A robust upper trough, embedded waves, and jet energy supported two rounds of snow across North-central and Southwest Montana October 25-27, 2023. The first round, Oct 25 & 26, was more impactful to North-central and Central Montana, while the second round of snow, Oct 26 & 27, was more impactful to Southwest through Central Montana.

Winter Storm in EAST GLACIER PARK REGION, MONTANA
From 24-OCT-23 03:00:00 to 25-OCT-23 10:30:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported 10 inches of total snow on bridges from the event. Additionally, snotel equipment at Many Glacier estimated 10 inches storm total snow. Most snow at the snotel site fell in the morning through afternoon on the 24th.

Winter Storm in SOUTHERN ROCKY MOUNTAIN FRONT, MONTANA
From 24-OCT-23 11:00:00 to 25-OCT-23 16:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

Snotel equipment at Copper Camp observed the long duration snow event. Through 10AM MDT Wednesday the 25th, 9 inches new snow was estimated. Thereafter, an additional 6 inches of snow fell, totaling 15 inches for the entire event.

Winter Storm in CASCADE COUNTY BELOW 5000FT, MONTANA
From 24-OCT-23 18:00:00 to 25-OCT-23 19:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Numerous reports of snow reaching winter storm criteria as well as impacts from the snow were received over this period. Official NWS obs at WFO Great Falls totaled 6 inches new snow for the event. Both an NWS employee and the public reported snowfall amounts in excess of 8 inches around Great Falls. NWS employees on their way in to work saw two jack-knifed semis on Interstate 15 blocking an exit ramp.

Winter Storm in BEARS PAW MOUNTAINS AND SOUTHERN BLAINE, MONTANA
From 24-OCT-23 20:30:00 to 25-OCT-23 15:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported 10 inches new snow between Tuesday evening and Wednesday afternoon near Hays. Time of reaching impact criteria is estimated. Additionally, law enforcement reported a multi vehicle wreck due to slick roads that resulted in the closure of MT Highway 66 near Hays.

Winter Storm in EASTERN PONDERA AND EASTERN TETON, MONTANA
From 24-OCT-23 19:00:00 to 25-OCT-23 14:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

Several cocorahs volunteer reports and public reports were received of 6 inches storm total snow in the Fairfield and Dutton areas by the morning of 10/25. Additionally, law enforcement reported several slide offs in the Conrad area, where 4 to 5 inches of snow was estimated to have fallen.

Heavy Snow in HELENA VALLEY, MONTANA
From 25-OCT-23 23:30:00 to 26-OCT-23 14:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Several reports were received of an additional 6 inches of snow in the Helena valley overnight the 25th into the 26th. Most snow fell between midnight and 6 AM in Helena. Official NWS observations at the Helena Airport totaled 6.4 inches late evening the 25th through the early afternoon on the 26th.

Heavy Snow in MEAGHER COUNTY VALLEYS, MONTANA
From 24-OCT-23 17:00:00 to 25-OCT-23 10:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter in White Sulphur Springs reported 12 inches new snow between 6PM 10/24 and 11AM 10/25.

Heavy Snow in FERGUS COUNTY BELOW 4500FT, MONTANA
From 24-OCT-23 17:00:00 to 26-OCT-23 16:30:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Multiple trained spotters, coop reports, as well as public reports were received for the lower elevations of Fergus county that met winter storm criteria. Reports ranged from up to 13 inches in Lewistown to 12 inches near Hilger, to 15 inches in Grass Range.

Heavy Snow in UPPER BLACKFOOT AND MACDONALD PASS, MONTANA
From 24-OCT-23 21:00:00 to 26-OCT-23 17:35:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Only one report was received in total for this zone. The report came from the public near Marysville, who reported 24 inches storm total snow accumulation. The time of meting criteria is estimated.

Heavy Snow in GATES OF THE MOUNTAINS, MONTANA
From 24-OCT-23 17:00:00 to 25-OCT-23 17:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Two reports were received that met winter storm criteria in the Gates of the Mountains area. The first was from an NWS employee 6 miles NE of Craig, who measured 9.2 inches storm total snow. Additionally, a coop observer at Holter Dam measured 9 inches new snow for the event.

Heavy Snow in LITTLE BELT AND HIGHWOOD MOUNTAINS, MONTANA
From 24-OCT-23 20:00:00 to 26-OCT-23 16:47:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

Three reports of storm total snow of 9 inches or greater were received for the Little Belts. The first report was from SNOTEL equipment at Spur Park, which estimated 9 inches storm total snow. There were two additional public reports, one from Neihart and another from Showdown Montana near Porphyry peak. The storm total reports were 11 and 14 inches respectively.

