A very tight west/east surface pressure gradient resulted in some high wind gusts across the western portions of the Billings Forecast Area.
Every event with a place to put it; 5 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 BYZ wrote it up.
A very tight west/east surface pressure gradient resulted in some high wind gusts across the western portions of the Billings Forecast Area.
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 Nov 30, 2:30 PM MST, 2 hours 5 minutes earlier.
Area Forecast Discussion
National Weather Service Billings MT
230 PM MST Tue Nov 30 2021
.DISCUSSION...
Tonight through Thursday night...
Unseasonably warm weather the next few days with strong mixing
across the region as a dampened upper level ridge shifts across
the area. Pressure gradients have already become tight enough
across the Continental Divide to support gap flow winds at
Livingston of 60 mph and these gradients continue to tighten the
next 24 hours with the gradients becoming more east west oriented.
This will allow the Harlowton to Big Timber area to begin
producing 60 mph winds tonight into Wednesday. Current wind
highlights look good and will make no changes.
Record high temperatures possible Wednesday and Thursday with
850mb temps approaching 15-16C which push readings into the upper
60s many areas. With a weak front passing over the area on
Thursday afternoon heating shuts off a little early so Wednesday
likely the warmer day. Winds will taper off Thursday afternoon
with the frontal passage. Dry through the period though airmass
moistens up a bit for a few mountain showers over the Bighorns
Thursday night.
Fire weather concerns have been mitigated for this event with the
rainfall Monday night enough across western zones to limit the
threat. borsum
Friday through Tuesday...
Friday is still looking like a more seasonal day following a cold
front. Temperatures will continue to remain mostly seasonal
through the period, but will warm a little going through the
weekend. The weekend looks to be dry, as guidance continues to
trend away from the wetter solutions. Winds along the western
foothills will again pickup Saturday into Sunday.
Early next week there continues to be a signal that the pattern
could be shifting, however, the consistency amongst the ensembles
so there is not much clarity on how this could evolve. Reimer
&&
.AVIATION...
VRF conditions expected today with winds being the primary
aviation hazard once again. Strong west to southwest winds will
develop from Livingston to Big Timber to Harlowton by early
afternoon, with gusts to 50kts expected. Elsewhere to 25kt are
possible through the early evening. Winds will stay strong along
the western foothills tonight. TWH/Reimer
&&
.PRELIMINARY POINT TEMP/POPS...
Wed Thu Fri Sat Sun Mon Tue
-----------------------------------------------------------
BIL 043/063 047/066 032/045 029/047 031/046 033/050 032/046
00/N 00/N 10/B 11/E 10/B 13/R 52/O
LVM 046/061 046/061 035/050 030/053 034/050 035/050 032/046
00/N 00/N 00/B 11/N 10/N 14/O 52/S
HDN 038/065 045/069 030/047 026/047 026/046 027/051 028/046
11/N 00/B 10/B 11/E 10/B 12/O 42/O
MLS 039/067 045/066 028/040 023/042 024/040 025/046 024/040
00/N 01/B 00/B 11/E 10/B 02/R 42/S
4BQ 041/068 045/068 032/044 026/046 028/044 028/049 029/044
00/N 00/B 00/B 11/B 10/B 01/E 32/O
BHK 037/064 041/064 026/039 021/041 023/038 023/044 021/038
00/N 00/B 00/B 11/B 10/B 01/E 31/B
SHR 037/070 043/071 033/049 026/052 029/047 027/052 029/046
00/U 00/B 11/B 11/B 10/B 12/R 43/O
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...High Wind Warning in effect until 11 AM MST Thursday FOR
ZONES 63-141-172-228.
Wind Advisory in effect until 11 AM MST Thursday FOR ZONES
65-66.
WY...None.
&&
weather.gov/billingsThe national radar mosaic for the moment the first event began.
5 high wind. Local standard time, as filed.
Winds gusted to 59 mph at the Big Timber Airport.
Winds gusted to 66 mph from Reed Point to Molt.
Winds gusted up to 61 mph across the area.
Winds gusted to 64 mph across the area.
Winds gusted to 64 mph across the area.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2021Every state in 2021This day in weather historyWarnings in Montana, November 2021
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: 987928, 987931, 987784, 988343, 987930.