A Pacific storm system brought cold and snow to portions of the Rocky Mountain front. Snow amounts in excess of 8 inches were reported.
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.
A Pacific storm system brought cold and snow to portions of the Rocky Mountain front. Snow amounts in excess of 8 inches were reported.
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, 10:30 PM MST, 5 hours 27 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREAT FALLS MT 1030 PM MST FRI NOV 11 2011 UPDATED AVIATION SECTION .UPDATE... SATELLITE/RADAR IMAGERY THIS EVENING SHOWS A VIGOROUS SHORTWAVE TROUGH AND ASSOCIATED COLD FRONT OVER CENTRAL WA...POISED TO SWEEP EAST ACROSS THE NORTHERN ROCKIES AND MT LATER TONIGHT THROUGH SATURDAY MORNING. EXPECT THE SURFACE COLD FRONT TO REACH THE WESTERN MOUNTAINS LATE TONIGHT OR EARLY SATURDAY MORNING WITH THE FRONT QUICKLY PROGRESSING EAST ACROSS CENTRAL AND SW MT SATURDAY MORNING. SNOW WILL INCREASE OVER THE MTNS OF THE ROCKY MTN FRONT FIRST WITH THE APPROACH OF THE FRONT WITH SNOW ALSO DEVELOPING AROUND OR SHORTLY AFTER MIDNIGHT OVER THE SW MT MTNS IN MOIST SW FLOW ALOFT AIDED BY STRONG DYNAMICS AHEAD OF THE UPPER LEVEL SYSTEM. BAND OF FRONTAL PRECIP...CURRENTLY SEEN EXTENDING FROM THE ID PANHANDLE SW INTO CENTRAL OREGON WILL DROP SE WITH THE FRONT...MOVING THROUGH CENTRAL AND SW MT SATURDAY MORNING. THIS WILL MAINLY IMPACT PORTIONS OF THE FORECAST AREA SOUTH AND EAST FROM HELENA WITH INSTABILITY ALONG THE FRONT POTENTIALLY BRINGING A BRIEF PERIOD OF MODERATE SNOW AND ACCUMULATIONS AROUND AN INCH OR LESS FOR MOST VALLEY LOCATIONS. IN THE MOUNTAINS HOWEVER...LIFT AHEAD OF AND BEHIND THE FRONT WILL BE FOCUSED FOR A LONGER PERIOD WITH SNOW CONTINUING MODERATE AT TIMES THROUGH SATURDAY MORNING BEFORE ENDING. EXPECT HIGHEST ACCUMULATIONS NEAR THE ID AND WY BORDERS INCLUDING W-YELLOWSTONE...BIG SKY AND PASSES INTO ID WHERE WINDS WILL ALSO BE SIGNIFICANT...ESPECIALLY AT THE TIME OF FRONTAL PASSAGE AND HAVE INCLUDED THESE AREAS IN A WINTER WX ADVISORY THROUGH SATURDAY MORNING. HOENISCH && .AVIATION... UPDATED 0530Z. A COLD FRONT HAS PASSED THROUGH NORTHWEST PORTIONS EAST OF THE CONTINENTAL DIVIDE AND WILL SPREAD SOUTHEAST THE REST OF TONIGHT AND EARLY SATURDAY MORNING. THE EFFECTS OF THE FRONT WILL BE FELT MOST OVER SOUTHWEST MONTANA. STILL FEEL CONFIDENT THAT FRONTAL PASSAGE WILL BE WITHIN AN HOUR OF THE FORECAST TIMES AT KHLN (09Z) AND KBZN (13Z). OVER SOUTHWEST MONTANA EXPECT A PERIOD OF SNOW AFTER THE FRONTAL PASSAGE WITH AT LEAST OCCASIONAL MVFR CONDITIONS IF NOT PREDOMINANTLY MVFR CONDITIONS. IN THE SNOW EXPECT LOCAL IFR CEILINGS AND VISIBILITIES. AREAS OF MOUNTAIN OBSCUREMENT HAVE DEVELOPED OVER THE ROCKY MOUNTAIN FRONT AND WILL SPREAD TO SOUTHWEST MONTANA LATE TONIGHT AND EARLY SATURDAY