Death and taxes are the only certainties in life, according to Benjamin Franklin.
In Wyoming, there’s one more certainty: high winds, which will soon be sweeping across southern Wyoming.
The National Weather Service (NWS) has issued a High Wind Alert for most of southeast Wyoming between Wednesday evening and Saturday. Meteorologists anticipate “a prolonged, significant high wind event,” with gusts as strong as 85 to 100 mph in the most wind-prone areas.
“Our guidance is showing the worst of the wind starting at 6 a.m. Thursday, peaking around noon to 3 p.m.” said meteorologist Ryan Zawislak with the NWS office in Cheyenne. “It’ll gradually diminish Thursday evening but stay elevated through Friday and even into Saturday.”
This is one of those instances where hurricane-force winds will be inescapable in southeast Wyoming, especially the problematic spots on I-80 and I-25. No matter what, it’s going to be windy.
“The winds are going to howl,” said Cowboy State Daily meteorologist Don Day. “I would call it a typical high wind event. There's nothing unusual about it, but we need to be prepared for it. It’s 100% going to happen.”
Wind Aloft Blow Below
The source of this week’s windstorm is strong winds aloft in the jet stream, 30,000 feet above Wyoming. Day said the winds moving over the Cowboy State will be “in excess of 160 to 175 mph.”
“Some of that energy will be transported down to the lower elevations when conditions are right,” he said. “This pattern really favors the central and southern counties.”
How much of the energy will manifest this week? Day didn’t want to speculate on the upper thresholds of the wind gusts, but sustained winds between 55 and 60 mph across the region are “a certainty.”
“When you hit the sustained wind speeds like that, studies show that localized gusts of 70, 80, and 90 mph plus will probably occur,” he said. “That’s where terrain and wind angle make a difference, and those areas that are more prone to those wind gusts are definitely going to be impacted.”
Zawislak said the strongest winds will be in the most wind-prone areas of I-80, such as the stretch between Arlington and Bordeaux. He doubted there would be any gusts in excess of 100 mph, but that doesn’t mean it’s out of the realm of possibility.
“It’s more likely that wind gusts will top out around the low 90s in that area,” he said, “We’re only anticipating wind gusts of 65 mph in Cheyenne, but winds are still going to be gusting into the 70 to 75 mph range along I-25 and I-80.”
The Usual Suspects
Unlike other windstorms, which last only a day or two, this windstorm is shaping up to be a prolonged event. Zawislak said there will be some fluctuations in intensity between Wednesday and Saturday, but it will remain persistently windy.
“It’s going to be a persistent upper mid-level jet stream that’s going to keep the winds persistent,” he said. “It’s the catalyst for strong winds that will be pushing south.”
Drivers, especially those with high-profile vehicles, will want to be aware of where the winds will be strongest. Day cited the usual list of wind-prone areas that will get the worst of this windstorm.
“The I-25 corridor between Wheatland and Cheyenne, down to the Colorado state line, will definitely be impacted,” he said. “That stretch of I-80 between Laramie and Rawlins, around Elk Mountain, will be hit hard, and there's that stretch west of Laramie where the road has to bend to the north to start to go around the mountains. That one spot will be a real problem with the westerly winds.”
The “good” news is that southeast Wyoming will remain dry throughout the prolonged windstorm. There’s no precipitation anticipated with this system, so there won’t be the additional hazards of slick pavement and black ice on the highways.
That comes with its own hazards, however. Southeast Wyoming is already experiencing record-low precipitation, which means strong, gusty winds could accelerate the spread of wildfires.
Back To Before
Cheyenne got 5 inches of snow last week, which was one of the most significant winter weather events of this record-breaking dry winter. Day said the last week was “great” for southern Wyoming in terms of precipitation, but that isn’t carrying over into this week.
“There will be a little bit of precipitation behind this on Saturday night and Sunday, but not much,” he said. “The big winner this week, in terms of snow, will be the northern counties of the state.”
There was widespread snow across northern Wyoming on Tuesday, with up to 4 inches possible in Cody, Sheridan, and Sundance. Day said the Bighorns, Black Hills, and Yellowstone Plateau will “do really well” by this week’s snowy weather, which will help rebuild some of the snowpack they’ve lost since December.
After that, Wyoming will endure another week of above-average temperatures and below-average precipitation. Another blocking ridge of high pressure is forming over the Pacific Ocean, preventing colder air and moisture from flowing into Wyoming, Colorado, and other western states.
“The worst thing that could happen after we get all this beneficial moisture is another block, and that’s exactly what’s happening,” Day said. “We’ll have another week of warm and dry before we get active again, so unfortunately, next week is a bit of an interruption.”
How much of an interruption? Southeast Wyoming could be flirting with temperatures in the low 70s next week.
Unavoidable
The NWS is showing “increasing confidence” that this week’s wind event will be “high end” and “impactful.” Wind gusts between 80 and 100 mph, and possibly higher, are possible in the most wind-prone areas of southeast Wyoming.
High Wind Watches have been issued for other areas of Wyoming, particularly in the Bighorn Basin, for Thursday. Those winds will be less extreme, maxing out at around 60 mph.
Neither Day nor Zawislak would confidently predict how strong the winds will get on Thursday, the peak of this system, but they agreed that they’ll be persistent and widespread for the duration.
There’s no escaping it. It’s going to be dangerously windy in Wyoming this week.
“Unlike snow, the one thing about wind is that the chance of it happening is 100%,” Day said. “It would take an act of God to prevent this.”
Andrew Rossi can be reached at arossi@cowboystatedaily.com.
