Will Wyomingites be giving thanks for warm weather over the Thanksgiving holiday, or will they be paralyzed by grounded planes and closed highways?
Meteorologists say it's still too early to get into the specifics, but it's looking more like the latter.
After several weeks of unseasonably warm weather, a significant winter weather system is poised to turn Thanksgiving into a winter wonderland. Temperatures will drop, snow could cover the entire state, and travel could be impacted nationwide.
"We are definitely seeing an ill-timed change next week," said Cowboy State Daily meteorologist Don Day. "It's far enough away that I'm not confident to say a lot or a little, but I would definitely say there's going to be some winter weather, accompanied by snow, into Thanksgiving."
In The Broad Strokes
With Thanksgiving a week away, it's still too early for a definitive forecast. However, Wyoming's meteorologists agree that there's a shift on the horizon.
"Temperatures will definitely be dropping next week," said meteorologist Joshua Rowe with the National Weather Service (NWS) office in Riverton. "A lot of things are going to have to come together just right for there to be significant snowfall, but there's definitely potential that this could be the first snow of the season for some locations."
Rowe said the NWS's Climate Prediction Center has been calling for above-average precipitation and below-average temperatures across Wyoming during the last weeks of November and the beginning of December. At least one of those will be true by Tuesday.
"We've got daytime highs in the mid to upper 30s east of the Continental Divide on Tuesday," he said. "Wednesday will be quite a bit cooler, with some locations staying below freezing."
Many meteorologists had anticipated this change earlier in November, but most of the winter weather up to this point had shifted eastward, keeping Wyoming warm. However, there's no denying what's coming.
"We're seeing enough of the changes taking place that it's going to be hard to stop them," he said.
How Low Can You Go
Matthew McLaughlin, general forecaster with the NWS office in Cheyenne, said the weather patterns that dictate Wyoming's weather are looking more active. When they reach Wyoming, they'll be carrying plenty of cold air from Canada.
"We have a couple of wave troughs, which generally bring us more winter-like storms at this point in the season," he said. "We are going to see a more active season and some colder temperatures, especially right around Thanksgiving time."
McLaughlin noted that while daytime temperatures will be noticeably colder starting next week, he was more concerned about how low overnight temperatures will drop. Wyomingites will be waking up to considerably colder temperatures than they've experienced so far.
"I'd say the more significant drop is in our overnight temperatures," he said. "We could get down into the teens overnight, especially on Wednesday and Thursday. We'll really start to notice the drop going into Monday and Tuesday."
Freezing overnight temperatures could have a significant impact on daytime travel. Since Thanksgiving is one of the busiest travel days of the year, Wyomingites will want to review their travel itineraries.
Overnight Ice
Where there's cold, there could be snow. The incoming weather systems have the potential to carry snow across Wyoming, and early indications suggest there's a strong possibility.
"There's going to be snow," Day said. "The first question is how much, and that'll depend on where you are, but the pattern that's evolving is certainly going to reintroduce snow into the high country, and the amount of cold air has the potential to put snow on the ground below that."
Rowe doesn't expect much, if any, snow accumulation across most of Wyoming, but that could change between today and Thanksgiving. The systems are in motion and still developing.
"If the moisture moves through overnight, there's going to be a better chance for it to accumulate," he said. "If it moves during the day, most of it will probably melt. Even with daytime temperatures in the low 30s, there probably won't be a whole lot of accumulation, unless we get some heavier showers, and we can't predict that far out.”
A lack of snow accumulation shouldn't be the takeaway for Thanksgiving travelers. Day's concern is that this moisture will cover roads and runways with black ice, especially with the below-freezing temperatures overnight.
"There'll be enough snow to make roads slick in parts of Wyoming," Day said. "There will definitely be some challenges, and not just here. A lot of the Western US, the Midwest, and the northern plains states are going to see this change to winter weather."
