Dangerous Travel: Snow, Sleet, Freezing Rain in the Hudson Valley

The National Weather Service updated its Winter Weather Advisories early Monday for Rockland, Putnam and Westchester counties that extend until Tuesday morning.

• Putnam County could get 3-5 inches of snow with an overlay of ice.
• Rockland County and northern Westchester could get 2-4 inches of snow with an overlay of ice, the NWS says.
• Southern Westchester could get up to an inch of snow with a glaze of ice.

IMPACTS...A SLOW THAW OF FROZEN GROUND WILL LIKELY RESULT IN ICING OF UNTREATED ROAD SURFACES AND WALKWAYS THIS EVENING INTO LATE TONIGHT...MAKING TRAVEL DANGEROUS.

This is going to be messy, meteorologists say. As the arctic air that made the weekend so cold moves out, warm air from the Atlantic Ocean will move in. That will first cause snow, and then as different cloud layers warm up, it will change to either sleet or freezing rain.

What happens next depends on how persistent that arctic air is.

“This could result in an extended period of freezing rain and sleet… something we will have to monitor,” says Bill Potter of Hudson Valley Weather. “Most of the data has the freezing rain changing to plain rain by sunrise on Tuesday. While this is likely… we should be very careful with this scenario. The computer models have a history of underestimating the resilience of arctic air in the past, and led to longer periods of icing than expected. We will need to watch this very closely on Monday night, because if the ice holds on longer in the Hudson Valley, we could see significant impacts for the Tuesday morning commute.”

Snow should start between 1-4 p.m. and become steady, then mix with freezing rain or sleet, leading to snow-covered and icy roads. Overnight, sleet, freezing rain or just plain rain could glaze roadways, and the slow thaw of frozen ground will also cause icing.

“Even a few hours of snow will have no trouble sticking to sidewalks and roads due to the cold from this weekend,” said Kristina Pydynowski, AccuWeather Senior Meteorologist.

MAP: accuweather.com