More strong winds occurred across the area, producing gusts up to 85 mph (mainly 55-65 mph elsewhere).
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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 BYZ wrote it up.
More strong winds occurred across the area, producing gusts up to 85 mph (mainly 55-65 mph elsewhere).
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 Billings, MT wrote its last area forecast discussion before the first event at Dec 18, 3:56 PM MST, 5 hours 4 minutes earlier. Its key messages:
Area Forecast Discussion
National Weather Service Billings MT
356 PM MST Thu Dec 18 2025
.KEY MESSAGES...
- Mountain wave activity could bring strong, erratic, and
potentially damaging wind gusts to the mountains and foothills
this evening into Friday.
- Another period of strong gap winds is expected over the western
foothills this evening into Friday.
- Small chance of light freezing rain in far eastern Montana early
Friday morning (15 percent chance or less).
- Cold front Friday afternoon and evening ends strong wind threat
and brings a band of precipitation (rain transitioning to snow)
through the area. Impacts to Friday evening commute possible.
- Periods of moderate to heavy snowfall over the Absaroka-
Beartooth Mountains today into Saturday. Generally 1 to 2 feet
of snow forecast, greatest on south and west aspects.
&&
.DISCUSSION...
Today through Wednesday...
Another period of strong winds is expected over the mountains and
foothills this evening into Friday ahead of a cold front passage.
With this, both gap and mountain wave winds are forecast. This
could bring strong and potentially damaging winds to all area
mountains and foothills. If you live along the foothills or have
travel/recreation plans along the mountains and foothills this
evening into Friday, make sure to be prepared for another round of
strong winds.
As far as the gap winds go, look for winds to increase around
Livingston to Nye first before spreading out towards the Highway
191 corridor this evening into tonight. With this, the strongest
winds are expected to occur around Livingston to Nye where gusts
of 60 to 75 mph are forecast. Around Big Timber to Melville, winds
look to be a bit weaker, but still strong with gusts of 50 to 65
mph. As you go north through Harlowton to Judith Gap, the pressure
gradient favoring the Livingston to Nye and Big Timber to
Melville winds looks less impressive, but mid-level winds up to 65
knots with warming temperatures tonight behind a warm front
passage should allow strong winds with gusts up to 60 mph to occur
at some point in this area. As far as timing of the strongest
winds go, generally tonight through Friday morning is the most
likely time to see the strongest gusts. Around Harlowton, there
may be two peaks, one in the early morning Friday and one as a
cold front moves into the area early in the afternoon. The High
Wind Warnings for Livingston to Nye and Big Timber to Melville
remain in good shape, and the High Wind Watch for the Wheatland
and Judith Gap zones has been upgraded to a High Wind Warning.
As far as the mountain wave winds go, both the Beartooth and
Bighorn/Pryor foothills are in danger of seeing mountain wave
activity tonight. Latest guidance suggests the Beartooth foothills
from Nye through Red Lodge could see mountain wave gusts begin
late this evening, potentially peaking early Friday morning. Over
the Bighorn/Pryor foothills out towards Sheridan and Interstate
90, the mountain wave activity could be delayed a bit, potentially
beginning tonight and peaking during the morning hours Friday.
With this, erratic wind gusts of 50 to 65 mph are forecast along
the foothills of both mountains ranges, with locally higher gusts
possible along the immediate foothills (20 percent chance of a 70
mph wind gust). With this, the High Wind Watches for the foothills
of the Beartooths and Bighorn/Pryor Mountains have been upgraded
to High Wind Warnings. The Bighorn and Pryor Mountains have also
been added into the High Wind Warnings to account for the strong
winds expected along their north and east facing slopes.
While no high winds are expected over the plains of southern
Montana and northern Wyoming Friday, south-westerly wind gusts of
25 to 45 mph look to spread north behind a warm front passage
tonight, strongest over south-central Montana.
A cold front passage Friday afternoon and evening will end the
strong wind threat across the area and will bring a band of
rain/snow transitioning to all snow through the area. While this
band looks to be pretty fast moving, impacts to the Friday evening
commute are possible, especially along the southern foothills
where upslope enhancement may allow snow to linger into the night.
Additionally, good frontogenesis combined with some instability
may allow for pockets of moderate to heavy snow to develop during
the evening hours...something to watch. By late Friday night, the
snow looks to come to an end across the lower elevations. As far
as snowfall amounts go, most of the area will only see a dusting
to a couple tenths of an inch. However, the foothills along the
Beartooth front (including Red Lodge), could see 1 to 4 inches of
snow with this event. Around and just north of the Bighorn and
Pryor Mountains, 1 to 3 inches of snow is possible as well.
While the chance remains low (15 percent or less), there may be a
short period of light freezing rain over far eastern Montana
early Friday morning as the warm front lifts through the area. At
this time, impacts look to remain minimal, but it is another
thing to watch.
Over the Absaroka-Beartooth Mountains, the Winter Storm Warning
in effect through early Saturday morning remains in good shape as
1 to 2 feet of snow, mainly on west and south facing slopes, is
forecast. Winds gusting as high as 75 mph could also result in
widespread blowing snow impacts.
Mainly zonal flow will continue through the weekend and into the
first part of next week. Pacific moisture will continue streaming
into the region at times bringing mountain snowfall. Arends
.AVIATION...
WSW winds will increase across the western foothills this
afternoon/evening, with gusts 45-65 knots into Friday morning. The
strongest gusts are forecast around KLVM.
There is increased concern for mountain wave development tonight.
Potentially impacted terminals include KRED and KSHR, with wind
gusts of approaching or exceeding 50 knots. Moderate to strong
LLWS will also impact all terminals in the region, late tonight
through Friday morning. Mountains will remain partially to fully
obscured through the period. Matos
&&
.PRELIMINARY POINT TEMP/POPS...
Fri Sat Sun Mon Tue Wed Thu
-----------------------------------------------------------
BIL 034/057 026/042 026/043 033/053 030/049 030/052 028/044
16/W 50/U 01/E 13/W 21/B 11/B 21/B
LVM 038/051 021/037 021/044 036/050 032/050 036/052 031/047
39/W 50/N 02/W 45/W 32/W 23/W 32/W
HDN 031/057 022/042 020/043 029/051 027/047 027/051 024/042
16/W 70/U 00/B 12/W 10/B 01/B 21/B
MLS 024/048 017/034 018/039 028/046 026/043 026/043 023/039
23/W 20/U 00/B 01/E 10/E 00/B 21/B
4BQ 028/055 023/038 021/042 031/053 029/047 030/053 028/045
14/W 60/U 00/B 01/B 10/B 00/B 11/B
BHK 016/048 013/031 015/041 025/047 024/041 023/045 021/040
22/W 20/U 00/U 00/E 10/B 00/B 11/B
SHR 028/057 017/037 016/043 028/053 026/051 029/054 026/045
17/W 91/U 00/B 01/B 00/B 00/B 11/B
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...High Wind Warning in effect from 8 PM this evening to 2 PM
MST Friday FOR ZONES 56-138-141-169-171-172.
High Wind Warning in effect from 11 PM this evening to 5 PM
MST Friday FOR ZONES 63-228.
High Wind Warning in effect until 2 PM MST Friday FOR ZONES
65-66.
Winter Storm Warning in effect until 5 AM MST Saturday FOR
ZONE 67.
WY...High Wind Warning in effect from 8 PM this evening to 2 PM
MST Friday FOR ZONES 198-199.
&&
weather.gov/billingsThe national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
Power outages occurred in Story, WY due to strong winds. Adjacent weather stations reported gusts in the 60s to low 70s.
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: 1308151.