An atmospheric river brought rain on top of deep snow cover resulting in an avalanche.
Every event with a place to put it; 1 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 MSO wrote it up.
An atmospheric river brought rain on top of deep snow cover resulting in an avalanche.
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 Missoula, MT wrote its last area forecast discussion before the first event at Feb 24, 2:47 AM PST, 6 hours 13 minutes earlier.
Area Forecast Discussion
National Weather Service Missoula MT
347 AM MST Mon Feb 24 2025
.DISCUSSION...
KEY MESSAGES:
- Mild temperatures will continue snowmelt runoff today, with a
slight risk for swollen small streams. Potential for ice jam
releases.
- Mountain snow and mixed precipitation tonight through Tuesday
night.
- Anomalously warm and drier end to the week. Highs could reach
the 50s.
Temperatures are expected to warm into the 40s and 50s today. With
the recent precipitation, there continues to be a threat for
swollen streams and ice jam releases.
High resolution models depict a squall line with moderate to heavy
precipitation moving across the region later this evening. With
falling snow levels, there could be a burst of heavy snow at
mountain passes with gusty winds between 30 and 40 mph. Persistent
snow showers above 3000 feet will continue on Tuesday, then shut
off by Tuesday night. Lookout and Lolo passes have the highest
snowfall range, from 6 to 12 inches for this system. Lost Trail
and Marias passes have a general 4 to 7 inch range for snowfall.
Valley roads could be initially wet, then slicken up by Tuesday
morning.
Models continue to depict a drier pattern for the second half of
the week through the first part of the weekend. Highs will be
above average. Morning fog will be possible.
&&
.AVIATION...Showers will wane by 15UTC(8am MST) this morning. A
squall line is expected to traverse from west to east between 8pm
MST this evening to 12am MST Tuesday. A heavy burst of snow, rain
or graupel, along with gusty winds over 30 knots are possible.
Showers will persist into Tuesday morning. Expect mountain
obscuration, especially along the Idaho/Montana border during this
time.
&&
.MSO WATCHES/WARNINGS/ADVISORIES...
MT...Flood Watch until 2 PM MST this afternoon for
Bitterroot/Sapphire Mountains...Butte/Blackfoot Region...
Flathead/Mission Valleys...Kootenai/Cabinet Region...Lower
Clark Fork Region...Missoula/Bitterroot Valleys...
Potomac/Seeley Lake Region...West Glacier Region.
Winter Weather Advisory until 8 AM MST this morning for
Bitterroot/Sapphire Mountains.
ID...Flood Watch until 1 PM PST this afternoon for Lower Hells
Canyon/Salmon River Region...Northern Clearwater
Mountains...Orofino/Grangeville Region...Southern
Clearwater Mountains.
Winter Weather Advisory until 8 AM MST this morning for Eastern
Lemhi County.
&&Preliminary Local Storm Report
National Weather Service Missoula MT
748 AM MST Mon Feb 24 2025
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0309 AM Non-Tstm Wnd Gst 6 WSW Trailcreek 48.88N 114.51W
02/24/2025 M71 MPH Flathead MT Mesonet
Mesonet station CYFM8 Hornet Mountain.
0510 AM Non-Tstm Wnd Gst 19 E Swan Lake 47.90N 113.44W
02/24/2025 M68 MPH Flathead MT Mesonet
Mesonet station TT727 Spotted Bear Lookout.
0100 AM Non-Tstm Wnd Gst 5 ENE Lonepine 47.72N 114.54W
02/24/2025 M67 MPH Lake MT Mesonet
Mesonet station MTM58 4.8 E Lonepine
(MT-MESO).
0300 AM Non-Tstm Wnd Gst 3 WSW Blacktail - Railr 48.26N 113.50W
02/24/2025 M67 MPH Flathead MT Mesonet
Mesonet station SNSLP 2.9 W Blacktail -
Railroad ID (GNP).
0300 AM Non-Tstm Wnd Gst 3 SW Pinnacle 48.32N 113.69W
02/24/2025 M65 MPH Flathead MT Mesonet
Mesonet station TRWMT Tunnel Ridge Wind.
