The first of two pushes of strong westerly winds developed along the Rocky Mountain Front and adjacent plains Feb 6 into the 7th.
Every event with a place to put it; 10 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 TFX wrote it up.
The first of two pushes of strong westerly winds developed along the Rocky Mountain Front and adjacent plains Feb 6 into the 7th.
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 Feb 6, 10:04 AM MST, 3 hours 25 minutes earlier.
Area Forecast Discussion National Weather Service Great Falls MT 1004 AM MST Mon Feb 6 2023 .SYNOPSIS... An approaching weather system will continue to bring accumulating mountain snow to Central and Southwest Montana this morning, with around 2 to 5 inches expected over Raynolds, Targhee, Bozeman, Deep Creek, and Kings Hill Passes. Attention then turns to increasing westerly winds across the plains of Central and North Central Montana from Monday night into Tuesday, with high winds expected along the Rocky Mountain Front and adjacent plains. && .UPDATE... Snow has dissipated across most of Southwestern Montana this morning, with just a few leftover snow showers over the higher terrain. With this in mind, we have cancelled the Winter Weather Advisory a little bit earlier than originally anticipated. Ludwig && .AVIATION... 1004 AM MST Mon Feb 6 2023 (06/18Z TAF Period) Low to mid-level cloudiness will persist over Southwest and Central Montana throughout the TAF period as Pacific moisture streams eastward and across the Northern Rockies. This will bring low VFR/MVFR conditions to the KBZN and KEKS terminals through the 06/21z to 07/03Z timeframe, thereafter CIGS will gradually improve to VFR/low VFR. Mountains will be obscured throughout the entire 0618/0718 TAF period, especially along the Continental Divide. Increasing low to mid-level west winds will also bring strong and gusty surface winds to the valleys and plains of Central and North Central Montana from the late afternoon/early evening hours through Tuesday morning. Mountain wave activity, potentially very strong immediately downwind of the Rocky Mountain Front, will become increasingly likely between 07/00z and 07/15z. Additionally, instance of low-level wind shear will also be possible over this timeframe at the terminals across the North Central Montana plains. Refer to weather.gov/zlc for more detailed regional aviation weather and hazard information. && .PREV DISCUSSION... /ISSUED 352 AM MST Mon Feb 6 2023/ This Morning... No changes were made to the existing Winter Weather Advisory for the mountains of southwest and central Montana. Snow will gradually diminish during the late morning hours over this area, though light snow will continue along the Northern Rockies including Marias Pass with light snow accumulations. This Afternoon through Tuesday... Transient ridging over the Northern Rockies today will quickly be flattened out by an approaching shortwave trough this evening, with zonal flow then expected over the Northern Rockies through Tuesday afternoon. This flattening of the upper level ridge combined with increasing cross barrier flow and a strengthening surface pressure gradient along the Rocky Mountain Front will lead to increasing southwest to west surface winds from Monday afternoon and through the morning hours on Tuesday over the plains of Central and North Central Montana. SPC HREF ensemble max wind gust guidance depicts wind gusts pushing right up to, but perhaps not quite reaching, the 60-mph gust threshold for a High Wind Warning over north- central Montana especially on the eastern slopes of the mountain ranges. However, strongest surface winds will be across the Eastern Glacier Park Region, Southern Rocky Mountain Front, Northern and Southern High Plains, and Eastern Glacier/Western Toole/Central Ponder Counties. These gusty winds will be further enhanced beneath mountain wave activity, with latest BUFKIT sounding data supporting a very favorable environment (i.e. ridgetop stability) for mountain waves to develop and propagate eastward over the plains. Current NBM probabilistic data supports a 75-85% chance for wind gusts of 48kts or higher at St Mary, Gleason, and Cut Bank, with a 90-100% chance for 48kts or higher at Browning and Dellwo through Tuesday morning. Even more impressive is the probability for sustained winds of 34kts or higher at Cut Bank and Browning from Monday afternoon/evening through Tuesday morning, which is between a 70-90% chance. Given the strong deterministic and probabilistic support for high winds through Tuesday morning for the Eastern Glacier Park Region, Southern Rocky Mountain Front, Northern and Southern High Plains, and Eastern Glacier/Western Toole/Central Pondera Counties, the High Wind