If that does happen, it would be the third officially measurable snow in Philadelphia in a week, and in coming so early that would constitute a rarity, if not a precedent.
Sunday, there is a 60 percent chance of rain before 7 a.m., then showers are likely between 7 a.m. and 1 p.m., the weather service said.
It will warm up a bit to above freezing on Saturday with highs in the upper 30s, officials said, but strong winds will still make it feel extra-chilly.
There's a chance for some risky snow squalls this afternoon and evening. Light to moderate snow can be expected to move into southeast MI into the early afternoon, with 1 to 2 inches possible west of I-75, according to information on the National Weather Service's Detroit/Pontiac Facebook page.
Saturday's high is expected to be in the low 30s, about a 20-degree drop from Friday's high of 50.
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Tonight: Partly cloudy. A slight chance of snow in the evening. South wind 7 to 11 miles per hour, with gusts as high as 22 miles per hour. Chance of precipitation is 80 percent.
Total snow accumulations of one to two inches are expected.
Baltimore and the District of Columbia, including its northern and eastern suburbs. Precautionary/preparedness actions. A Winter Weather Advisory for snow means periods of snow will cause primarily travel difficulties.
Snow is expected. You should plan on slippery road conditions with reduced visibility at times.