly ices everything over and unlike snow, it's hard to see.
"Freezing drizzle is one of those things that is really light and doesn't necessarily show up on radar," Weather First Chief Meteorologist Scott Connell explains.
Freezing drizzle is sneaky and while the 5 On Your Side Weather First team knew it was coming, apparently drivers did not.
"The road tends to look wet," Connell explains. "But when temperatures are in the 20s and there is no treatment on the roads, then you get glazing."
Glazing happened Sunday night and Monday leading to a jack-knifed semi on Interstate 70, another semi accident on Interstate 44 and a multi-car pileup on Interstate 64.
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The dangerous conditions also lead 150 schools and districts to cancel class, others switched to remote learning.
"By the time we got to 6, 6:30 and 7, things were really glazing over especially north and west of St. Louis," Connell recalls from Sunday evening.
When the Monday morning commute rolled around, Weather First Meteorologist and Traffic Anchor Garry Frank said no one was going anywhere fast.
"Things were moving very slow, it was about half an hour slower than normal at least," he said.
Winter weather usually causes problems, but freezing drizzle is a hidden issue.
Frank said, "you didn't see it, you drove on it and ran into a slick sheet of ice."
Connell said it is not unusual to see freezing drizzle.
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