Winter Weather Advisory issued December 23 at 9:28PM EST until December 24 at 5:00AM EST by NWS Pittsburgh PA

Heavy snow is expected overnight along and near Interstate 80.
Although there is high confidence that snow amounts in the
Interstate 80 area should remain at or below three inches, the heavy
snow will fall in a short time period (just a few hours), leading to
rapid buildup on roads.

In the ridges, a brief burst of snow is possible just before
sunrise, with a rapid transition to a prolonged period of freezing
drizzle, which could lead to a light glaze of ice by late Tuesday
morning.

* WHAT…Brief heavy snow expected. Total snow accumulation up to
three inches.

* WHERE…Portions of northwestern and western Pennsylvania.

* WHEN…Until 5 AM EST Tuesday.

* IMPACTS…Roads, and especially bridges and overpasses, will
likely become slick and hazardous as snow falls at a high rate
over a few hours. Plan on slippery road conditions.