UPDATE 4PM, 3/12: Snow has pulled away from Roanoke after leaving many 3 to 7-inch amounts -- some slightly lower and higher -- across the Roanoke and New River valleys. Snow is continuing to the east near Smith Mountain Lake and Lynchburg for a couple more hours, where similar amounts have been reported. Cold weather is expected to continue through midweek as the departing coastal storm wraps northwest winds into the area, particularly gusty on Wednesday, when they may also be accompanied by mountain snow showers. Milder, more typical March temperatures return by late week and the weekend. END UPDATE
UPDATE 1:20 PM, 3/12/2018: We haven't had a lot of winter storms or very big ones this season, but the ones we have had all seem to linger longer than we think they're going to. This one is doing the same, with steady snowing continuing in the Roanoke area past 1 p.m., though it is starting to slowly thin out to the west of us. We'll see that trend continue, however slowly, with the snow eventually tapering to flurries and ending. Snowfall has topped 3 inches officially at Roanoke (measured at WDBJ Channel 7 studio on Hershberger Road, near the airport) and there are many reports in the 5-7-inch range in the Blacksburg-Christiansburg-Radford-Pulaski area (generally what we call the New River Valley or "NRV) and south along the Blue Ridge in Carroll County. This storm isn't maxing out for all of its potential, but when the final flake has fallen, it may end up a tad higher than median expectations. Temperatures are near freezing and will rise a few degrees once the snow ends, which will start some melting (most paved roads are just wet or have just some scattered slush), but Tuesday and Wednesday will be unseasonably cold (30s/40s highs and 20s lows) so this mid-March mantle of white won't entirely disappear for a few days. END UPDATE
UPDATE 10:30 AM, 3/12/2018: Some heavy bands of snow have been moving across the New River and Roanoke valleys this morning, and may continue from time to time until noon or 1 p.m. or so. The spokes are of heavy snow are moving northeastward, however, the overall area of snow will eventually slide southeastward away from us, dwindling to flurries and ending during the afternoon. The reason we are being spared from /deprived of (depending on your point of view) a much bigger widespread snowfall is because the upper-level low is sliding more southeast than moving due east, and that's why the snow will get pulled away from us a little later. Still, it appears this is going to be pretty close to the 3-6-inch script for this event, with already 3-5 inches, locally more, in the NRV and along the Blue Ridge south of Roanoke, and 1-3 inches in the Roanoke Valley, with some spots up to 4 in the hills around the valley and a little less than 1 near the river, and snow continuing to fall and accumulate. END UPDATE
UPDATE 7AM, 3/12/2018: The Roanoke area is in a lull with mostly very light snow for the moment, but there is a growing band of heavier snow spreading from the I-77 corridor into the New River Valley that likely moves in a little later this morning. I've gotten several reports of 1/2 to 2 inches from the area, though only a dusting in some of the lower elevations of the Roanoke Valley. It's obvious we're going to have quite a bit of elevation difference in amounts today, as even a couple hundred feet higher is a little colder, the difference in a 32 and 33 in some cases. Many short-term models do show another 2-4 inches of snow by midday as far east as Roanoke and the Blue Ridge, it just may vary a lot how much of it sticks without melting slowly underneath from location to location. END UPDATE
The long-awaited and much-discussed snow is steadily overspreading the Roanoke and New River valleys early on this Monday morning, with a mix of rain and sleet changing to large, conglomerated flakes of wet snow as cold air builds in through the layers of the atmosphere above the surface.
Snow began between 3 and 4 a.m. in much of the Roanoke area, having already begun to the west and north and in higher elevations. It will continue to spread in areal coverage eastward, southward and into other lower elevations through the pre-dawn hours.
A winter storm warning continues in effect on this Monday for expectations of 3 to 6 inches of snow over much of the region -- a little more or a little less in some spots -- as an upper-level low passes to our south and a surface low-pressure system deepens off the coast of the Carolinas. The ability of snow to accumulate will depend on the intensity of its fall and on temperatures at a particular location, still somewhat above freezing in many locations where snow had begun falling in the early morning hours. Higher elevations, even a couple hundred feet, will generally see snow accumulate more readily than lower elevations.
Generally, the heaviest snow is expected through late morning, tapering in the afternoon, but timing is somewhat uncertain.
Grassy areas, trees and exposed objects will collect snow most readily, but some streets may be come slushy or snow-covered in heavier snow bands or as it persists moderately with temperatures dropping to near or below the freezing mark. If larger accumulations are realized, some tree damage and sporadic power outages may occur from the weight of the snow.