Clipper No. 3 in the series (though you could have called the Saturday-Sunday system a series of about 4 different clipper-like disturbances) dives our way late Monday into Tuesday. There are many complications that will lead to a trickier forecast. First off, the Arctic air mass is starting to moderate, so that the critical freezing line at the surface and up to a mile high will wander northward into or very near our region. Secondly, the main center of the next clipper appears likely to move north of our region, which means we could be on the “warm” side of the system, enhancing the pull of slightly milder air northward. Thirdly, there may be a low near the Gulf Coast that becomes at least partly involved and supplies a bit more moisture. Most forecast models do not show the northern and southern lows teaming up very effectively, so it’s possible this low stays to the south and is not a major player (other than perhaps consolidating the moisture flow to the south and drying up the air in between the two lows.) In all of that, it appears unlikely, as of late Sunday, that we are headed to a widespread snowfall, even a light one, late Monday and early Tuesday. But there could be a light mix of precipitation, with the best chance of snow north and west of Roanoke. The Hydrometeorological Prediction Center focuses the core likelihood of 1+ inch of snow in West Virginia (no surprise) with high chances west of Interstate 77 in Virginia, and lesser chances edging eastward into the western New River Valley. There will likely be some more upslope snowfall — northwest winds squeezing out moisture crossing the mountains — once this storm system passes.
We are heading for a steadily milder pattern through the week as highs push back into the 40s and 50s rather than recent 20s and 30s. A storm system late in the week will spread moisture again over our area by Friday and Saturday. From this distance, it looks to be a mostly rain situation, but ice/snow on the front end with lingering or wedged cold air and some upslope snow showers on the back end with colder air on the back side of the storm are at least possible. It appears we may be headed for another rainy storm in the days before Valentine’s Day. Long-range guidance has been conflicting on whether the mid to latter part of February turns warm or cold, but I’ll just pitch in that rumors of winter’s soon demise have been greatly exaggerated.
Chance of 1 inch of snow, rated from 0 to 10 snowflakes.
Roanoke: *** 3 snowflakes out of 10
Blacksburg: ***** 5 snowflakes out of 10
Outlook: Another Alberta clipper – a fast southeast-moving low-pressure system — like the ones that affected our area early Friday and again late Saturday into Sunday is headed down for late Monday night and Tuesday. Temperatures will be more marginal for frozen precipitation with it than the previous clippers, but it may connect with a southern low and tap a bit more moisture. Given marginal temperatures and the typical elevation/topography issues, I don’t expect Roanoke to get an inch of snow out of this. Blacksburg, again, could much more easily squeeze out an inch, though it’s a close call. I’m going with an even-odds chance for Blacksburg and two flakes less for Roanoke. There is a late-week storm that looks to be much milder than the first one. It’s not out of the realm of possibility for this to encounter a little cold air on its front side or to swing some cold air behind Friday or Saturday. It doesn’t change my thinking on the probabilities for the week too much, though.
Looking back: I didn’t catch onto the parade of Alberta clippers until after the snow meter had published. If I had, I would have gone much higher than three snowflakes for Blacksburg. Instead, 2.9 inches of snow fell there Friday through Sunday, which busted the snow meter (more than an inch of snow with less than 5 snowflakes) and gives me a loss. Roanoke only got 0.4 inch, officially, so I get a win for going three snowflakes and less than an inch falling.
Current records: 7-2 for Roanoke, 5-4 for Blacksburg.