Warning continues from 21z Monday/01z Tuesday through 17z Tuesday. Despite another potential High Wind event Tuesday evening, decided it was best for the High Wind Warning to expire at 17z Tuesday given a 12hr window of sub- warning level wind speeds across the warned area. -CC/Moldan Tuesday night through next weekend... The aforementioned trough responsible for increased winds across the region Monday and Tuesday will continue its approach Tuesday night, crossing over the region Wednesday. Much like the system expected across the region today, most precipitation is expected to be reserved for terrain, and looks to be relatively light in nature at this time for most areas except along the immediate Continental Divide across the Glacier Park region. The probability for snow in excess of 6 inches is around 65-70% across Marias Pass from Tuesday evening through Wednesday. The probability for snow in excess of 4 inches across the highest peaks of Southwest Montana is running generally below 50% over the same time period, except along the Continental Divide toward Chief Joseph Pass where there is ~80% probability. The second impact from this system is expected to be another round of stronger westerly winds across the plains Wednesday morning. A brief period of lower wind speeds is expected across the plains Tuesday evening before a surface trough begins to redevelop in lee of terrain late Tuesday night. Probabilities for gusts in excess of 55 mph that are greater than 50% reside along the immediate eastern slopes of the Rocky Mountain Front and into the Cut Bank area. This time period is also included in the current High Wind Watch in effect along the Rocky Mountain Front. Cooler temperatures are expected to filter into the region Wednesday evening and overnight, especially across Southwest Montana, with some models indicating upslope snow over the mountains and adjacent northwest-facing slopes Wednesday afternoon into Wednesday night. From Thursday through next weekend, ensemble clusters generally agree in upper ridging Thursday gradually transitioning to weak upper troughing by the end of next weekend. Generally mild temperatures for mid-February are expected during this time, with over half of the ensemble clusters generally dry or with light precipitation. However, about 35-45% of the ensemble clusters do bring some precipitation primarily to the western and southwestern Montana mountain regions for at least a part of next weekend. && .PRELIMINARY POINT TEMPS/POPS... GTF 45 34 45 32 / 10 0 0 10 CTB 41 33 43 29 / 0 0 0 10 HLN 40 30 43 28 / 10 0 0 50 BZN 35 18 38 20 / 30 0 0 50 WYS 31 10 27 12 / 40 10 0 70 DLN 35 20 36 19 / 10 0 0 40 HVR 37 28 41 28 / 10 0 0 10 LWT 39 28 44 28 / 40 0 0 10 && .TFX WATCHES/WARNINGS/ADVISORIES... High Wind Warning from 2 PM this afternoon to 10 AM MST Tuesday for East Glacier Park Region-Northern High Plains-Southern High Plains-Southern Rocky Mountain Front. High Wind Watch from Tuesday evening through Wednesday afternoon for East Glacier Park Region-Eastern Glacier, Western Toole, and Central Pondera-Northern High Plains-Southern High Plains- Southern Rocky Mountain Front. High Wind Warning from 6 PM this evening to 10 AM MST Tuesday for Eastern Glacier, Western Toole, and Central Pondera. && http://www.weather.gov/greatfalls
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1222 PM MST MON FEB 6 2023
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0734 AM NON-TSTM WND GST 1 SSE CHRISTINA 47.37N 109.31W
02/04/2023 M59 MPH FERGUS MT MESONET
MEASURED AT KMTHILGE5.
&&
HARTThe national radar mosaic for the moment the first event began.
10 high wind. Local standard time, as filed.
Mesonet station tr276 L-C portable No. 1 measured multiple gusts in excess of 58 mph, including a gust of 89 mph.
An Ambient Weather station in northern Glacier county measured a gust of 59 mph.
Mesonet station fw8512 measured a gust of 62 mph.
Mesonet station DELMT Dellwo measured two gusts in excess of 58 mph, including a 70 mph gust.
Mesonet station MTBWG measured multiple wind gusts in excess of 58 mph, including a 71 mph gust.
ASOS station KCTB Cut Bank Airport measured a 60 mph gust.
An Ambient Weather station (Cut Bank Resort) measured a gust of 68 mph.
An Ambient Weather station in Cut Bank measured a gust of 66 mph.
Mesonet station KTMBYNUM11 measured a gust of 63 mph, very near the Southern Rocky Mountain Front.
The RAWS near Browning (BGRM8) measured a gust of 60 mph.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2023Every state in 2023This day in weather historyWarnings in Montana, February 2023
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: 1071770, 1071758, 1071775, 1073942, 1071753, 1073938, 1073939, 1073940, 1073943, 1073941.