A low pressure system off the Pacific coast caused a tightening pressure gradient that allowed strong winds aloft to mix down to the surface across much of Central Montana.
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 low pressure system off the Pacific coast caused a tightening pressure gradient that allowed strong winds aloft to mix down to the surface across much of Central 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 Great Falls, MT wrote its last area forecast discussion before the first event at Jan 15, 4:35 AM MST, 1 hour 25 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREAT FALLS MT 435 AM MST Thu Jan 15 2015 Updated Aviation .DISCUSSION...Today through Saturday Evening. The center of the high pressure ridge that worked its way through WA/OR yesterday has now reached western MT and is expected to make steady progress through the state today. The passing ridge will bring mostly clear skies across the central and southwest counties through this evening, along with high temperatures in the upper 30s to mid 40s for most of the region, though the Helena Valley and a few far southwest valleys will remain in the upper 20s to around 30 degrees. Not much change in model solutions for past several runs in their depiction of shortwave trof closely following the ridge as it exits into the Dakotas late tonight. Moisture associated with the trof will bring some scattered areas of light snow, mostly to the higher elevations of the Rocky Mtn Front and some of the southwest mtn ranges. The most notable model change was a northward shift in the path of the jet stream, now projected come across more of central MT on Fri. With the resulting increase in coverage of 60 mph winds in the mid- and low-levels mainly north of a Helena-to-Great Falls line, have expanded the earlier high wind watch to now include the western Hiline and extending south to Cascade and southern Lewis & Clark counties. Winds in the added area likely will begin later than along the Rocky Mtn Front and last into mid-Friday evening. A surface cold front will push across our region Fri night as the trof heads into eastern MT. The drying effects of the gusty downslope winds will limit precipitation development through the central counties, but can't rule out some isolated rain/snow showers as the front sweeps south. Will also be monitoring conditions for spotty areas of freezing rain, though current model soundings generally indicate a low probability of occurrence. Precipitation will dissipate quickly during the Fri overnight hours and dry conditions are forecast for Sat. The cold front will bring a temporary break in the warming trend as high temps on Sat drop back into the mid- and upper 30s. Waranauskas Saturday Night through Thursday...Progressive westerly flow aloft coupled with embedded shortwaves and ample Pacific moisture will keep unsettled weather over the Northern Rockies through the weekend and early next week. Accumulating snow will be likely in the mountains at and above pass level while windy conditions are expected along and areas adjacent to the Rocky Mountain Front. Forecast confidence is moderate to high regarding accumulating mountain snow and gusty winds along the Rocky Mountain Front and high wind and winter weather highlights may be needed. Snow amounts Saturday night through Sunday Night will be 2 to 4 inches at pass level with locally higher amounts above pass level. Snow levels will be around 5000 feet so have kept a slight chance of rain and snow across the plains/valleys. There is also the potential for high winds greater than 58 mph along the Rocky Mountain Front and adjacent plains Saturday night through Sunday evening as a strong Pacific cold front moves across the region. Will continue to monitor for possible high wind highlights. Highs on Sunday will be well above seasonal averages. Early next week, the overall flow aloft will shift northwesterly, which will allow for cooler air to move into the area as well as keep off and on chances for light snow. There is still uncertainty regarding precipitation chances and snow amounts, but at this time any snow accumulations should be light. Drier conditions are expected by the middle of next week as a ridge of high pressure begins to build over the Western U.S., though temperatures will remain near to slightly below seasonal averages. MLV && .AVIATION... UPDATED 1200Z. Fog has returned to the Helena Valley overnight with periods of MVFR/IFR conditions through 15z. Fog may also affect KBZN this morning with brief periods of MVFR conditions possible. Elsewhere, VFR conditions will prevail through the forecast period with increasing mid- and high-level clouds this afternoon. Strong westerly flow aloft will result in gusty downslope winds and increased mountain wave activity along the Rocky Mountain Front and adjacent plains, including KCTB and KGTF where wind gusts of 30 to 40 kts are possible. Downslope winds will continue to strengthen on Friday. Some mountain obscuration is possible by this evening. MLV && .PRELIMINARY POINT TEMPS/POPS... GTF 44 33 44 25 / 0 10 10 20 CTB 39 26 40 23 / 0 10 10 20 HLN 30 21 38 23 / 0 10 10 20 BZN 33 19 37 18 / 0 10 20 20 WEY 28 16 29 11 / 0 20 20 30 DLN 37 25 39 19 / 0 20 20 20 HVR 39 26 43 25 / 0 10 10 20 LWT 47 30 44 24 / 0 10 10 20 && .TFX WATCHES/WARNINGS/ADVISORIES... HIGH WIND WATCH from Friday morning through Friday evening Cascade...Central and Southern Lewis and Clark...Eastern Glacier...Eastern Pondera...Eastern Teton...Liberty...Toole. HIGH WIND WATCH from late tonight through Friday afternoon Northern Rocky Mountain Front...Southern Rocky Mountain Front. && weather.gov/greatfalls www.twitter.com/NWSGreatFalls www.facebook.com/NWSGreatFalls
18 high wind. Local standard time, as filed.
High sustained winds, measured at 38KT (43MPH), were reported 1 mi E of East Glacier Park, MT at the Two Medicine Bridge DOT sensor.
High sustained winds, measured at 35KT (40MPH), were reported 4 mi NNE of McAllister, MT at the Norris Hill DOT sensor.
High sustained winds, measured at 39KT (44MPH), were reported at the Sunburst, MT sensor.
High wind gusts, measured at 50KT (58MPH), were reported 13 mi W of Bynum, MT at the Dellwo sensor.
High wind gusts, measured at 54KT (62MPH), were reported 3 mi SW of Cut Bank, MT at the Cut Bank airport ASOS.
High wind gusts, measured at 52KT (60MPH), were reported 3 mi WNW of Raynesford, MT.
High wind gusts, measured at 53KT (61MPH), were reported 8 mi SW of Wolf Creek, MT at the Sieben Flats DOT sensor.
High sustained winds, measured at 35KT (40MPH), were reported 4 mi NNE of McAllister, MT at the Norris Hill DOT sensor.
High wind gusts, measured at 72KT (83MPH), were reported 1 mi E of East Glacier Park, MT at the Two Medicine Bridge DOT sensor.
High wind gusts, measured at 74KT (85MPH), were reported 13 mi W of Bynum, MT at the Dellwo sensor.
High wind gusts, measured at 52KT (60MPH), were reported 13 mi W of Bynum, MT at the Dellwo sensor.
High sustained winds, measured at 36KT (41MPH), were reported 3 mi SW of Cut Bank, MT at the Cut Bank airport ASOS.
High sustained winds, measured at 35KT (40MPH), were reported at the Sunburst, MT sensor.
High wind gusts, measured at 50KT (58MPH), were reported 20 mi N of Rudyard, MT.
High wind gusts, measured at 52KT (60MPH), were reported 17 mi W of Pendroy, MT.
High wind gusts, estimated at 52KT (60MPH), were reported 4 mi S of Cascade, MT.
High wind gusts, measured at 55KT (63MPH), were reported 10 mi S of Chinook, MT.
High wind gusts, measured at 54KT (62MPH), were reported 1 mi E of East Glacier Park, MT at the Two Medicine Bridge DOT sensor.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2015Every state in 2015This day in weather historyWarnings in Montana, January 2015
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: 552745, 552746, 552748, 552747, 552749, 552750, 552751, 552752, 552753, 552764, 552769, 552755, 552758, 552756, 552754, 552760, 552761, 552772.