A trough moving across Wyoming brought high wind to portions of central Wyoming. The highest reported wind gust was 92 mph at Red Canyon along South Pass in the Wind River Mountains.
Every event with a place to put it; 6 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS RIW wrote it up.
A trough moving across Wyoming brought high wind to portions of central Wyoming. The highest reported wind gust was 92 mph at Red Canyon along South Pass in the Wind River Mountains. The strongest wind occurred in the wind prone areas near Casper where wind gusts as high as 81 mph were reported. The Lander Foothills, the Green Mountains and Johnson County.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Riverton, WY wrote its last area forecast discussion before the first event at Dec 24, 3:45 PM MST, 3 hours 15 minutes earlier. Its key messages:
Area Forecast Discussion National Weather Service Riverton WY 345 PM MST Wed Dec 24 2025 .KEY MESSAGES... - Mild temperatures today, with more record highs possible. - An approaching weather system brings more snow to the western mountains and strong to high wind from South Pass and Muddy Gap through Casper. - Another weather system follows on Friday, with seasonable temperatures likely for the weekend and into next week. && .UPDATE... Issued at 1220 PM MST Wed Dec 24 2025 No major changes to the forecast for the next 24 hours or so. EFI/SOT is highlighting portions of western Yellowstone (Pitchstone Plateau and the northwest corner) for snow, so have upped amounts slightly there, but caution doing too much as models seem to be overdoing snow with many systems so far this season. Also continued to drop precipitation chances east of the Divide as high-resolution models correctly have precipitation struggling to make it over the mountains. && .DISCUSSION... Issued at 212 AM MST Wed Dec 24 2025 Twas the shift before Christmas, and all through the weather station, meteorologists were looking at observations from across the nation. Combined with weather models, radar and data from satellite, trying to bring forecasts for travelers through the day and night. And on the inside of the humble Riverton weather abode, there were difficult forecast decisions to be made at it showed. Another Pacific weather system was approaching from the west, And some of the possible travel impacts made the forecaster stressed. Snow was likely over some of the higher mountain passes, and strong wind could slow travel to speeds as slow as molasses. And hopes of a White Christmas for most would be dashed, as recent mild temperatures are not expected to crash. Now back to your regularly scheduled weather discussion. Things are largely quiet right now, as they were much of yesterday. The main story today continues to be the abnormally warm temperatures, as much as 30 degrees above normal. Casper had their third warmest December high temperature in station history yesterday. We are now up to 53 record highs this month at our 9 official climate sites. Seven of our official sites are having the warmest first 24 days of the month in their stations history (including Lander, which has records dating back 134 years). Riverton is more than 4 degrees above the second warmest period. And the two stations that aren't (Casper and Buffalo) are ranked 2nd and 3rd. And with southwest flow continuing today, we will likely see more record high temperatures this afternoon. As for precipitation, a few showers will develop west of the Divide, but nothing of note, at least until around sunset. Things get more active tonight. We had two decisions to make tonight in regards to potential highlights, one for wind and one for snow. We will start with wind. Part of the reason it has been so warm is the strong southwest wind, which has been at times very strong. We will have a decent setup for strong wind again today. The pressure gradient will tighten ahead of an advancing Pacific cold front and trough. The 700 millibar winds are expected to increase to 50 to 60 knots ahead of the system. We will also have the right front quadrant of an 100 knot jet streak providing some downward forcing. In the realm of probabilistic guidance, areas from Muddy Gap through Casper look to have at least a 2 in 3 chance of exceeding gusts of 55 mph. So, we went ahead and upgraded the Watch to a Warning and added a couple of zones. We added Casper Mountain for one, with at least a 1 in 2 chance of gusts past 65 mph. The other zone was a bit of a tougher decision. This is the eastern slopes