Wintry Disturbance Hits Northeastern U.S.

A wintry disturbance will continue eastward, buffeting the northeastern quadrant of the nation with light snow, freezing rain, and plain rain through Tuesday night. 

Warm and humid air from the Gulf and Atlantic will keep flowing northward today following a Canadian high pressure system over the Northeast. A weak layer of cold and dense air at the surface will force the humid air to wring out over the Lower Midwest through Appalachia today, the Mid-Atlantic tonight, and New England through Tuesday, bringing a wintry mix followed by rain to millions of people. 

In some areas, precipitation will melt and then refreeze as it dives through sub-freezing temperatures, forming corridors of sleet and notably freezing rain. 

Due to the often sub-freezing temperatures of this chilly surface layer, snow melting above the ground could regather into other forms of wintry precipitation in some areas, namely sleet and freezing rain. The Appalachian Mountains will slightly enhance this cold layer effect, essentially damming the cold air east of its ridges and expanding the area of ice-related impact in parts of the Mid-Atlantic Piedmont. However, warmer temperatures will continue to shove northward as the storm slides eastward, converting most wintry precipitation to rain well before it exits and melting any wintry glazes or coatings. 

By the time the storm exits, nuisance ice accumulations will have temporarily glazed areas from the Lower Midwest, through the Alleghenies, and parts of the Mid-Atlantic. Icing across these areas will remain well below a tenth of an inch, but morning traffic could be impeded in narrow areas north of the Ohio River this morning and across much of Appalachia and the near Piedmont on Tuesday morning.  

Snow accumulation through Tuesday will also be light, mostly leaving a slushy coating to inch across Lower Missouri Basin through Appalachia, central Virginia, and the Mid-Atlantic into southern New England. Locally higher snowfall of 1 to 2 inches could pepper central Appalachia and the Lower Alleghenies into central Maryland and Washington, D.C. 

So far, Winter Weather Advisories and Winter Storm Warnings have been posted from southern Indiana to western Maryland and up through central Pennsylvania, including areas encompassing the Appalachians in those states.

Be sure to download the WeatherBug app to stay up to date on the latest on this changing weather. It’s never too early to have a supply kit packed in case of inclement weather. A simple kit including a weather radio, water, blankets, batteries, and non-perishable food items will go a long way in the event of a power outage. It’s always best to avoid traveling in rough weather as the roads will be dangerous.