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 Never mind the borderline temperatures or weird organization of this weekend's storm for a moment. One of the principal obstacles to a significant winter storm in the area this weekend may be lack of moisture. This morning's 72-hour precipitaton forecast map from the Hydrometeorological Prediction Center shows the heavier moisture south and east of our area. Convection -- i.e. thunderstorms -- down that way may cut off the moisture flow into Southwest Virginia. Furthermore, the double-barrel low-pressure structure that may develop ... two weak to moderate lows, one east of us, one west of us ... may further aid in cutting off deep moisture flow to the area. The dark green over most of the western half of Virginia represents .25-.5 inch of liquid equivalent. If that were all snow, it could be 3 to 5 inches; but it won't be, and most likely will be primarily rain with only weak cold air damming in place. Barring some significant changes, it looks like the best chance of snow this weekend will be upslope mountain snow showers on the back side of the system late Sunday night and Monday, which could bring a few more inches to eastern West Virginia and the higher elevations of far western Virginia. There is some threat of freezing rain or sleet Sunday morning as the precipitation edges in with a warmer air mass overriding the cold air at the surface, so be alert driving to church or elsewhere on Sunday.