After a heavy snow event across much of the forecast area, strong and gusty winds developed along the Rocky Mountain Front causing blowing snow and difficult driving conditions.
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.
After a heavy snow event across much of the forecast area, strong and gusty winds developed along the Rocky Mountain Front causing blowing snow and difficult driving conditions.
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 Nov 11, 10:50 PM MST, 10 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREAT FALLS MT 1050 PM MST SUN NOV 11 2012 .DISCUSSION... FURTHER UPDATE TO THE FORECAST THIS EVENING AS OF 935 PM MST. MAIN UPDATE THIS EVENING WAS TO ISSUE THE HIGH WIND WARNING FOR THE ROCKY MOUNTAIN FRONT. ALTHOUGH FORECAST MODELS DID NOT HAVE STRONG INDICATORS THAT HIGH WINDS WOULD DEFINITELY OCCUR UP THERE...OBSERVED WIND GUSTS ALONG THE ROCKY MOUNTAIN FRONT WERE GRADUALLY INCREASING INTO THE 40 TO 50 MPH RANGE THROUGHOUT THE EVENING. A MORE REMOTE LOCATION WAS REPORTING GUSTS IN EXCESS OF 60 MPH AS WELL...WHICH IS AN INDICATOR THAT STRONG WINDS IN MORE POPULATED AREAS WAS AT LEAST POSSIBLE. INITIAL MODEL FORECASTS ONLY HAD THE SMALL THREAT FOR STRONG WINDS FOR A BRIEF TIME OVERNIGHT...BUT THE LATEST FORECAST RUNS SEEM TO KEEP THIS MARGINAL STRONG WIND THREAT THROUGH THE DAY ON MONDAY...WHEN POTENTIAL MIXING WILL BE GREATER. HAVE THEREFORE DECIDED TO GO WITH THE HIGH WIND WARNING UNTIL 6 PM MST ON MONDAY. ONE ADDITIONAL CONCERN WAS THE POTENTIAL OF BLOWING AND DRIFTING SNOW DUE TO THESE STRONG WINDS OVER ALREADY SNOW PACKED AND ICY ROADS. SPEAKING OF BLOWING SNOW...AM GOING TO CONTINUE THE ADVISORY FOR BLOWING SNOW ELSEWHERE ACROSS MUCH NORTH CENTRAL AND CENTRAL MONTANA. THERE WAS LIKELY SOME CRUSTING OF SNOW TODAY...BUT MANY AREAS DID NOT MIX OUT AND WERE STILL QUITE COOL. THESE AREAS WILL LIKELY HAVE THESE GUSTY WINDS MIX DOWN OVERNIGHT AS THE SURFACE BOUNDARY MOVES EAST. THIS WILL ALSO MAKE OVERNIGHT LOWS FAIRLY TRICKY. AM EXPECTING MANY OF THESE LOCATIONS THAT ARE STILL IN THE COLD AIR TO MIX OUT OVERNIGHT...ALLOWING THEIR OVERNIGHT LOWS TO OCCUR AROUND OR SLIGHTLY AFTER MIDNIGHT BEFORE BEGINNING TO WARM. HAVE THEREFORE ATTEMPTED TO ADJUST OVERNIGHT LOWS ACCORDINGLY. COULSTON QUICK UPDATE THIS EVENING TO ADD MENTION OF SNOW SHOWERS ALONG THE ROCKY MOUNTAIN FRONT OVERNIGHT...ESPECIALLY UP TOWARDS GLACIER NATIONAL PARK...AS WEB CAMERAS SEEM TO INDICATE THAT THERE IS SNOW FALLING UP TO AND JUST OVER THE CONTINENTAL DIVIDE. COULSTON && .AVIATION... UPDATED 0550Z. MID AND HIGH LEVEL CLOUDS CONTINUE TO SLOWLY INCREASE AS