An incoming cold wave could be the coldest temperatures of the 2024-2025 winter season. Daytime highs across Wyoming could drop below minus 20 before factoring in the wind chill.
For several days, northern Wyoming has been persistently cold. Now, the National Weather Service is tracking a high-pressure system of Arctic air that will envelop the entire state this week.
The temperatures accompanying it could be as cold as they get this winter
“I think the worst of the cold for the northern part of the state will ease a bit by the end of the week and the weekend,” said Cowboy State Daily meteorologist Don Day. “But at the same time, it won’t warm up a lot either. These colder-than-average temperatures could stick well into February and March, especially in northern Wyoming.”
Fairly Frigid
The high-pressure system moving across Wyoming carried dry, blowing snow across sections of the state that have already seen heavy snow over the last week. Once it passes over the Cowboy State, frigid temperatures will follow, felt across the state.
“We're expecting some of our coldest temperatures for the week in southeast Wyoming,” said meteorologist Shelby Fuller with the National Weather Service (NWS) Office in Cheyenne. “Highs in the teens and low temperatures in the single digits and potentially below zero on Tuesday night.”
It’ll be even colder in northern Wyoming, especially in communities close to the Montana state line. Day said temperatures could easily reach minus 25 and even lower with the wind chill.
“With Arctic outbreaks like this, temperatures can be super localized,” he said. “It could be 40 degrees in Cody and well below zero in Greybull. I think the range of temperatures will be between minus 15 to minus 25, especially overnight. With wind chill, many places will easily reach minus 30.”
Cold air is dense, so the lowest places tend to be the coldest. Meteorologist Joshua Rowe with the NWS office in Riverton said basins in western Wyoming should expect the next two days to be “fairly frigid.”
“We’re seeing lows in the negative teens and twenties in Jackson, Star Valley, and the Upper Green River Basin,” he said. “Big Piney, Pinedale, and the Bighorn Basin will be pretty cold as well, and it could reach as low as minus 34 in Yellowstone.”
Light, Fluffy, Blowing
There shouldn’t be much snow over the next week since the Arctic air mass will not have any moisture carried over from the Pacific Ocean. Whatever snow falls will be dry and light, presenting the usual hazards for drivers across southern Wyoming.
“Since the air is so cold, totals will most likely be on the lower side,” said Fuller. “It will be very lightly, fluffy, and blowable, so any little breeze is going to pick that up and cause visibility issues when driving.”
South-central Wyoming could see one to three inches of snow over the next few days, and as much as four inches in the higher elevations. Day cautioned that accumulations would be enough to cause some hazards on Wyoming’s major road corridors.
“The light now will come in little ripples, not amount to much, but there will be some accumulations,” he said. “Anyone driving along the I-80 corridor, I-25 from Wheatland to Torrington, should expect to see some snow while the northern part of the state will have flurries and bitter cold.”
Rowe said the highest amounts of snow will fall where snow is already on the ground. That’s also where temperatures will get the coldest.
“It’s warmed up quite a bit in central Wyoming in the last two weeks and melted most of the snow in that area so that it won’t be quite as cold there,” he said. “There will be widespread cold where there's already snowpack. But we won’t see much snow with this system due to the lack of moisture.”
Keeping Busy
February has already been a busy month for Wyoming weather, and that pattern will likely continue. Day said more snow is already in the forecast once the Arctic air mass moves on.
“There's another system that could bring some snow to western Wyoming late Thursday and into Friday and Saturday,” he said. “There could also be scattered snow across the state this weekend, so it's staying active.”
Rowe said the system at the end of the week probably won’t have the strength to make it over the Continental Divide, which means eastern Wyoming will have a chance to warm up after several days of subzero temperatures.
“The cold temperatures will clear out on Wednesday, so we could see daytime temperatures just above freezing from Casper to Buffalo,” he said. “Next week is looking pretty warm for most of the area.”
Meanwhile, southeast Wyoming could see another shot of dry, blowing snow at the end of the week. By the weekend, Fuller said temperatures could reach into the 40s.
“We’re still looking at cold temperatures, but warmer than highs in the teens and lows in the negatives,” she said. “The snow won’t be coming from another Arctic blast.”
Cold As It Gets?
Several subzero surges have occurred in January and February. Wyoming might not be out of the woods yet, but this week could be as cold as it gets this winter.
“By this weekend and next week, the Arctic air won’t be as cold,” Day said. “I don’t see a spring pattern, but there is some relief.”
Day said more Pacific weather patterns are on the horizon, keeping chances of snow high in the mountains. Those patterns could be strong enough to reach up and over the Continental Divide, bringing more snow to the plains.
Based on these extended forecasts, Day believes Wyoming’s weather will stay busy and snowy. It might not get as cold as it has been in the last several weeks, but temperatures could remain below average for quite a while.
“These patterns will stay really busy going into March, but it’s rare to get these Arctic outbreaks after the first week of March,” he said. “Will we see severe cold like this return? I don’t know, but at the same time, I don’t see temperatures moderating or going above average, especially in northern Wyoming. Warming up is going to be slow, slow, slow.”
The good news is that this Tuesday and Wednesday might be the end of negative double-digit temperatures this winter season. There are no guarantees, but Day believes the worst will be over after this week.
“This doesn’t mean we can’t go below zero again,” he said, “but if we look at the weather over the next three weeks, I would say this will be the coldest it gets.”
Andrew Rossi can be reached at arossi@cowboystatedaily.com.