0415 AM Non-Tstm Wnd Gst 3 S Clearwater 46.96N 113.37W
02/24/2025 M65 MPH Missoula MT Mesonet
Mesonet station MTM08 2.8 S Clearwater
(MT-MESO).
0300 AM Non-Tstm Wnd Gst 11 NE Stryker 48.76N 114.58W
02/24/2025 M63 MPH Flathead MT Mesonet
Mesonet station LKMMT Link Mountain.
0153 AM Non-Tstm Wnd Gst 2 ENE Stevensville 46.53N 114.05W
02/24/2025 M57 MPH Ravalli MT Mesonet
Mesonet station AV610 Stevensville.
1226 AM Non-Tstm Wnd Gst 5 SW Lolo 46.72N 114.16W
02/24/2025 M56 MPH Missoula MT Mesonet
Mesonet station MOMM8 Fire Effects Portable
No. 2.
1225 AM Non-Tstm Wnd Gst 2 WSW Deer Lodge 46.39N 112.76W
02/24/2025 M55 MPH Powell MT AWOS
AWOS station 38S9 1 WSW Deer Lodge.
0215 AM Non-Tstm Wnd Gst 6 E Lonepine 47.70N 114.51W
02/24/2025 M55 MPH Lake MT Mesonet
Mesonet station MTM57 5.7 E Lonepine
(MT-MESO).
0230 AM Non-Tstm Wnd Gst 3 N Moiese 47.42N 114.26W
02/24/2025 M53 MPH Lake MT Mesonet
Mesonet station MTM79 Mda Moiese N.
1008 AM Non-Tstm Wnd Gst 3 NW Pollock 45.34N 116.39W
02/23/2025 M52 MPH Idaho ID Mesonet
Mesonet station FW8176 Pollock.
0200 AM Non-Tstm Wnd Gst 6 N Whitefish 48.50N 114.34W
02/24/2025 M52 MPH Flathead MT Mesonet
Mesonet station BIGMS 6.3 N Whitefish (GNP).
0220 AM Non-Tstm Wnd Gst Moiese 47.37N 114.26W
02/24/2025 M51 MPH Lake MT Mesonet
Mesonet station MTM94 Cskt Bison Range.
0200 AM Non-Tstm Wnd Gst 2 SW Blacktail - Railro 48.26N 113.48W
02/24/2025 M50 MPH Flathead MT Mesonet
Mesonet station SH7MT Shed 7.
0855 AM Non-Tstm Wnd Gst 2 N Grangeville 45.95N 116.12W
02/23/2025 M49 MPH Idaho ID AWOS
AWOS station KGIC Grangeville.
0211 AM Non-Tstm Wnd Gst Hungry Horse 48.38N 114.06W
02/24/2025 M49 MPH Flathead MT Mesonet
Mesonet station HNYM8 Hungry Horse Raws.
1057 AM Non-Tstm Wnd Gst 4 NNW Opportunity 46.15N 112.87W
02/23/2025 M47 MPH Deer Lodge MT AWOS
AWOS station K3U3 3 NW Opportunity.
1215 AM Non-Tstm Wnd Gst 5 NW East Portal 47.45N 115.70W
02/24/2025 M47 MPH Mineral MT Mesonet
Mesonet station MTLPS 4.8 NW East Portal (MT
DOT).
0215 AM Non-Tstm Wnd Gst 1 WNW Plains 47.47N 114.90W
02/24/2025 M47 MPH Sanders MT AWOS
AWOS station KS34 Plains.
0712 AM Non-Tstm Wnd Gst Turah 46.84N 113.83W
02/24/2025 M46 MPH Missoula MT Mesonet
Mesonet station EW8564 East Bonner.
&&The national radar mosaic for the moment the first event began.
1 avalanche. Local standard time, as filed.
An avalanche blocked the eastbound lane of Highway 12 near Elk Summit Road and Powell Junction. The avalanche was estimated to be 8 feet tall and 30 feet long.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Idaho in 2025Every state in 2025This day in weather historyWarnings in Idaho, February 2025
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: 1237689.