Sometimes an especially warm Christmas is called a “green Christmas,” as opposed to the much more widely discussed and culturally promoted snowy “White Christmas.”
But in truth, this time of year with the leaves off the trees, even a balmy Yuletide is in reality a “gray Christmas.” The sky may be blue, but “Blue Christmas” already has another Elvis-crooned meaning in our holiday lexicon.
Whatever crayon wrapper label it carries, this particular Christmas is setting up to be among the warmest few on record for much of Cardinal News’ Southwest and Southside Virginia coverage area, and it will quite likely be the single warmest Christmas on record at many locations in states to our west.
A large dome of high pressure is expanding northward and eastward from the southwest and central U.S., which will bring some incredibly warm temperatures relative to Christmas norms and even previous record highs to many locations in the central U.S.
The warm air will not quite fully take over the northeast U.S., much of which is getting a reinforcement of cold and snow on this Tuesday, but Virginia is far enough south and west to get under this tent of warmth with widespread 60s highs likely on Christmas and over the weekend, possibly skipping over what may become a rainy Friday of 40s and 50s.
Standing record highs for Dec. 25 include 78 at Abingdon (1982, though no data before 1971), 74 at Danville (2015 and 1955), 74 at Tri-Cities Airport in Tennessee near Bristol (1982), 72 at Lynchburg (2021 and 1982), 69 at Roanoke (2021), 68 at Blacksburg (1964), 67 at Wytheville (1982 and 1964), 63 at frequent regional cold spot Burke’s Garden (1982) and 74 at common regional hot spot John H. Kerr Dam in Mecklenburg County (2015).
Current projections suggest Thursday’s highs will come in a few degrees under these, with perhaps a little higher spike over the weekend, unless clouds and showers intervene. No widespread pouring rain is expected this week, but some stubborn frontal boundaries and upper-level disturbances circling the big central U.S. high may kick up some light showers from time to time this week, perhaps just enough to stymie record-setting warmth. Friday may even see a wedge of cooler air from the northeast bank against the mountains for a spell.
Still, for our region, this is a stunning flip from what was one of the coldest and snowiest first halves of December on record, as we discussed last week.
Why so warm this Christmas?
Everything that made the first half of December so cold and snowy for our region and much of the northern, central and eastern U.S. has played out and moved aside.
The atmospheric regime that has taken over, for now, is influenced by complex pattern interactions globally including the continued presence of La Niña (colder than normal sea-surface temperatures in the equatorial Pacific). It features much less high pressure blocking in the northern latitudes in the right place to push cold air southward consistently into the eastern U.S. as a large dome of warm high pressure balloons over much of the contiguous United States.
This particular pattern is timed just right to reach its maximum for warm-air coverage and intensity over the U.S. right on Christmas, though the pattern itself may linger in some form even into January. It might get a little less publicity if it were peaking on Dec. 22 or Dec. 28 or Jan. 5 instead of right at Christmas.
The climate change angle to this is that, while natural variability means that not every Christmas or any other time period of winter will be unusually warm for any given location, periods of milder air in winter are in general becoming more expansive in size and duration, increasing the odds that a particular location will have milder temperatures at Christmas more often.
For our region, Christmases in 2015, 2021 and now likely 2025 having the kind of warm temperatures that typically occurred about 20 years apart in the past is loose evidence of this perhaps becoming more of a trend. But, of course, the frigid Christmas weather of 2022 and the widespread snow along and west of the Blue Ridge, including the Roanoke Valley, in 2020 show natural variability is still very much in play.
What happens after this
In general, there are three ways this might play out the rest of this winter.
The first possibility is that what’s happening over Christmas is the default pattern for the rest of winter. There may be some cold pushes and wintry precipitation now and then, especially over the northern and eastern fringes of the nation, but mild and dry would be the overriding theme at least into February and possibly all the way to March as this warm high pressure dome doesn’t fully go away, supported by stubborn global atmospheric patterns and historical analogues.
Secondly, the whole warm air regime could collapse by mid-January like a dam break and a much colder pattern ensues for a large part of the nation for the latter part of January into February.
Thirdly, and what I consider most likely at this juncture, is that there will be a push and pull between what we’ve seen in the first half of December and what we’re getting at the end of December throughout the season. This will lead to up-and-down temperatures and variability, and probably the development of some significant storm systems, the track and intensity of each individual system determining who gets rain and who gets snow.
There isn’t much signal of any kind of full collapse of the mild pattern yet, but there are some growing signals of high-pressure blocking repositioning in the northern latitudes which could lead to the warm high-pressure dome eroding or being pushed westward as 2025 concludes or 2026 begins.
So it will probably get colder in our region after this warm spell, maybe even as early as next week, but whether that means just less mild or typical seasonable cold or something more wintry remains to be seen.
Warm Christmases precede big snowstorms?
Snow lovers put out by the lack of Christmas whiteout can take some solace in what seems to be an unusual correlation between some of our warmer Christmases and large snowstorms occurring weeks later in January or February.
For example, Lynchburg hit 67 degrees on Christmas in 1965 then got 31 inches of snow in January, including two storms in the 10-13-inch range. Roanoke’s high on Christmas 1965 was a mild but not extreme 60, with a monthly record 43 inches of snow ensuing in January, including two storms over a foot and two more around 7 or 8 inches.
That, of course, happened in the excessively snowy 1960s, but 1982, 2015 and 2021 were also notable warm Christmases followed by significant snowstorms in January or February.
A warm Christmas in 1982 — I remember this personally for tornadoes and flooding growing up in Arkansas — preceded a memorable foot-plus snowstorm over much of Virginia on Feb. 10-11, 1983. Similarly, our warm Christmas in 2015 was followed by a snowstorm of 8-14 inches across most of the region on Jan. 22-23, 2016, and then 4-8 more on Feb. 14-15.
The most recent Christmas warmth of 2021 followed this pattern to a lesser degree with widespread snowfalls of 3-8 inches on Jan. 3 and Jan 16 that could have easily been 8-12 if not starting as rain in the first case or mixing with sleet in the second.
Another curious occurrence is the couplet years of 1982 and 1983 and 2021 and 2022, when, in both cases, one of the warmest Christmases on record was followed a year later by one of the coldest.
There of course is no hard-set expectation that a warm Christmas this year will be followed by cold and snow early in the year to come or by a frigid Christmas next December; it is just interesting how often these events have happened.
Whatever you think of a not-white and not-cold Christmas, try to get out and enjoy not needing a heavy coat for a few days this holiday season.
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.
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