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The cold front that is pushing through overnight tonight into Monday, kicking off mountain upslope snow showers in its wake, is the fourth in the past two weeks. It looks like that No. 5 in the series will push through about Thursday and No. 6 will go through around Sunday. Each one will bring a new reinforcement of colder air, and fire up snow showers on the western slopes of the Appalachians (some of which may bleed over onto our side). In between, sunny, dry but chilly days can be expected. There's no sign now of any kind of southern-tracking storm system bringing abundant moisture into the cold air. There might be something a little wetter developing toward the middle of the following week (about the 10th) but it could just as easily end up turning north into the Ohio Valley the way this weekend's storm did.

If we get a widespread measurable snow the next week or so, it will probably have to come from a stronger "Alberta clipper" system diving southeastward. Really potent Alberta clippers that can spread a few inches of snow across the area are infrequent, but the odds go up some as we enter December. 

In short: The unseasonably cold pattern continues, but at least through the next week, it doesn't look an especially icy or snowy one.

Early this morning, the winter weather advisory was expanded to including counties up and down the Blue Ridge, including in the Roanoke and New River valleys, mainly for localized icing at higher elevations. It is unlikely we'll see ice in the floor of the Roanoke Valley before it expires at noon, just a cold, cold rain, but some of you at a higher elevations around the edges may be getting light icing. Be careful if you are traveling any roads that take you above 2,500 feet today.

We missed a widepsread ice storm by a narrow margin on this system. But at least we're getting some needed rain.

 A narrow strip of counties along the Blue Ridge ... including Floyd, Carroll and Grayson counties in Virginia ... has been placed under a winter weather advisory for the remainder of tonight. Temperatures have dropped to below freezing in some areas in those counties, allowing light icing to accumulating as freezing rain, freezing drizzle and sleet continue to fall. I-77 travelers going through Fancy Gap should take particular note.  Though some localized icing can't be ruled out elsewhere, particularly in higher elevations, most other locations in Southwest Virginia are above freezing, so thoough some sleet has fallen this evening mixed with rain, it is not likely to cause travel difficulties.

It's only Nov. 29 folks ... we've got about 4 more months of these occasional winter weather threats to go.

As moisture begins to move in over a cold layer of air at the surface, do not be surprised if you see some snowflakes, sleet pellets or a little freezing rain overnight and early Sunday. But temperatures will likely hang a little above freezing in most areas, and warmer air aloft will most likely switch everything to rain almost everywhere by mid-morning Sunday. Late Sunday night, cold air will come screaming in again behind a blustery cold front, and there will be a chance of snow showers into the day Monday.

It looks like a brush with wintry precipitation, not a slap of it.

 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.

We've been expecting precipitation (primarily rain) over the weekend for several days, but the whole situation is looking a lot more complicated than we were thinking earlier, with multiple disturbances, phasing jet streams, and borderline temperatures across our area. I'm still thinking this is going to be a mostly rain event in our area, maybe starting as sleet or snow late Saturday or early Sunday, with the low-pressure system passing west of us and drawing in warmer air aloft over somewhat-above-freezing air at the surface. But there is just enough uncertainty and intrigue in how it may come together to keep a wary eye on it. I'll post a little more detail on it as it comes into better focus.

Compared to recent days, Thanksgiving looks to be sunny and comparatively mild, with low to mid 50s possible. Neither Roanoke nor Blacksburg have topped 50 since seemingly balmy highs of 65 and 61, respectively, back on Nov. 15. The overall trend for the next couple of weeks continues to be below-normal temperatures, but it appears we will moderate some over the next few days. So maybe we'll have typical late autumn chill entering the holiday season rather than January-like cold.

Winter storm watches and winter weather advisories are up for eastern West Virginia counties just west of the border with Virginia as Round 3 of mountain snow showers begins (the first round was a week ago today, the second late Thursday and early Friday). Up to 10 inches may fall in western Greenbrier County, West Virginia ... the Quinwood area. As usual, a few snow showers may bleed over into the New River Valley, possibly even a ground-whitening snow squall or two, while a few flurries or even briefly heavier snow showers could drift into the Roanoke Valley. Let me know if you get measurable snow at your location.

Don't be surprised to see a few pellets of sleet or some brief icing of cold metal objects this morning in localized areas as moisture moves in on top of cold surface temperatures. But the same winds bringing in the moisture from the Gulf of Mexico will also bring in warmer temperatures, and so today and tonight will see a lot of cold, but above-freezing, rain. A cold front moving through tonight will swing winds to the northwest and trigger familiar snow showers over the mountains of West Virginia and western Virginia, a few of which may spill over into the New River and Roanoke valleys.

A third round of mountain upslope snow showers is due to arrive on Monday night and Tuesday. Like before, the best chances of accumulating snow will be on west-facing slopes and in higher elevations near the Virginia-West Virginia border and, especially, in eastern West Virginia. (Does the Hydrometeorological Prediction Center snowfall forecast map at left look familiar? The blue is a 10-39 percent chance of 4-plus inches, the green a 40-69 percent chance. Looks like the last two snow shower events. More snow for West Virginia ski areas.) Like before, there is a chance that a more intense upper-level disturbance moving through the northwest flow could rack up higher snow totals in a localized area or even spread snowfall farther east. Unlike the last two systems, this system will involve a rather potent surface low over the Great Lakes dragging a cold front through. The system will sweep in slightly milder air ahead of it, so anything that falls on Monday will likely be rain -- though sleet or freezing rain can't be ruled out entirely, especially in colder valleys or right as the precipitation begins. Once the front pushes through, cold northwest winds will kick up again, snow showers will begin to form as these winds glide up the western slopes of the Appalachians, and another blustery week of weather will set in for Thanksgiving.