of the Wind River Mountains. We thought about a Winter Weather Advisory instead. However, southwest flow is more conducive to western portions of the range. We also thought about impacts. The main road in this area, South Pass, only has around a 1 in 4 chance of 2 inches of snow or more. And with 700 millibar temperatures expected to remain above zero Celsius through most of tonight, it would be mainly rain for precipitation. With the busy holiday travel day, we felt the main impact would be high wind. So, we went with high wind. There could be some blowing snow problems as well though, especially Christmas morning as somewhat cooler air moves in. There will likely be some advisory amounts of snow in the higher elevations, but impacts there this time of year would be rather limited. Now for the snowy side of the system. Steadier precipitation will move in this evening as the front and better upper level forcing approach the area. The 700 millibar temperatures should remain above zero Celsius through around 8 pm tonight, when the arrival of the front begins to lower the levels. The real drop doesn't come until around sunrise Christmas morning though, when they fall to around minus 3 Celsius, putting snow levels around 7000 feet. This should keep snow levels above the valley locations, except possibly toward the end of the event when there could be a small accumulation. The main impacts would be the passes, especially Togwotee Pass with its almost 10000 foot elevation. Here, as well as Teton Pass, with at least a 1 in 2 chance of 6 inches or more of snow, we have hoisted Winter Weather Advisories. And, given the favorable upslope flow, added on for the western Wind River Range as well. If this was a random day, we may have held off. However, given the holiday travel concerns, along with some gusty wind bringing blowing snow, we went ahead and issued. The heaviest snow would fall between midnight and noon on Christmas day, when the trough axis passes and the best jet dynamics move through. And finally, some models are indicating negative lifted indices in western Wyoming, so we can't rule out a stray thunderstorm Christmas afternoon. Otherwise, Christmas Day looks to be another well above normal day temperature-wise, with more record highs possible. There could be a few showers, but the downsloping flow should keep most areas east of the Divide mainly dry. Wind should decrease somewhat in the afternoon as the system moves away. And as a result, the chance of a white Christmas is basically zero. Another system will be on this one's heels for Friday. This one has somewhat cooler air with it and should put an end to the record highs for most locations. But not during the day on Friday, when we may have one more day of record highs. As for the next system, this one has more jet forcing with it and as a result precipitation looks to be more of the banded variety and hard to pinpoint. With the cooler air with this system (cooler, but not cold, especially by Wyoming standards), there could be some snow in the valleys as 700 millibar temperatures of minus 5 Celsius put snow levels at 6000 feet. And east of the Divide, there could be strong wind again, although high wind is more questionable. We will finally put an end to the warm weather on Saturday night and Sunday, as a cold front drops out of Montana and brings some more typical December weather. However, the air is not terribly cold and with the lack of snow cover, temperatures will only fall back to near normal levels. The front could also bring some snow showers along and behind its passage. However, moisture is limited so any accumulations look minor. High pressure should then bring dry and more seasonable weather for early next week and possibly into the start of 2026. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 345 PM MST Wed Dec 24 2025 West of the Continental Divide...KJAC/KRKS/KPNA/KBPI Terminals Shortwave energy ejects northeast and crosses the state tonight ahead of a longwave trough off the US West Coast. This results in light rain becoming widespread at KJAC between 03Z-06Z/Thursday. Temperatures remain warm enough to keep light snow confined to the mountains with valley rain persisting. MVFR conditions prevail overnight at KJAC, while the potential for IFR lingers around 30 percent between 10Z-15Z/Thursday. The shortwave provides a period of lowered ceilings and the potential for MVFR at KBPI, KPNA, and KRKS between 13Z-17Z/Thursday. Conditions move to VFR at all terminals Thursday