THEY CROSS THE CONTINENTAL DIVIDE AHEAD OF A WEAK DISTURBANCE ALOFT THAT IS APPROACHING WESTERN MONTANA. SURFACE WINDS WILL REMAIN BREEZY ALONG THE ROCKY MOUNTAIN FRONT AND OVER THE ADJACENT PLAINS...CAUSING AREAS OF BLOWING SNOW. VFR CONDITIONS PREVAIL WITH ISOLATED AREAS OF MVFR DUE TO REDUCED VISIBILITIES FROM BLOWING SNOW. && .PREV DISCUSSION... /ISSUED 445 PM MST SUN NOV 11 2012/ TODAY THROUGH TUESDAY...AN UPPER LEVEL RIDGE BUILDS OVER THE NORTHERN ROCKIES TONIGHT BUT IS QUICKLY FLATTENED AS THE FLOW ALOFT TRANSITIONS BACK TOWARD A WESTERLY FLOW ALOFT ON MONDAY. SHORTWAVE ENERGY IN THIS ZONAL FLOW WILL BRING CLOUDS TO THE FORECAST AREA WITH SHOWERS OVER THE WESTERN MOUNTAINS. SOME SHOWERS WILL MAKE THEIR WAY OUT OVER THE PLAINS AND THE ISLAND RANGES OF CENTRAL MONTANA MONDAY NIGHT BUT WIDESPREAD ACCUMULATING SNOWS ARE NOT EXPECTED. MAIN IMPACT IN THE SHORT TERM CONTINUES TO BE THE POSSIBILITY OF BLOWING SNOW AS GUSTY WESTERLY WINDS PERSIST ALONG THE ROCKY MOUNTAIN FRONT AND OVER THE ADJACENT PLAINS. SO FAR ONLY MINOR AMOUNTS OF BLOWING SNOW HAVE BEEN OBSERVED BUT WILL ALLOW THE ADVISORY TO CONTINUE WITH THE STRONGEST WINDS EXPECTED OVERNIGHT. THOUGHT EARLIER THAT A HIGH WIND WARNING MIGHT BE NEEDED FOR THE NORTHERN ROCKY MOUNTAIN FRONT ...BUT AFTER LOOKING INTO DETAILS OF THE MID AND UPPER LEVEL WINDS ALONG WITH TEMPERATURE PROFILE AND PRESSURE GRADIENTS IT DOES NOT APPEAR THAT WIDESPREAD HIGH WINDS ARE LIKELY. BREEZY TO WINDY CONDITIONS WILL CONTINUE THROUGH THE FORECAST PERIOD IN NORTH CENTRAL MONTANA WHILE THE VALLEYS OF SOUTHWEST MONTANA WILL LIKELY REMAIN DECOUPLED FROM THE FLOW ALOFT. THIS WILL LEAD TO TEMPERATURES REMAINING A BIT COOLER IN THE SOUTHWEST WHILE THE PLAINS OF NORTH CENTRAL MONTANA TREND BACK TOWARD MORE SEASONABLE TEMPERATURES. MPJ TUESDAY NIGHT THROUGH SUNDAY...A FLAT UPPER LEVEL RIDGE WILL BE OVER THE ZONES TUESDAY NIGHT. SEVERAL WEAK DISTURBANCES WILL BE MOVING THROUGH THE FLOW ALOFT AND THE AIR MASS WILL REMAIN UNSETTLED. THESE UPPER LEVEL FEATURES WILL TIGHTEN THE SURFACE PRESSURE GRADIENT ALONG THE LEE OF THE ROCKIES...SO BRISK WINDS ARE EXPECTED ACROSS THE NORTHERN ROCKIES AND ADJACENT PLAINS. THE BEST CHANCE OF PRECIP WITH THESE DISTURBANCES WILL OVER THE WESTERN MOUNTAINS AND SOUTHWEST MONTANA. A HIGH PRESSURE RIDGE WILL BUILD WEDNESDAY NIGHT BUT ANOTHER DISTURBANCE WILL BE MOVING OVER THE PACIFIC NORTHWEST BY THURSDAY NIGHT. THIS WILL BRING MOISTURE AND PRECIP INTO THE ZONES...AND ONCE AGAIN THE BEST CHANCE FOR PRECIP WILL BE ACROSS SOUTHWEST MONTANA. THE SHORTWAVE WILL MOVE EAST OF THE REGION LATE FRIDAY OR FRIDAY NIGHT