MORNING. FRONTAL PASSAGE OVER THE PLAINS SHOULD ONLY RESULT IN A MINOR VEERING OF THE WINDS AND CEILINGS WILL STAY VFR. SATURDAY MORNING INTO THE AFTERNOON EXPECT SCATTERED SNOW SHOWERS TO DEVELOP OVER THE PLAINS. SNOW WILL DIMINISH TO SCATTERED SNOW SHOWERS OVER SOUTHWEST MONTANA DURING THE AFTERNOON. EXPECT LOCAL MVFR OR POSSIBLY EVEN IFR CEILINGS AND VISIBILITIES IN THESE SNOW SHOWERS. THESE LOWER CONDITIONS ARE NOT EXPECTED TO LAST MORE THAN AN HOUR. GUSTY WEST WINDS ARE DIMINISHING OVER THE ROCKY MOUNTAIN FRONT. EXPECT LOCAL WIND GUSTS NEAR 50 KNOTS OVER THE HIGHER TERRAIN OF SOUTHWEST MONTANA LATE TONIGHT AND EARLY SATURDAY MORNING ASSOCIATED WITH THE COLD FRONT. BLANK && .PREV DISCUSSION... /ISSUED 500 PM MST FRI NOV 11 2011/ TONIGHT THROUGH SUNDAY...A PAIR OF FORECAST PROBLEMS TODAY. FIRST...HIGH WINDS WILL CONTINUE INTO THE NIGHT...AND SECOND...AN APPROACHING LOW PRESSURE TROF AND THE RESULTING SNOW. A SHORTWAVE WILL DROP OVER THE PACIFIC NORTHWEST FRIDAY NIGHT AND MOVE OVER THE ROCKIES SATURDAY MORNING. MOISTURE AHEAD OF THIS SYSTEM WILL BE INCREASING OVER THE ROCKIES THIS EVENING...AND MOVE INTO THE SOUTHWEST ZONES AROUND MIDNIGHT. MOVEMENT WILL BE QUICK AND HEIGHTS WILL BE BUILDING ALOFT AGAIN BY AFTERNOON. STRONG...NORTHWEST FLOW ALOFT WILL KEEP THE AIRMASS COOL AND UNSETTLED AFTER TROF PASSAGE. GOOD DYNAMICS ARE ASSOCIATED WITH THIS TROF. HOWEVER...THE QUICK MOVEMENT WILL LIMIT THE TIME FOR SNOW ACCUMULATION AND BEST LIFT WILL BE WEST OF THE DIVIDE AND SOUTH OF THE ZONES DURING THE NIGHT. ALSO OF CONCERN...STRONG WINDS ACROSS THE ROCKIES WILL BE CONTINUING AS THE SNOW MOVES INTO THE AREA. 6-10 INCHES ARE POSSIBLE TONIGHT THROUGH SATURDAY CLOSE TO THE DIVIDE. MID LEVEL WEST WINDS 45+ KTS SHOULD BE PRESENT AT THE BASE OF THE TROF. THUS...RESTRICTED VISIBILITIES AND OTHER TRAVEL HAZARDS ARE EXPECTED TO DEVELOP. WEATHER WILL BE MENTIONED IN THE HIGH WIND WARNING THROUGH THE NIGHT AND HANDLED AFTERWARD BY THE CURRENT WINTER WEATHER ADVISORY. A COLD FRONT ASSOCIATED WITH THE TROF WILL PUSH QUICKLY THROUGH THE ZONES. HOWEVER...A SECOND PERIOD OF SNOW ACROSS THE PLAINS IS POSSIBLE AS A SECONDARY COLD FRONT SLIDES ACROSS THE CANADIAN BORDER AND BRINGS COOL AND MOIST AIR ACROSS THE CENTRAL AND EASTERN ZONES SATURDAY AFTERNOON. THE FLOW ALOFT WILL REMAIN FAIRLY UNSETTLED THROUGH SUNDAY AND WITH MOISTURE ACROSS THE ROCKIES AND SOUTHWEST ZONES...LIGHT SNOW WILL CONTINUE INTO SUNDAY. ZELZER SUNDAY NIGHT THROUGH FRIDAY...THE MEDIUM RANGE PERIOD CONTINUES TO LOOK UNSETTLED AND COOL. AN UPPER CLOSED LOW SINKING SOUTHEAST ACROSS SASKATCHEWAN ON MONDAY WILL BACKDOOR A SURFACE COLD FRONT AND SCATTERED SNOW ACROSS THE AREA. HEIGHTS RISE ON TUESDAY BUT CONTINUED UNSTABLE NORTHWEST FLOW ALOFT WILL KEEP ISOLATED SNOW IN THE FORECAST. THE FLOW ALOFT