1:15 PM | **Still a long way to go in the snowstorm; especially, across the northern suburbs**

Discussion

Short wave energy is just now rounding the base of an upper level long wave trough and it is causing significant intensification of a low pressure system near the Mid-Atlantic coastline. The latest 12-hour 500 mb height change map (above) depicts the location of the center of the short wave energy (marked with an X) over Kentucky which is headed to the east coast. This key upper level system will provide many hours of strong upward motion in the Mid-Atlantic region and the result will be snow, heavy at times, right into the evening hours from DC-to-Philly-to-NYC. As the low pressure system slowly pulls to the northeast and intensifies, the snow will linger - not ending until late this evening in DC, after midnight in the Philly metro region, and towards morning in the NYC metro region. Bottom line, snow accumulations of 6-10 inches can be expected in the northern (Maryland) suburbs of the District with 3-6 inches to the south of DC. Quite an amazing winter weather pattern has only just begun and will continue for the next 7 to 10 days or so with multiple Arctic air outbreaks and snow threats.