Cold (And Grounded) Turkey
Day expects the middle of the nation will be hit the hardest by this change. Anyone flying into or out of airports in Chicago, Minneapolis, and Detroit will want to keep an eye on what's developing.
Denver could also be hampered by this seasonal shift. McLaughlin said the corridor between southeastern Wyoming and Denver International Airport doesn't look too bad now, but it could change.
"I don't know about significant driving hazards, but right now it doesn't look too bad," he said. "Right now, it doesn't look too bad, but we do have the possibility of a couple of inches of snow. Depending on where these systems track, it could influence Colorado traffic."
Day's advice for Thanksgiving travelers was to anticipate winter weather conditions and continue checking local forecasts throughout their trips. A lot can change overnight, let alone in the next week.
"Holiday travelers need to stay on top of things," he said. "Don't let two days go by between checking the forecast. You need to be aware that things are going to be variable in terms of timing, especially on Monday and Tuesday."
The Definites
With a week until Thanksgiving, most meteorologists aren't confident enough to give a definitive forecast. However, they're all confident that the seasonal change they've anticipated will be here by Thanksgiving.
"It's definitely going to be colder, and there's definitely an increased possibility for snow with these colder temperatures as these systems move through," McLaughlin said.
Looking further out, there are even more reasons to be wary of winter weather. Day said a bigger winter blast is brewing and will reach Wyoming after the holiday.
"There's another storm system arriving the weekend after Thanksgiving," he said. "That stormier, colder pattern looks to go right into the start of December, so the pattern that's led to this three-week period of warmth and dryness is going away."
Rowe said the jet stream is slowly shifting southward, setting up a "typical La Nina weather pattern for winter," creating "a trough" that funnels cold air and moisture from Western Canada into the Intermountain West. That's the setup he and other meteorologists are monitoring that will bring winter weather to Wyoming.
"We'll see if that lasts beyond the middle to the latter half of next week, but it does look a lot more active here in the weeks ahead," he said.
Plenty Of Winter Ahead
Many Wyomingites have questioned Day and his long-range forecast for the 2025-2026 winter season, which called for a colder, snowier winter beginning in mid-November.
One reader, who sent an email to Cowboy State Daily, said Day “needs to find a better model” for his winter forecasts, saying he “was wrong last year when he predicted a cold, snowy winter” and the winter weather he anticipated during the second half of November “has failed to arrive — again.”
"Don Day was wrong last year when he predicted a cold, snowy winter, and now the cold he said was coming for the second half of November has failed to arrive – again," said the reader, Julianna Babcock-Souza of Casper.
"He needs to find a better model, as it seems that the one he is using is not accurate."
Day acknowledged that this November has been warmer and drier than “usual”, and that warmth has persisted longer than he anticipated.
"There's no denying that November has been extremely warm and dry up to this point," he said. "A lot of it has to do with the way these weather patterns have evolved, especially out in the Pacific, but also that systems normally coming out of Canada that would venture south into the Rockies have been mostly directed into the Great Lakes and the Northeast."
Nevertheless, Day said this isn't without historical precedent in Wyoming. He chalked these concerns up to "weather anxiety."
"We're overly enamored with averages and what people say are 'climate normals,'" he said. "I can point to many Novembers that were the exact opposite of this one, and I can find several Novembers, going back 30 or 40 years, that are just as warm as this one. We’ve got to remember that you go through these extremes."
Based on his historical analyses, Day said the first three weeks of November "don't really mean anything" when it comes to indicating the course of Wyoming's winter. He's sticking to his long-range winter forecast and expects to be giving thanks by Thanksgiving.
"I know people are getting antsy," he said. "The skiers, snowmobilers, and ice fishermen feel that things are out of whack. There's plenty of potential for plenty of winter to satisfy people's winter cravings. Late November and early December are when things get a bit more sporty, and we'll start seeing that next week."
Andrew Rossi can be reached at arossi@cowboystatedaily.com.