ON WEDNESDAY BECOMES MORE ZONAL BUT WEAK SHORT WAVE ENERGY EMBEDDED WITHIN THIS FLOW WILL ALLOW FOR ISOLATED SNOW SHOWERS TO DEVELOP DURING THE AFTERNOON. THE FLOW ALOFT BECOMES INCREASINGLY SOUTHWEST ON THURSDAY AND FRIDAY AS A DEEP UPPER TROF DIGS ALONG THE WEST COAST. ENOUGH MOISTURE AND INSTABILITY WILL RIDE INTO THE STATE TO PROVIDE FOR ISOLATED SNOW SHOWERS ON BOTH DAYS. TEMPERATURES WILL REMAIN BELOW SEASONAL AVERAGES THROUGH THE PERIOD. && .PRELIMINARY POINT TEMPS/POPS... GTF 33 36 30 44 / 10 20 20 20 CTB 28 38 25 43 / 10 40 20 20 HLN 27 35 25 42 / 10 50 40 50 BZN 26 32 21 41 / 20 80 30 40 WEY 19 25 14 30 / 80 100 60 60 DLN 24 30 20 38 / 20 60 40 50 HVR 31 42 25 44 / 10 40 20 20 LWT 29 35 24 41 / 10 30 30 20 && .TFX WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING UNTIL 5 AM MST SATURDAY EASTERN GLACIER... NORTHERN ROCKY MOUNTAIN FRONT...SOUTHERN ROCKY MOUNTAIN FRONT. WINTER WEATHER ADVISORY UNTIL 11 AM MST SATURDAY NORTHERN ROCKY MOUNTAIN FRONT...SOUTHERN ROCKY MOUNTAIN FRONT. WINTER WEATHER ADVISORY UNTIL 3 PM MST SATURDAY BEAVERHEAD... GALLATIN...MADISON. HIGH WIND WARNING UNTIL 5 AM MST SATURDAY FERGUS...JUDITH BASIN. && WEATHER.GOV/GREATFALLS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GREAT FALLS MT 917 PM MST FRI NOV 11 2011 MTZ009-048-130430- NORTHERN ROCKY MOUNTAIN FRONT-SOUTHERN ROCKY MOUNTAIN FRONT- 917 PM MST FRI NOV 11 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL MONTANA. .DAY ONE...TONIGHT A HIGH WIND WARNING REMAINS IN EFFECT THROUGH TONIGHT. A WINTER WEATHER ADVISORY FOR SNOW AND BLOWING SNOW REMAINS IN EFFECT. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY THE WINTER WEATHER ADVISORY FOR SNOW AND BLOWING SNOW WILL CONTINUE IN EFFECT UNTIL 11 AM MST SATURDAY. .SPOTTER INFORMATION STATEMENT... REPORTS OF STRONG WINDS OR WIND DAMAGE WOULD BE GREATLY APPRECIATED. MTZ010>014-044>047-049-052>054-130430- EASTERN GLACIER-HILL-CASCADE-CHOUTEAU- CENTRAL AND SOUTHERN LEWIS AND CLARK-TOOLE-LIBERTY- EASTERN PONDERA-BLAINE-EASTERN TETON-JEFFERSON-BROADWATER-MEAGHER- 917 PM MST FRI NOV 11 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL MONTANA...NORTH CENTRAL MONTANA AND SOUTHWEST MONTANA. .DAY ONE...TONIGHT THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. MTZ008-015-055-130430- BEAVERHEAD-MADISON-GALLATIN- 917 PM MST FRI NOV 11 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST MONTANA. .DAY ONE...TONIGHT A WINTER WEATHER ADVISORY FOR SNOW AND BLOWING SNOW WILL BE IN EFFECT BEGINNING AT 11 PM MST. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY THE WINTER WEATHER ADVISORY FOR SNOW AND BLOWING SNOW WILL CONTINUE IN EFFECT UNTIL 2 PM MST SATURDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. MTZ050-051-130430- JUDITH BASIN-FERGUS- 917 PM MST FRI NOV 11 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL MONTANA. .DAY ONE...TONIGHT A HIGH WIND WARNING REMAINS IN EFFECT. