An impressive winter storm system moved into north central Idaho and western Montana on the 22nd and continued to effect the region through the 24th. Initially a steady stream of Pacific moisture moved in from the west.
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 impressive winter storm system moved into north central Idaho and western Montana on the 22nd and continued to effect the region through the 24th. Initially a steady stream of Pacific moisture moved in from the west. This helped produce areas of heavy snowfall over the mountains and passes. The valleys received rain. As the main snowfall was ending a tight surface pressure gradient and a strong jet stream produced very strong winds.
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 22, 4:07 AM MST, 53 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
407 AM MST WED FEB 22 2012
...HIGH WINDS EXPECTED MANY AREAS OF WESTERN MONTANA TODAY...
...HEAVY MOUNTAIN SNOW AND BLOWING SNOW DEVELOPING LATER TODAY AND
CONTINUING INTO TONIGHT...
.DISCUSSION...A POWERFUL UPPER LEVEL JET STREAM AND SURFACE COLD
FRONT WILL BE SAGGING SOUTH ACROSS THE NORTHERN ROCKIES REGION
TODAY CREATING A VARIETY OF WEATHER IMPACTS. THE FIRST IMPACT
SHOWS STRONG WESTERLY WINDS ASSOCIATED WITH THE COLD FRONT. TIMING
OF THE FRONT HAS IT MOVING THROUGH NORTHWEST MONTANA THIS
MORNING...WEST-CENTRAL MONTANA AND NORTH-CENTRAL IDAHO THIS
AFTERNOON. THE GREATEST WIND IMPACT IS EXPECTED THIS AFTERNOON IN
WESTERN MONTANA AND LEMHI COUNTY. THE FRONT SHOULD PRODUCE
CONVECTIVE BANDS FORCING SOME OF THE VERY STRONG WINDS ALOFT TO
THE SURFACE.
ANOTHER IMPACT OF THE VIGOROUS COLD FRONT WILL BE THE LOWERING OF
THE SNOW LEVELS WITH THE PRODUCTION OF HEAVY MOUNTAIN SNOW. SNOW
LEVELS WILL INITIALLY EXIST AT OR ABOVE MOUNTAIN PASS LEVELS THIS
MORNING...LOWERING DRAMATICALLY TO THE VALLEY FLOOR BY LATE THIS
AFTERNOON. STRONG WINDS THROUGH THE MOUNTAIN PASSES OF WESTERN
MONTANA ALONG WITH THE BURST OF HEAVY SNOW WITH THE COLD FRONT
SHOULD PRODUCE NEAR WHITEOUT CONDITIONS AT TIMES.
BEHIND THE COLD FRONT...BREEZY CONDITIONS SHOULD CONTINUE WITH
FALLING TEMPERATURES TONIGHT. THE PRECIPITATION SHOULD BECOME
MORE SCATTERED. HOWEVER...THE ATMOSPHERE SHOULD SUPPORT A FEW SNOW
BANDS OVERNIGHT WITH LOCAL VALLEY ACCUMULATIONS POSSIBLE.
A NORTHWEST FLOW IS EXPECTED TO CONTINUE THURSDAY WITH SOME
GRADUAL DRYING OF THE AIR MASS. HOWEVER...LIGHT SNOW SHOWERS WILL
CONTINUE OVER THE MOUNTAINS THANKS TO OROGRAPHIC ENHANCEMENT.
FRIDAY THROUGH MONDAY...A SHORT DRYING PERIOD FOR WESTERN MONTANA
EARLY ON FRIDAY. BUT THE NEXT WEATHER SYSTEM WILL BE DIGGING DOWN
THE BRITISH COLUMBIA COAST AND MOVING INTO NORTHWEST MONTANA OVER
NIGHT...AND SPREAD PRECIPITATION ACROSS WESTERN MONTANA AND NORTH
CENTRAL IDAHO ON SATURDAY. IT LOOKS LIKE THE PRECIPITATION WILL BE
IN THE FORM OF RAIN MIXED WITH SNOW IN THE VALLEYS WITH SNOW OVER
THE PASSES AND HIGHER PEAKS. BY SUNDAY SOME COLDER AIR MOVES INTO
THE REGION...WITH HIGH AND LOW TEMPERATURES ABOUT 5 DEGREES BELOW
NORMAL. THIS WILL BE COLD ENOUGH TO CHANGE THE RAIN/SNOW MIX OVER
TO ALL SNOW. ON MONDAY THE LOW MOVES OFF TO THE SOUTHEAST WITH A
NORTHERLY FLOW SETTING UP INTO WESTERN MONTANA.
