By Kyle Imhoff
Assistant Pennsylvania State Climatologist
The month of December ended with near seasonal temperatures and above normal precipitation across much of the state (except for the far southeast). As the first full week of 2017 continues, the mild weather that has been observed early in the week will transition to much colder weather for the end of the week and the weekend.
Scattered rain/snow showers will persist across much of northern and western Pennsylvania for the remainder of the day with temperatures dropping into the teens and 20's overnight. Some snow showers will linger in the north/west early on Thursday as a fast moving disturbance will bring more widespread snow showers, or even a period of light snow, to the rest of the state by Thursday evening. The highest snow totals will be in southern Pennsylvania, with 1-3" expected in most places by Friday morning. Behind this disturbance, very cold weather will ensue through the weekend. Across northern PA, temperatures will struggle to reach 20 degrees F by afternoon from Friday through Sunday. Widespread snow showers will persist during this time across the usual lake-effect snow areas of the north/west. Temperatures will rebound back to more seasonal levels (highs in the 30's and lows in the 20's) early next week as high pressure builds into the region. Current model guidance indicates that the remainder of the month will be relatively wet and slightly milder than normal.