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... REPORTS OF STRONG WINDS OR WIND DAMAGE WOULD BE GREATLY APPRECIATED.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1057 PM MST FRI NOV 11 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0400 PM NON-TSTM WND GST 8 SE EAST GLACIER PARK 48.37N 113.10W
11/11/2011 M76 MPH GLACIER MT MESONET
76 MPH WIND GUST AT THE DEEP CREEK RAWS LOCATION.
&&
BRUSDAPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1058 PM MST FRI NOV 11 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0700 AM NON-TSTM WND GST 13 WSW SAINT MARY 48.69N 113.71W
11/11/2011 M87 MPH GLACIER MT MESONET
87 MPH WIND GUST AT THE LOGAN PASS VISITOR CENTER.
&&
BRUSDAPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1102 PM MST FRI NOV 11 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1022 AM NON-TSTM WND GST 1 N LOMA 47.95N 110.50W
11/11/2011 M52 MPH CHOUTEAU MT DEPT OF HIGHWAYS
52 MPH WIND GUST AT THE LOMA DOT SENSOR.
&&
BRUSDAPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1116 PM MST FRI NOV 11 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0900 PM NON-TSTM WND GST 7 S NEIHART 46.84N 110.72W
11/11/2011 M51 MPH MEAGHER MT MESONET
51 MPH PEAK WIND GUST AT THE PORPHYRY PEAK RAWS
LOCATION.
&&
BRUSDAPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1150 PM MST FRI NOV 11 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1139 PM NON-TSTM WND GST 4 NNE MCALLISTER 45.50N 111.70W
11/11/2011 M55 MPH MADISON MT DEPT OF HIGHWAYS
55 MPH WIND GUST AT THE NORRIS HILL DOT SENSOR.
&&
BRUSDAPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1248 AM MST SAT NOV 12 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1200 AM HIGH SUST WINDS 4 NNE MCALLISTER 45.50N 111.70W
11/12/2011 M43 MPH MADISON MT DEPT OF HIGHWAYS
SUSTAINED WINDS OVER 40 MPH FROM 930 PM THROUGH
MIDNIGHT AT THE DOT SENOR ON NORRIS HILL.
&&
BRUSDA6 winter storm. Local standard time, as filed.
Eight inches of snow fell at East Glacier Park 11SSW (the Pike Creek SNOTEL site - elevation 5900 feet.
Twelve inches of snow fell at Lincoln 9NNW (the Copper Camp SNOTEL site - elevation 6950 feet).
Nine inches of snow fell at West Yellowstone 11S (the Black Bear SNOTEL site - elevation 7900 feet).
Eight inches of snow fell at Highwood 11ESE.
Fourteen inches of snow fell at Lincoln 9NNW (the Copper Camp SNOTEL site - elevation 6950 feet).
Thirteen inches of snow fell at Bynum 12WSW.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2011Every state in 2011This day in weather historyWarnings in Montana, November 2011
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: 352134, 352135, 352136, 352137, 352138, 352139.