&&
.AVIATION...MAIN IMPACTS WILL BE THE POTENTIAL FOR STRONG WINDS
DEVELOPING AT ALL TERMINALS TODAY. ONCE THE FRONTAL BOUNDARY
PUSHES SOUTH THE WINDS SHOULD PICK UP IN EARNEST. THERE IS THE
POTENTIAL FOR STRONGER WINDS GUSTS TO 45 KT AT KGPI BETWEEN
22/1800Z AND 22/2000Z...TO 50 KT AT BOTH KMSO AND KBTM ESPECIALLY
BETWEEN 22/1800Z AND 22/2300Z AND TO 50 KT AT KSMN BETWEEN
22/2000Z AND 23/0300Z. MODERATE TO SEVERE TURBULENCE WILL BE
EXPECTED ACROSS MUCH OF THE NORTHERN ROCKIES. WITH THE UNSTABLE
ATMOSPHERE LATER THIS EVENING INTO THE OVERNIGHT THERE WILL BE
SNOW SHOWERS AROUND AND COULD BRING LOWER CEILINGS AND
VISIBILITIES THAN FORECAST. MOUNTAIN OBSCURATIONS ARE EXPECTED
THROUGH THURSDAY MORNING.
&&
.MSO WATCHES/WARNINGS/ADVISORIES...
MT... HIGH WIND WARNING UNTIL 5 PM MST THIS AFTERNOON BUTTE/BLACKFOOT
REGION.
WINTER STORM WARNING UNTIL 5 AM MST THURSDAY ABOVE 5000 FEET FOR
THE BITTERROOT/SAPPHIRE MOUNTAINS.
HIGH WIND WARNING UNTIL 5 PM MST THIS AFTERNOON
MISSOULA/BITTERROOT VALLEYS.
WINTER STORM WARNING UNTIL 5 AM MST THURSDAY FOR I-90 LOOKOUT
PASS TO HAUGAN.
HIGH WIND WARNING UNTIL 1 PM MST THIS AFTERNOON FLATHEAD/MISSION
VALLEYS.
WINTER STORM WARNING UNTIL 5 PM MST THIS AFTERNOON ABOVE 5000
FEET FOR THE WEST GLACIER REGION.
WIND ADVISORY UNTIL 1 PM MST THIS AFTERNOON KOOTENAI/CABINET
REGION.
HIGH WIND WARNING UNTIL 5 PM MST THIS AFTERNOON POTOMAC/SEELEY
LAKE REGION.
ID...WINTER STORM WARNING UNTIL 5 AM MST THURSDAY FOR LOST TRAIL PASS.
WIND ADVISORY UNTIL 11 PM MST THIS EVENING EASTERN LEMHI
COUNTY...WESTERN LEMHI COUNTY.
WINTER STORM WARNING UNTIL 4 AM PST THURSDAY ABOVE 5000 FEET FOR
THE SOUTHERN CLEARWATER MOUNTAINS.
WIND ADVISORY UNTIL 8 AM PST THIS MORNING FOR THE CAMAS PRAIRIE
AND HIGHWAY 95 BETWEEN WHITE BIRD AND RIGGINS.
&&
SHORT TERM...MSJ
LONG TERM....MSJ
AVIATION...NOBLEPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MISSOULA MT
1212 AM MST WED FEB 22 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0630 AM SNOW 1 WNW COLUMBIA FALLS 48.38N 114.20W
02/21/2012 M2.5 INCH FLATHEAD MT COCORAHS
24 HOUR SNOWFALL. 0.18 INCHES WATER EQUIVALENT.
0645 AM SNOW 3 ENE BIGFORK 48.08N 114.01W
02/21/2012 M3.3 INCH FLATHEAD MT COCORAHS
24 HOUR SNOWFALL. 0.22 INCHES WATER EQUIVALENT. SNOW
DEPTH WAS 7 INCHES.
0700 AM SNOW 1 SE MARION 48.10N 114.65W
02/21/2012 M1.1 INCH FLATHEAD MT COCORAHS
24 HOUR SNOWFALL. 0.04 INCHES WATER EQUIVALENT. SNOW
DEPTH WAS 13 INCHES.
0700 AM SNOW 4 NE RONAN 47.57N 114.04W
02/21/2012 M1.5 INCH LAKE MT COCORAHS
24 HOUR SNOWFALL. 0.10 INCHES WATER EQUIVALENT.
0730 AM SNOW 7 S COLUMBIA FALLS 48.27N 114.18W
02/21/2012 M2.5 INCH FLATHEAD MT COCORAHS
24 HOUR SNOWFALL. 0.19 INCHES WATER EQUIVALENT. SNOW
DEPTH WAS 7 INCHES.
