Winter is actually acting like winter.
A prolonged cold period is ongoing in the wake of an impactful, multifaceted winter storm on Sunday and Monday, with the possibility of more snow on the way Friday and Saturday.
Other than a week in mid-January last winter, we haven’t had this much winter to track since January 2022.
Let’s start with what may be next, as that’s foremost on most people’s minds.
Next train on the track?
A low-pressure system will track across the South late Friday into Saturday morning, a familiar track for significant snowfall in Virginia with cold air firmly parked to the north, augmented by the most recent snowpack over the Midwest and Mid-Atlantic regions. This path allows Gulf of Mexico moisture to be tossed into a cold air mass without as much of a warm layer developing above us that could bring sleet, freezing rain, or plain rain.
There are some questions, though, about the upper-level wind energy associated with this system, enough that this isn’t, at least yet, a clean-cut, nearly certain significant winter storm for Cardinal News’ Southwest and Southside Virginia coverage area.
It is unclear how much the upper-atmospheric pattern, namely the interplay of shortwaves in the northern and southern branches of the jet stream, will allow the storm system to maintain strength moving eastward. It may lose some of its lift as it moves east with lesser amounts east of the Appalachians compared to those likely farther west from Texas across Arkansas and Tennessee. But this is unclear.
The vast majority of computer model solutions spread at least an inch or two of snowfall across most of our region. Many of those bring more. A few mostly miss us to the south, though, and a decreasing few turn it so far northward that sleet mixes in.
So the system will probably bring snow to Southwest and Southside Virginia, but it might not be a lot of snow. Hopefully we’ll have a much better idea by Thursday night and Friday morning before it arrives.
A true wintry mix storm
The term “wintry mix” gets thrown around quite a bit by weather people.
Very honestly, it often means we’re not certain which precipitation form is going to be dominant, or we do have a pretty good idea but maybe one or both of the other two will show up briefly.
The Sunday-Monday winter storm was one of the rare cases when a large part of our region experienced all three forms of wintry precipitation — snow, sleet and freezing rain — in substantial amounts.
The reason this wasn’t a big areawide pure snowfall is that the low-pressure system responsible was headed almost directly at us, from west to east, rather than dipping farther south. In a lot of cases, especially in the weather patterns we experienced over the past two winters, this would have meant nothing but rain, or very brief icing at most. But Arctic air had filtered southward in such volume that cold air was pressed ahead of the storm, and was banked against the mountains.
The heaviest snow tracked a couple hundred miles north of the low track, through Northern Virginia. That left Southwest and Southside Virginia in a zone of shifting precipitation types, first snow as the initial moisture was condensed in deep cold air and could fall from cloud to ground as ice crystals. But as the low to the west swept in warmer air aloft, the snow eventually changed to sleet — snow melted into rain on the way down then refroze into ice pellets — and eventually freezing rain — snow melted into rain and only froze again once it landed on objects at the surface.
Snow was somewhat surprising in parts of Southwest Virginia eastward into Southside, even into northern North Carolina, where many locations picked up a quick 1-4 inches when only an inch or less was generally expected. More expected, snow only slowly changed to sleet and freezing rain north of the U.S. 460 corridor, angling southeast into Lynchburg itself, so many of those areas up to I-64 got 2-6 inches of snow.
The freezing rain proved all too worthy of its prior warnings, with many places seeing a quarter to a half inch of ice buildup, and at one point more than 100,000 utility customers lost power from the southwest corner east into central Virginia. Snow cover from the initial wave of the storm helped keep cold air in place at the surface sufficient for rain to freeze on objects at the surface rather than temperatures rising slightly above freezing.
The Roanoke Valley caught a break when a slightly deeper pool of colder air banked against the Blue Ridge and over the valley, allowing much of the nighttime precipitation to be sleet instead of freezing rain. That added another ½ to 1 inch to the inch of white iciness to the snow that had already fallen, and the ice on the trees was a little less severe, but still enough for some scattered power outages. Some areas north of U.S. 460 also kept more of a sleet mix and didn’t have quite the same level of power outage problems.
Arctic air has been reinforced in the wake of the storm, so whatever snow-sleet-ice accumulation still exists at many locations will not go anywhere fast. It will likely stay white through this week and part of next, with continued cold temperatures — another very cold morning with teens lows and some single-digits on Thursday — and the possibility of new snowfall come Friday night and Saturday.
Snow squall warning
For some areas along and west of the Blue Ridge, Sunday’s winter storm actually accumulated on top of leftover snowpack from two days before.
An Arctic cold front bringing a windy jolt of very cold air on Friday was accompanied by an Alberta clipper storm system, an upper-level low diving southeastward across the Appalachians from central Canada.
This triggered a series of strong snow squalls crossing the mountains.
Just about every Arctic cold front is followed by snow squalls triggered by upslope flow over the mountains, and that was an enhancing factor in this episode. But strong atmospheric lift and instability from sunshine warming surface air into the 30s and 40s, rising aloft into air many degrees below zero, also helped fire snow squalls of unusual strength that actually traveled some distance east of the mountains.
At mid-afternoon, the National Weather Service office in Blacksburg issued its first-ever “snow squall warning,” something like a severe thunderstorm warning for a sudden burst of heavy snow accompanied by gusty winds. This snow squall warning extended from southwest Roanoke County down Interstate 81 to northeast Wythe County, including the New River Valley towns of Blacksburg, Christiansburg, Radford, Dublin and Pulaski. Many locations in the warning collected a quick ½ to 2 inches of snow as visibility dropped to a few hundred feet for a short time.
Then the sun came back out, though there were additional snow squalls later.
Beyond the cold spell?
There is not yet a real thaw on the horizon, but perhaps some long-range hints we may get there by February.
After this week and early next week, the weather pattern may become more seasonably cold — lots of 40s highs, 20s lows — rather than the recent much-below-normal cold.
An Arctic air mass may dive into the central U.S. around Jan. 20 or so. That will be close enough to continue sending some pieces of colder air our way and perhaps occasional wintry precipitation risks.
Some long-range signals point to colder air focusing more on the western U.S. with warm high pressure building into the East by early February. But, as always, weather vision gets increasingly fuzzy the farther out we peer.
It’s also unclear, if the thaw does materialize, if this would essentially be an early spring arriving or if we would snap back into colder weather and wintry precipitation threats later in February or even in March.
By then, we will have the groundhog to help us figure it out.
Journalist Kevin Myatt has been writing about weather for 20 years. His weekly column, appearing on Wednesdays, is sponsored by Oakey’s, a family-run, locally-owned funeral home with locations throughout the Roanoke Valley. Sign up for his weekly newsletter: