A lingering artic air mass combined with persistent westerly gusty winds across the region to allow wind chill values to drop to -40 and below for portions of northeast Montana.
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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 GGW wrote it up.
A lingering artic air mass combined with persistent westerly gusty winds across the region to allow wind chill values to drop to -40 and below for portions of northeast Montana.
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 Glasgow, MT wrote its last area forecast discussion before the first event at Feb 7, 8:35 PM MST, 3 hours 25 minutes earlier.
Area Forecast Discussion...UPDATED National Weather Service GLASGOW MT 835 PM MST Tue Feb 7 2017 .SHORT TERM...for northeast Montana...tonight through Thu... An upper ridge to the west is generating a northwesterly flow aloft over Northeast Montana tonight, with very cold air continuing to flow into the area. The stationary frontal boundary between the Arctic air-mass and the warmer air to the southwest remains well to our south. There is a band of overrunning moisture that for the most part is sliding southeast through Central and Southeast Montana. This is spreading snow from LWT to BIL. Radar shows some light echoes flowing over southern areas of petroleum and Garfield Counties, but there are pops to cover that. The main threat tonight is the temperature. Winds are expected to remain light but slight breezes are producing wind chills to around 20 below, so will leave the Wind Chill Advisory in place, since lows tonight will fall into the teens below zero and even lower in places. Most grids grids look good so, except for adjusting too strong winds down, there very few edits needed. Templer Previous discussion - The weather system has exited of to the east early this morning. Moisture and weak instability will keep a few showers around this morning with most showers ending and drying conditions this afternoon. Another system tracking through the central Rockies later today and overnight is forecast to push some light snow up into portions of southern Petroleum and Garfield, accumulations will be fairly light. The main impact Wednesday morning and Thursday morning will be the hazardous wind chill values from -20 to -35 degrees below zero. High pressure moves out of Canada pushing most of the moisture to the south. However with cold air in place and northwest flow could get some light showers on Wednesday. High pressure drops southeast Wednesday night with an upper ridge building to the west. Chinook kicks in with very warm air spreading east of the divide. Warm front lifting across the state on Thursday with some moisture could produce a mixture of precipitation as the warm front moves east. TEC/Ebert .LONG TERM...Thu night through Tue... The extended forecast as described below for Thursday night into next weekend remains largely on track. The 12z model runs continue with exiting ridge with a largely amplified trough pushing across Montana extending south into southern California by Saturday. A little PVA may provide some forcing for ascent by Saturday night allowing for some shower activity though there is question as to whether it occurs just south of the CWA. If future guidance points to increased confidence, slight chance pops may become appropriate across the southern and western zones. Ensemble 500mb heights show increasing spread beyond the weekend making it difficult to time and track any shortwave features, though in general mild temperatures are expected with a building Pacific Ridge. When shortwaves flatten the ridge to push over the forecast area this will result in slightly cooler temperatures and precipitation chances. However, given the uncertainty will populate grids with latest consensus blends for now which maintains dry weather conditions at the moment. Maliawco Previous Long Term Forecast Discussion... Synoptic Setup: Long range begins with a long wave ridge over the middle third of the CONUS and Canada. the western third lies under southwest flow with a meso-ridge over southern British Columbia and southern Alberta. Behind this is a longwave trough developing off the coast of the Pacific Northwest stretching into the Gulf of Alaska, with yet another Pacific long wave ridge behind that. Thursday night through Friday: While the long wave ridge across the area exits, the meso ridge to the north and west will gain stronger influence and keep conditions dry through these periods with some mid to high clouds possible. Friday night through Saturday: long wave trough will move through the region and bring a slightly cooler pacific airmass with a little extra moisture. while temperatures may drop and moisture may go up , there is no where near enough temperatures differential to produce a significant snow storm... and will likely just have a dusting with any passage. Saturday Night onward: Models point toward the Pacific ridge progressing right in behind this trough and warming conditions back up again with downslope chinook being a possible outcome. The size of the ridge means that this warmer, dry pattern will likely persist through mid-week. GAH && .AVIATION... General VFR conditions are expected to prevail across terminals tonight amid some mid-level ceilings. Clearing is in the cards from north to south across the region for Wednesday. Northwest winds around 10 kts will become west at 10 to 20 kts by Wednesday afternoon. Maliawco/Mickelson && .GLASGOW WATCHES/WARNINGS/ADVISORIES... Wind Chill Advisory until 1 PM MST Wednesday for Central and Southeast Phillips...Central and Southern Valley...Daniels... Dawson...Eastern Roosevelt...Garfield...McCone...Northern Phillips...Northern Valley...Petroleum...Prairie...Richland... Sheridan...Southwest Phillips...Western Roosevelt...Wibaux. && weather.gov/glasgow
Hazardous Weather Outlook National Weather Service GLASGOW MT 226 PM MST Tue Feb 7 2017 MTZ016>027-059>062-081200- Central and Southeast Phillips-Central and Southern Valley-Daniels- Sheridan-Western Roosevelt-Petroleum-Garfield-McCone-Richland- Dawson-Prairie-Wibaux-Northern Phillips-Southwest Phillips- Northern Valley-Eastern Roosevelt- 226 PM MST Tue Feb 7 2017 This Hazardous Weather Outlook is for portions of northeast Montana. * Potential Impacts: Bitter Cold Wind Chills and Cold Temperatures. * Timing: Tonight through early Wednesday afternoon and possibly again overnight Wednesday into Thursday morning * Wind: Northwest 10 to 15 mph with gusts up to 20 mph. * Wind Chills: From -20 to -40 below. * Temperatures: 25 below to 5 below zero with some sheltered areas falling to around 30 below zero. * Location: All of NE Montana tonight to early Wednesday afternoon, and Thursday morning for Valley, portions of McCone, Richland, all of Roosevelt, Daniels, and Sheridan counties PRECAUTIONARY/PREPAREDNESS ACTIONS... A Hazardous Weather Outlook is issued when hazardous weather could impact the region within the next week. Be sure to stay tuned for future updates as locations, timing, and impacts could change. Begin preparations to mitigate any impacts that could result from the hazardous weather. &&
The national radar mosaic for the moment the first event began.
2 cold/wind chill. Local standard time, as filed.
Wind chill values near -40 and colder were recorded at the Comertown Turn-Off MT-5 DOT site through the overnight and morning hours.
Wind chill values near -40 and colder were recorded at the Navajo MT-5 DOT site through the early morning hours.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2017Every state in 2017This day in weather historyWarnings in Montana, February 2017
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: 669462, 669463.