0730 AM SNOW 28 SSW LIBBY 48.01N 115.79W
02/21/2012 M1.3 INCH SANDERS MT COCORAHS
24 HOUR SNOWFALL. 0.12 INCHES OF WATER EQUIVALENT. SNOW
DEPTH WAS 11 INCHES.
0800 AM HEAVY SNOW 3 NNW WOODLAND 46.35N 116.09W
02/21/2012 M6.1 INCH CLEARWATER ID COCORAHS
TOTAL STORM SNOWFALL. WATER EQUIVALENT WAS 0.46 INCHES.
0800 AM SNOW POWELL 46.58N 114.72W
02/21/2012 M4.3 INCH IDAHO ID CO-OP OBSERVER
24 HOUR SNOWFALL. 0.63 INCHES OF PRECIPITATION. SNOW
DEPTH WAS 37 INCHES. ELEVATION 3530 FT.
0800 AM SNOW PIERCE 46.49N 115.80W
02/21/2012 M3.0 INCH CLEARWATER ID CO-OP OBSERVER
24 HOUR SNOWFALL. 0.52 INCHES OF PRECIPITATION. ELEVATION
3185 FT.
0800 AM SNOW 3 SW OVANDO 46.99N 113.18W
02/21/2012 M1.5 INCH POWELL MT COCORAHS
24 HOUR SNOWFALL. 0.05 INCHES WATER EQUIVALENT. SNOW
DEPTH WAS 20 INCHES.
0800 AM SNOW 1 ESE WHITEFISH 48.41N 114.32W
02/21/2012 M3.5 INCH FLATHEAD MT COCORAHS
24 HOUR SNOWFALL. 0.28 INCHES OF WATER EQUIVALENT. SNOW
DEPTH WAS 13 INCHES.
0800 AM SNOW SWAN LAKE 47.93N 113.84W
02/21/2012 M4.1 INCH LAKE MT CO-OP OBSERVER
24 HOUR SNOWFALL. 0.20 INCHES OF PRECIPITATION. SNOW
DEPTH WAS 16 INCHES. ELEVATION 3270 FT.
0815 AM SNOW 1 WSW ROLLINS 47.90N 114.22W
02/21/2012 M2.0 INCH LAKE MT COCORAHS
24 HOUR SNOWFALL. 0.09 INCHES WATER EQUIVALENT.
1100 AM SNOW 14 NE SULA 45.98N 113.77W
02/21/2012 M2.0 INCH RAVALLI MT CO-OP OBSERVER
24 HOUR SNOWFALL. 0.13 INCHES OF PRECIPITATION. SNOW
DEPTH WAS 19 INCHES. ELEVATION 5160 FT.
0200 PM SNOW SEELEY LAKE 47.18N 113.48W
02/21/2012 M4.3 INCH MISSOULA MT CO-OP OBSERVER
24 HOUR SNOWFALL. 0.26 INCHES OF PRECIPITATION. SNOW
DEPTH WAS 23 INCHES. ELEVATION 4100 FT.
0200 PM SNOW TROUT CREEK 47.84N 115.60W
02/21/2012 M1.0 INCH SANDERS MT CO-OP OBSERVER
24 HOUR SNOWFALL. 0.30 INCHES OF PRECIPITATION. SNOW
DEPTH WAS 8 INCHES. ELEVATION 2356 FT.
1200 AM SNOW 6 NW MISSOULA 46.93N 114.08W
02/22/2012 M1.9 INCH MISSOULA MT OFFICIAL NWS OBS
TOTAL STORM SNOWFALL FOR THE PAST 48 HOURS. SNOW DEPTH
WAS 3 INCHES. LOCATION AT THE MISSOULA INTERNATIONAL
AIRPORT. ELEVATION OF 3199 FT.
0800 AM SNOW OLNEY 48.55N 114.58W
02/21/2012 M3.0 INCH FLATHEAD MT CO-OP OBSERVER
24 HOUR SNOWFALL. 0.42 INCHES OF PRECIPITATION. SNOW
DEPTH WAS 23 INCHES. ELEVATION 3165 FT.
&&
NOBLEThe national radar mosaic for the moment the first event began.
1 heavy snow. Local standard time, as filed.
The ski resort at Lost trail Pass reported a 24 hour snowfall of 36 inches.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Idaho in 2012Every state in 2012This day in weather historyWarnings in Idaho, February 2012
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: 366154.