afternoon, although a cold pool aloft leads to instability showers in the vicinity of KJAC. Gusty south to southwest wind within the lowest 2k feet AGL leads to an increased likelihood of low-level wind shear late tonight at KJAC, KBPI, and KPNA. As the shortwave sweeps east, the LLWS potential diminishes between 13Z- 17Z/Thursday. Mountain tops obscured through 17Z/Thursday, with frequent mountain top obscurations to follow. East of the Continental Divide...KCPR/KCOD/KRIW/KLND/KWRL Terminals Mid/high-level cloud cover increases across the region tonight ahead of a longwave trough along the US West Coast. The main aviation hazard remains gusty surface south to southwest wind. Gusts 25-40kts persist at KCPR through the period, while other terminals generally see the wind increase by 04Z/Thursday as shortwave energy ejecting from the longwave trough tracks into the state. Downsloping southwest wind at KLND leads to low-level wind shear, especially after 06Z/Thursday until midday Thursday. Surface wind swings a bit more to the west and gusts 20-35kts Thursday afternoon in the wake of shortwave passage. Other than some lowered mid-cloud decks, conditions remain VFR at all terminals through the period. Mountain tops occasionally obscured 03Z-18Z/Thursday. Please see the Aviation Weather Center and/or CWSU ZLC and ZDV for the latest information on icing and turbulence forecasts. && .RIW WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from 11 PM this evening to 5 PM MST Thursday for WYZ012-014. High Wind Warning from 7 PM this evening to 11 AM MST Thursday for WYZ015-019-020-022. && UPDATE...Wittmann DISCUSSION...Hattings AVIATION...CNJ
Hazardous Weather Outlook National Weather Service Riverton WY 226 AM MST Wed Dec 24 2025 WYZ001>020-022>030-251400- Yellowstone National Park-Absaroka Mountains-Cody Foothills- North Bighorn Basin-Southwest Bighorn Basin-Southeast Bighorn Basin- Owl Creek and Bridger Mountains-Bighorn Mountains West- Bighorn Mountains Southeast-Northeast Johnson County- Southeast Johnson County-Teton and Gros Ventre Mountains- Jackson Hole-Wind River Mountains West-Wind River Mountains East- Upper Wind River Basin-Wind River Basin-Lander Foothills- Green Mountains and Rattlesnake Range- Natrona County Lower Elevations-Casper Mountain-Star Valley- Salt River and Wyoming Ranges-Upper Green River Basin Foothills- Upper Green River Basin-South Lincoln County- Rock Springs and Green River-Flaming Gorge-East Sweetwater County- 226 AM MST Wed Dec 24 2025 ...High Wind Warnings are in Effect from South Pass and Muddy Gap from this evening through Christmas morning... ...Winter Weather Advisories in effect for the Tetons and western Wind River Range from late this evening through Christmas afternoon... This Hazardous Weather Outlook is for Western and Central Wyoming. .DAY ONE...Today and Tonight. Tonight...High wind developing from South Pass and Muddy Gap through Casper. Please see High Wind Warning and forecasts for details. Snow spreading back into the western mountains. Please see forecasts and Winter Weather Advisories for details. .DAYS TWO THROUGH SEVEN...Christmas Day through Tuesday. Christmas Day...Snow continuing in the western mountains. Strong to high wind in central Wyoming, decreasing in the afternoon. Friday...Another chance of snow in the western mountains. Strong wind possible in central Wyoming once again. .SPOTTER INFORMATION STATEMENT... Weather spotters are encouraged to report significant weather conditions according to Standard Operating Procedures.
The national radar mosaic for the moment the first event began.
6 high wind. Local standard time, as filed.
High winds occurred in the wind prone portions of Natrona County. Some of the highest wind gusts included 82 mph at Scenic Drive, 76 mph on Outer Drive, and 74 mph along Hat Six Road.
Wind gusts of 70 to 75 mph were estimated on Casper Mountain, with one sensor on Casper Mountain Rd capturing a 73 mph gust.
A maximum wind gust of 93 mph occurred in Red Canyon along Highway 28.
Along Highway 28 near the Pathfinder Reservoir, 59 mph wind gusts were reported.
The Lander airport had a maximum wind gust of 60 mph.
A maximum wind gust of 66 mph occurred to the northeast of Buffalo, with 58 mph gusts at the Buffalo airport.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wyoming in 2025Every state in 2025This day in weather historyWarnings in Wyoming, December 2025
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1307771, 1309524, 1307769, 1307770, 1307773, 1307772.