The Alberta Clipper formed in the Midwest on Monday, Dec. 4, and will exit over the mid-Atlantic on Tuesday night, Dec. 5, AccuWeather reports.
According to the NWS' Pittsburgh station, a wintry mix is expected sometime later this morning and through the afternoon, before all precipitation turns to snow.
The most likely areas for the mix would be south of I-80, while further south, say south of I-70, the precipitation may change to all rain for a time this afternoon.
Less than an inch of snow is expected in Pennsylvania, the NWS says.
Snow showers are also expected in the northernmost parts of Maryland, the NWS said.
Tuesday night, Dec. 5 will be approximately 30 degrees with rain and snow showers set to begin early Wednesday morning, between 1 and 4 a.m., the NWS says.
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