If I recall correctly, the week heading into St Pat's is the last week this area historically has gotten any snowfall of measurable height in a generation. Using a weather outlook guide, which I'm aware isn't accurate but it's better than nothing, the last shot DC has stands to be next weekend where the low is just close enough to the line to permit a reasonable dip and the slow moving rain arrives a day late.

Pardon my horrible meteorological skills but I would not be surprised if the individual 50% chance of a 0.25" precipitation at 32-35F lows over Friday/Saturday decided to marry themselves into 1" of snow, although I wouldn't bet it. Would be nice, though.