Winter's One-Two Punch: Behind the Storm, a Dangerous Flash Freeze

On Sunday morning, thousands of utility customers were without electricity in Connecticut, where freezing rain had damaged trees and power lines.

Gov. Ned Lamont warned residents that temperatures were expected to fall by 20 degrees or more by Monday morning, and urged them to stay off the state’s roads so plows could clear them of snow before they froze over. He also urged people to clear their own driveways while they can.

The flash freeze was taking hold farther to the west. In State College, Pennsylvania, the National Weather Service reported Sunday morning that the temperature on the roof of its office had fallen to 24 degrees from 32.4 degrees in about an hour.

The Arctic air moving in behind the storm was expected to deliver freezing temperatures as far south as Tallahassee, Florida, and snarl travel across most of the Northeast, even in areas where the storm dropped little or no snow.

“Anything that remains liquid is going to freeze rather quickly, so there will be dangerous travel conditions,” said Rich Otto, a meteorologist at the National Weather Service’s Weather Prediction Center in College Park, Maryland.

More than 10,000 people in Connecticut were without power Sunday morning, according to Eversource and United Illuminating, two utility companies, in large part because so much of the storm’s precipitation in the state had come in the form of sleet or freezing rain. Otto said the trouble could multiply as the frigid winds pick up during the day.

“Those kind of winds blowing on those power lines and trees that are already stressed from the weight of the ice, I think, is going to be problematic,” he said.

Farther north and farther inland, the storm mainly dropped snow. As of Sunday morning, the greatest total reported was in Lake Desolation, New York, north of Albany in the southern Adirondack Mountains, where 16 inches fell, Otto said.

This article originally appeared in The New York Times.