A strong pressure gradient across the Madison River Valley resulted in high sustained winds at two locations, including the Ennis Airport and Norris Hill.
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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 TFX wrote it up.
A strong pressure gradient across the Madison River Valley resulted in high sustained winds at two locations, including the Ennis Airport and Norris Hill.
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 Great Falls, MT wrote its last area forecast discussion before the first event at Dec 10, 9:55 AM MST, 3 hours 27 minutes earlier.
Area Forecast Discussion National Weather Service Great Falls MT 955 AM MST Sat Dec 10 2022 ...Aviation Section Updated... .SYNOPSIS... This afternoon and into tomorrow, snow falls across The Great Divide, as well as portions of southwest Montana. Otherwise, today remains mainly dry for most of the region. Sunday afternoon, precipitation becomes more widespread from north central to southwest Montana, and by Monday, high temperatures generally range in the teens, yet again. && .UPDATE... Updated forecast is out. Just minor adjustments to the forecast towards current trends this morning. Lowered afternoon temperatures a few degrees in the Havre/Bozeman areas. Also, increased winds a touch over Southwest MT, with some gusts over 50 mph already. Main concern is snowfall potential as we go from Sunday into Monday. There is a possibility that winter highlights might be needed for portions of the region from Sunday into Monday. Brusda && .AVIATION... 955 AM MST Sat Dec 10 2022 (10/12Z TAF period) Strong and gusty south winds will continue through 00-06z this evening across portions of the Northern Rockies, particularly in the north-south orientated valleys across Southwest Montana (i.e. KEKS terminal) where frequent wind gusts of 40-50kts are expected. These strong winds may lead to blowing snow and instances of reduced VIS to as low as 4SM at the KEKS terminals. Snow is also expected to overspread Southwest Montana and the Continental Divide over much of the TAF period, possibly reaching as far north as a KDLN to KEKS line by 06z tonight and a KHLN to KLWT line by 12z Sunday. Confidence in snow impacting the KEKS, KBZN, KHLN, and KLWT terminals prior to 18z Sunday remains low. VFR conditions are expected throughout the TAF period; however, mountains will be obscured along the Continental Divide and across Southwest Montana. - Moldan Refer to weather.gov/zlc for more detailed regional aviation weather and hazard information. && .PREV DISCUSSION... /ISSUED 453 AM MST Sat Dec 10 2022/ Today through Sunday morning...An upper level ridge moves eastward across the region, with an upper level trof approaching from the west. Divergence aloft is located within the transition between ridge and trof. Surface low pressure resides upstream, and a surface high moves southeastward through the area. Generally, southerly surface winds are forecast for southwest Montana in the area of interface between high and low pressure. Expect a dry day for most of the area. Moisture enters southwest Montana in association with the eastward moving upstream trof, while the attendant surface low enters the region, and snow showers begin over portions of southwest Montana. The greatest impacts are expected over Monida Pass, Targhee Pass, Raynolds Pass and the West Yellowstone area. Two to four inches of snow are forecast at pass level over a 24 hour period from this afternoon and continuing into Sunday. Localized areas may receive higher amounts. Lower elevations are expected to receive a trace to less than an inch of snow. Additionally, considering the forecast southerly winds for southwest Montana, gusty winds are forecast. Visibility is expected to be reduced, at times, in snow and blowing snow. Sunday afternoon through Thursday morning...With the continued approach of the deepening North Pacific upper level trof, southwest Montana receives little to no break as moisture continues to be advected into the area, becoming widespread across central and north central Montana, as well. Temperatures take a dive, with low elevation highs, generally, ranging from the teens to the low 20s. Snowfall continues through the beginning of the week, with conditions beginning to improve from west northwest to east southeast from Monday evening through Tuesday. During this period, the probability of snowfall greater than 2 inches, generally, ranges from 70% to 85% region wide. The chance of snowfall greater than 4 inches is likely (55% to 65%) across portions of central and southwest Montana. As the upper level closed low begins to track northeastward, The Treasure State experiences more snowfall courtesy of this system's wrap around moisture. Wednesday, snowfall becomes widespread across north central, central and parts of southwest Montana, yet again, with conditions improving from west to east into Thursday. Thursday afternoon through next Saturday...Numerical model guidance solutions are quite divergent, at this point; therefore, confidence is low in the forecast for this period. Low elevation high temperatures remain in the teens to low 20s through Friday with dry conditions Thursday afternoon through Friday. The coldest overnight lows are expected to occur during the early morning hours of Friday, when lows are expected to fall in the single digits below zero across much of the area. The Hi-Line area is expected to see the coldest low elevation overnight lows. Saturday, temperatures warm, just a bit, with highs generally ranging from the teens to mid 20s. As of this point, it appears that the next trof may enter the area by Saturday, when there is a slight chance of snowfall. - Fogleman && .PRELIMINARY POINT TEMPS/POPS... GTF 34 21 31 9 / 0 0 50 80 CTB 24 10 23 7 / 0 0 60 70 HLN 34 22 33 12 / 0 0 30 80 BZN 29 17 34 13 / 0 0 20 70 WYS 29 14 32 13 / 20 40 90 80 DLN 31 21 33 16 / 0 10 50 70 HVR 24 8 25 10 / 0 0 20 70 LWT 30 21 37 10 / 0 0 20 60 && .TFX WATCHES/WARNINGS/ADVISORIES... None. && http://www.weather.gov/greatfalls
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1046 AM MST SAT DEC 10 2022
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1007 AM NON-TSTM WND GST 5 E GALLATIN GATEWAY 45.58N 111.10W
12/10/2022 M46 MPH GALLATIN MT MESONET
MESONET STATION FW1650 BOZEMAN.
&&
MOLDANPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1047 AM MST SAT DEC 10 2022
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0759 AM NON-TSTM WND GST 4 NE LIMA 44.69N 112.54W
12/10/2022 M57 MPH BEAVERHEAD MT MESONET
MESONET STATION LMRM8 ANTELOPE RAWS.
&&
MOLDANPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1255 PM MST SAT DEC 10 2022
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1100 AM NON-TSTM WND GST 16 SE GALLATIN GATEWAY 45.44N 110.95W
12/10/2022 M66 MPH GALLATIN MT MESONET
MESONET STATION GNFHY 10.7 W EMIGRANT
(AVALANCHE).
&&
MOLDANPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1256 PM MST SAT DEC 10 2022
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1242 PM NON-TSTM WND GST 4 NNE MCALLISTER 45.50N 111.70W
12/10/2022 M55 MPH MADISON MT MESONET
MESONET STATION MTNOR NORRIS HILL (MT DOT).
&&
MOLDANThe national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
Two sensors measured sustained winds of 40 mph or more, including the MTDOT sensor at Norris Hill and AWOS station KEKS Ennis Airport.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2022Every state in 2022This day in weather historyWarnings in Montana, December 2022
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: 1071706.