Upper level shortwave energy moves over the region with a Canadian cold front sweeping southward through Montana. Widespread snow and areas of blowing snow develop from northwest to southeast through the morning hours.
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.
Upper level shortwave energy moves over the region with a Canadian cold front sweeping southward through Montana. Widespread snow and areas of blowing snow develop from northwest to southeast through the morning hours.
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 29, 10:55 PM MST, 2 hours 10 minutes earlier.
Area Forecast Discussion National Weather Service Great Falls MT 1055 PM MST Sat Dec 29 2018 ...UPDATED AVIATION SECTION... .SYNOPSIS... Strong and gusty winds continue tonight. A strong Canadian cold front moves southeast through Montana Sunday, bringing accumulating snow and blowing snow to much of the region. Very cold temperatures will persist into Monday before warmer and windy conditions return by the middle of the week. && .UPDATE... Minor updates to the forecast in the short term tonight to reduce POP over Central Montana until the morning. Still looking like strong winds through the night with cold frontal passage coming down through Central Montana around mid morning. && .AVIATION... Updated 0555Z. VFR conditions will gradually worsen to MVFR in clouds, snow, and blowing snow with mountain obscuration from the northwest around 12Z along the Hi-Line through 20Z in southwest Montana. Periods of IFR conditions will then be likely between 15Z and 00Z, especially across north central and central Montana. A passing Canadian cold front will trigger these conditions as it shifts the strong and gusty westerly winds to lighter but still gusty northerly winds. Mountain wave turbulence and low level wind shear will remain a concern mainly through 18Z. Coulston && .PREV DISCUSSION... /ISSUED 500 PM MST Sat Dec 29 2018/ Wind gusts along the Rocky Mountain Front have exceeded 90mph today as a powerful weather system develops over the Northern Rockies. Surface pressure falls are exceeding 2 mb/hr as the lee- side trough deepens over Southern Alberta. Scattered areas of rain or mountain snow have developed amid the moist westerly flow aloft. Most of the precipitation today has been associated with warm advection aloft and an embedded upper level disturbance. Wind gusts will remain strong overnight, but will begin to trend lower after peaking late this afternoon and evening. Precipitation intensity increases over the Northern Rockies tonight, where a winter storm warning is in effect for impacts associated with the combination of heavy snow and blowing snow. Travel over Marias Pass will become extremely difficult, to near impossible through early Sunday, with temporary whiteout conditions possible. A strong cold front arrives early Sunday, and advances across the forecast area from north to south. Although this does shut down the strong west winds, the frontal passage will produce areas of snow with a switch to northerly winds. Temperatures will fall through the day on Sunday across North-central MT as colder air moves in. The most difficult travel conditions will be encountered over mountain passes. However, most locations will see at least light snow. With falling temperatures, roads are expected to become icy, with some potential for flash freeze, or rapid development of icy conditions on area roadways. Winter weather advisories are posted to cover these winter weather impacts. Snowfall begins to dissipate Sunday night into Monday morning. There remains some uncertainty regarding the ending time for snowfall, so some of these advisories may need to be extended a bit on Monday morning. Temperatures on Monday will become quite cold, ranging from single digits below zero overnight, to the teens during the day Monday. PN New Years Day through Saturday...A major short wave trough moves eastward, out of the area, as a ridge of higher heights approaches from the west and becomes the dominant weather driving feature for the Treasure State. Colder temperatures are replaced with warmer highs, once again, and subsidence and drying prevail. Wednesday, the major short wave ridge begins to flatten, and an upper level disturbance will allow for precipitation to fall along the Continental Divide. As the ridge flattens, the flow takes on a more westerly component. Thursday, a North Pacific Low approaches the west coast of British Columbia and North America, pressing up against the ridge and resulting in a tightening gradient and strong cross barrier flow. Additionally, this system will advect moisture into the area, allowing for more precipitation along the Continental Divide through Friday. Gusty winds continue through Friday, as well, with the passage of the major short wave trof. Saturday, expect a decrease in wind speeds as well as a decrease in temperatures as highs and lows return to more seasonable ranges for this time of year. - Fogleman && .PRELIMINARY POINT TEMPS/POPS... GTF 30 34 5 16 / 30 80 80 10 CTB 25 29 3 19 / 50 70 30 0 HLN 30 31 7 18 / 60 70 80 0 BZN 26 33 4 15 / 40 70 60 0 WEY 4 23 -8 11 / 100 100 40 10 DLN 23 30 3 16 / 30 70 50 0 HVR 28 33 1 13 / 40 70 50 0 LWT 29 33 0 10 / 40 100 70 20 && .TFX WATCHES/WARNINGS/ADVISORIES... High Wind Warning until 8 AM MST Sunday Blaine...Cascade... Central and Southern Lewis and Clark...Chouteau...Fergus... Hill...Judith Basin...Liberty. Winter Weather Advisory from 2 AM to 11 PM MST Sunday Broadwater...Central and Southern Lewis and Clark...Jefferson. Winter Weather Advisory from 5 AM Sunday to 2 AM MST Monday Chouteau...Eastern Glacier...Eastern Pondera...Eastern Teton... Fergus...Liberty...Toole. Winter Weather Advisory from 2 AM to 11 PM MST Sunday Beaverhead...Gallatin...Madison. Winter Weather Advisory from 11 PM this evening to 9 AM MST Monday Cascade...Judith Basin...Meagher. High Wind Warning until 8 AM MST Sunday Eastern Glacier... Eastern Pondera...Eastern Teton...Toole. Winter Storm Warning until 11 PM MST Sunday Northern Rocky Mountain Front...Southern Rocky Mountain Front. High Wind Warning until 8 AM MST Sunday Northern Rocky Mountain Front...Southern Rocky Mountain Front. && http://www.weather.gov/greatfalls
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
858 PM MST SAT DEC 29 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0802 PM NON-TSTM WND GST 11 S CHINOOK 48.43N 109.23W
12/29/2018 M69 MPH BLAINE MT PUBLIC
&&PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1230 AM MST SUN DEC 30 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1130 PM NON-TSTM WND GST 5 ESE PENDROY 48.04N 112.20W
12/29/2018 M70 MPH TETON MT MESONET
MESONET STATION RICMT, RICE RIDGE - 4 E
PENDROY.
&&
SAC1 high wind. Local standard time, as filed.
High wind gust of 57 mph measured at mesonet station mtpnd, pendroy mdt.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2018Every state in 2018This day in weather historyWarnings in Montana, December 2018
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: 797065.