Heavy Snow in MISSOURI HEADWATERS, MONTANA
From 24-OCT-23 20:00:00 to 25-OCT-23 08:15:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reports 7.5 inches new snow 14 miles north northeast of Cardwell along MT-69 by 915 AM 10/25. Start time estimated.

Winter Storm in MISSOURI HEADWATERS, MONTANA
From 25-OCT-23 20:00:00 to 26-OCT-23 14:15:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Law enforcement reported one serious injury from a wreck along Interstate 90 near mile marker 262. Law enforcement determined that slick roads from winter weather contributed to the vehicle crash. Additionally, there was a public report of 6 inches new snow 15 miles north of Cardwell along MT-69 between 9 PM 10/25 and 312 PM 10/26.

Heavy Snow in MADISON RIVER VALLEY, MONTANA
From 25-OCT-23 19:30:00 to 26-OCT-23 09:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

A co-op observer in Ennis reported 6.7 inches of new snow by 9AM 10/26. Additionally, the public reported 8 inches new snow 12 miles south of Ennis by 10 AM MDT 10/26.

Heavy Snow in BEAVERHEAD AND WESTERN MADISON BELOW 6000FT, MONTANA
From 25-OCT-23 21:00:00 to 26-OCT-23 09:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Multiple reports were received in this zone in excess of 6 inches. A co-op observer 1 mile ENE of Sheridan measured 8 inches new snow between 11 PM MDT 10/25 and 7 AM MDT 10/26. Additionally, multiple reports (Trained spotter and public) were received of greater than 6 inches accumulation in Dillon, with the highest total received being 8 inches.

Winter Storm in SOUTHERN HIGH PLAINS, MONTANA
From 24-OCT-23 14:00:00 to 25-OCT-23 13:36:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

A coop observer as well as USFS personnel reported snow accumulations in excess of 6 inches. The coop observer, 4 miles sse of Bynum, measured 6.5 inches new snow by 630 AM MST 10/25. USFS estimated 12 inches new snow in the Augusta area through the early afternoon 10/25.

Winter Storm in WESTERN AND CENTRAL CHOUTEAU COUNTY, MONTANA
From 24-OCT-23 15:40:00 to 25-OCT-23 12:45:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Social media report of 6 inches total snow in Fort Benton. Start and end of event are estimated.

Winter Storm in JUDITH BASIN COUNTY AND JUDITH GAP, MONTANA
From 24-OCT-23 18:00:00 to 26-OCT-23 15:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Multiple public reports, trained spotter reports, and an emergency manager reported snowfall totals in excess of 9 inches with this storm. Reports in excess of 9 inches came from Raynesford, the Stanford area, and Hobson The peak amount was measured in Stanford, where 15 inches of storm total snow was measured.

Heavy Snow in SNOWY AND JUDITH MOUNTAINS, MONTANA
From 24-OCT-23 19:00:00 to 26-OCT-23 16:25:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

SNOTEL equipment at Crystal Lake estimated 9 inches new snow by 8 AM the 25th. Snow continued into the late afternoon on the 26th.

Winter Storm in HELENA VALLEY, MONTANA
From 24-OCT-23 18:35:00 to 25-OCT-23 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Many reports were received from the Helena Valley meeting winter storm criteria. Reports ranged from 6 inches all the way up to 13.4 inches in the Helena area. Official NWS obs at the Helena Airport measured 6.5 inches storm total snow.

Winter Storm in ELKHORN AND BOULDER MOUNTAINS, MONTANA
From 24-OCT-23 18:30:00 to 25-OCT-23 16:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Many sources reported a combination of heavy snow and snow/ice damage, including law enforcement, trained spotters, Snotels, and the public. Multiple wrecks were reported on Homestake Pass by la enforcement the morning of 10/25. Many reports of 9 inches total were received from Montana City, Jefferson City, and Clancy, with a peak snow report of 24 inches in Jefferson City.

Heavy Snow in CANYON FERRY AREA, MONTANA
From 24-OCT-23 19:00:00 to 25-OCT-23 10:30:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter reported 12 inches of snow by 10/25 at 8 AM MDT along US-287 in far northwestern Broadwater county. Additionally, the public reported 8 inches of snow in Toston by midday 10/25.

Heavy Snow in GALLATIN AND MADISON COUNTY MOUNTAINS AND CENTENNIAL MOUNTAINS, MONTANA
From 24-OCT-23 22:00:00 to 26-OCT-23 06:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: SNOTEL

Snotels Carrot Basin, Black Bear, Madison Plateau, and Lower Twin all reported 9 inches of snow or more, with the highest total from Black Bear along the Idaho border (17 inches total).