Trends over the last 18 hours have benefited snow lovers across the eastern half of PA, while not taking anything away from those out west. For the first time in a long time, both Pittsburgh and Philadelphia are under Winter Storm Warnings for a storm.
We’re still looking at a clipper transferring energy to the coast. The reason for the snow gap in Central PA is the Alleghenies to the west rise up in elevation, forcing precipitation to fall heavier. By the time the clipper reaches Central PA, it’s moisture-starved and the coastal low pressure mainly benefits eastern areas.
Roads will be immediately impacted as snow begins to fall, except near Philadelphia where marginal temperatures and more pretreating will fend off roadway accumulations for the first few hours. So this evening still looks fine to travel around Philadelphia…