The evening balloon launch by @NWS_BaltWash near Dulles shows a layer above freezing, but also dry air that will initiate evaporative cooling. Sfc temps will stay cold, but tracking warm air aloft will be key to where snow changes to sleet/freezing rain Thursday. pic.twitter.com/CF4ulOV2AP

— Tom Tasselmyer (@ttasselWBAL) February 18, 2021