AND THE AIR MASS WILL DRY. THE NEXT WEATHER SYSTEM WILL BE OVER THE EASTERN PACIFIC BUT MOISTURE AHEAD OF THIS SYSTEM WILL REMAIN WEST OF THE ROCKIES THROUGH THE END OF THE PERIOD. THE SERIES OF DISTURBANCES THAT WILL MOVE THROUGH THE REGION WILL KEEP TEMPS RATHER MODERATE...NEAR OR SLIGHTLY ABOVE NORMALS THROUGH MOST OF THE PERIOD...BUT TEMPS WILL TREND UPWARDS BY LATE FRIDAY THROUGH SUNDAY AS THE HIGH PRESSURE ALOFT WARMS THE AIR MASS. ZELZER && .PRELIMINARY POINT TEMPS/POPS... GTF 16 38 28 40 / 0 0 20 10 CTB 16 36 25 39 / 10 10 10 10 HLN 8 33 21 40 / 0 10 20 20 BZN 2 30 18 39 / 0 10 20 10 WEY -3 24 9 30 / 0 20 40 20 DLN 4 29 17 36 / 0 10 30 20 HVR 1 31 19 35 / 0 0 10 0 LWT 10 36 25 39 / 0 0 20 0 && .TFX WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 6 PM MST MONDAY CASCADE... CHOUTEAU...EASTERN GLACIER...EASTERN PONDERA...EASTERN TETON... HILL...JUDITH BASIN...LIBERTY...NORTHERN ROCKY MOUNTAIN FRONT... SOUTHERN ROCKY MOUNTAIN FRONT...TOOLE. HIGH WIND WARNING UNTIL 6 PM MST MONDAY NORTHERN ROCKY MOUNTAIN FRONT...SOUTHERN ROCKY MOUNTAIN FRONT. && SHORT TERM...MPJ/COULSTON LONG TERM...ZELZER AVIATION...EMANUEL WEATHER.GOV/GREATFALLS
HAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE GREAT FALLS MT 256 PM MST SUN NOV 11 2012 MTZ009>013-044>046-048>050-121300- NORTHERN ROCKY MOUNTAIN FRONT-EASTERN GLACIER-HILL-CASCADE- CHOUTEAU-TOOLE-LIBERTY-EASTERN PONDERA- SOUTHERN ROCKY MOUNTAIN FRONT-EASTERN TETON-JUDITH BASIN- 256 PM MST SUN NOV 11 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL MONTANA AND NORTH CENTRAL MONTANA. .DAY ONE...THIS AFTERNOON AND TONIGHT A WINTER WEATHER ADVISORY FOR BLOWING SNOW IS IN EFFECT FOR MOST OF NORTH CENTRAL AND CENTRAL MONTANA. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY THE ADVISORY FOR BLOWING SNOW IS IN EFFECT UNTIL 6 PM MST MONDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. MTZ008-014-015-047-051>055-121300- BEAVERHEAD-CENTRAL AND SOUTHERN LEWIS AND CLARK-MADISON-BLAINE- FERGUS-JEFFERSON-BROADWATER-MEAGHER-GALLATIN- 256 PM MST SUN NOV 11 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL MONTANA...NORTH CENTRAL MONTANA AND SOUTHWEST MONTANA. .DAY ONE...THIS AFTERNOON AND TONIGHT THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.
1 high wind. Local standard time, as filed.
Trained Spotter in East Glacier Park estimated wind gusts up to 60 mph between 11pm November 11 and 1 am November 12.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2012Every state in 2012This day in weather historyWarnings in Montana, November 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: 418418.