Latest Forecast

Northwesterly winds of 12-25 mph with gusts up to 35 mph will usher colder air into northern MD and southeastern PA late this afternoon, and high temperatures will be around 10 degrees lower than Thursday with wind chills in the 20s. A secondary, Arctic front will then sweep through the region this evening, signal the arrival of a bitterly cold air mass later tonight into Saturday, and set the stage for a major winter storm on Sunday. Temperatures will plunge rapidly this evening and end up in the single digits above zero early Saturday morning. However, wind chills could be as low as 15 degrees below zero due to a 12-25 mph north-northwesterly breeze. Fortunately, winds will subside Saturday morning, but the cold will indeed be of the "dangerous" variety. Uninsulated and unprotected pipes could freeze or burst, and exposed skin could develop frostbite within 30 minutes or less. Thus, it will be imperative to dress in layers, cover up exposed skin, and limit time outdoors. A Cold Weather Advisory is in effect from 10 PM this evening through 10 AM Saturday. A Canadian high pressure system will settle over the eastern Great Lakes region on Saturday, and the deep, Arctic air mass combined with increasing clouds will prevent high temperatures from exceeding the mid-to-high teens. A complex, far-reaching and powerful storm system will track from the Deep South to the Delmarva coastline spanning Saturday night to Monday morning. To its north and west, a major snowstorm will unfold across the Lower Susquehanna Valley on Sunday. Snow should overspread the region from southwest-to-northeast between 10 PM Saturday and 2 AM Sunday, fall heavily at times later Saturday night through Sunday afternoon, and then taper off Sunday night. The snow may mix with or changeover to sleet south of the Turnpike and east of I-81 Sunday afternoon or evening before ending. Snowfall rates may reach 1-2" per hour in the heaviest bands on Sunday, and temperatures will only be in the teens to perhaps 20 degrees during the storm. Total snow and sleet accumulations should range from 8-12" inches across Lancaster County to 12-18" north of the Turnpike and west of the South Mountain Range. Roadways will be virtually impassable from Saturday night through at least Monday morning, and most schools and businesses will be closed on Monday. Avoid travel during the storm, and stock up on extra supplies, blankets and groceries now! Make sure you have a full tank of gas in your vehicle to keep water condensation from freezing inside fuel lines.