-Canadian Border. The resulting surface gradient produced strong winds across North Central Montana.
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 series of low pressure troughs moved along the U.S.-Canadian Border. The resulting surface gradient produced strong winds across North Central Montana. Wind gusts in excess of 60 mph 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 Dec 23, 4:30 AM MST, 2 hours earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREAT FALLS MT 430 AM MST FRI DEC 23 2011 UPDATED AVIATION DISCUSSION .DISCUSSION... TODAY THROUGH CHRISTMAS EVENING...LATEST ANALYSIS SHOWS FORECAST STILL ON TRACK FOR DRY AND MILD CONDITIONS THRU THE HOLIDAY WEEKEND. NRN ROCKIES CURRENTLY LOCATED IN THE EASTERN PORTION OF A BROAD UPPER LEVEL RIDGE CENTERED OFF THE PACIFIC COAST. SERIES OF SHORTWAVE TROFS EJECTING FROM A DEEP CLOSED UPPER LEVEL LOW PRESSURE SYSTEM IN THE WESTERN GULF OF ALASKA WILL MOVE THRU THE NORTHERN FRINGES OF THE RIDGE TODAY AND TOMORROW...BRINGING PERIODS OF INCREASED CLOUD COVER OVER OUR REGION AND JUST A SLIGHT CHANCE OF LIGHT SNOW SHOWERS OVER THE ROCKY MTN FRONT. FORECAST MODELS STILL INDICATING STRONG WINDS DEVELOPING ALONG THE ROCKY MTN FRONT...AND POSSIBLY OVER THE ADJACENT PLAINS...AS SURFACE PRESSURE GRADIENT TIGHTENS BETWEEN A LEESIDE TROF OVER THE HILINE/CENTRAL PLAINS AND HIGH PRESSURE WEST OF THE CONTINENTAL DIVIDE. CYCLES OF GRADIENT/WIND SPEED WEAKENING AND RE-STRENGTHENING DUE TO DIURNAL EFFECTS AND LULL PERIODS BETWEEN PASSAGE OF THE AFOREMENTIONED SHORTWAVE TROFS ARE EXPECTED THRU SUNDAY. THUS CURRENT HIGH WIND WARNING FOR THE ROCKY MTN FRONT AND HIGH WIND WATCH FOR ERN GLACIER COUNTY REMAIN IN EFFECT WITH NO CHANGES AT THIS TIME. REST OF THE HILINE AND CENTRAL PLAINS WILL ALSO SEE BREEZY TO GUSTY CONDITIONS WITH WIDESPREAD GUSTS OF 30-40 MPH. WINDS ALOFT GRADUALLY TRANSITION FROM NORTHWEST TO WESTERLY DIRECTION AS THE UPPER RIDGE AXIS MOVES INTO GREAT BASIN BY SUNDAY...CREATING INCREASED DOWNSLOPE FLOW THAT WILL KEEP AFTN HIGH TEMPERATURES 10-15 DEGREES ABOVE NORMAL THRU THE WEEKEND. FOR TODAY...MID 40S ARE EXPECTED OVER CENTRAL AND NORTH CENTRAL MT WITH MID 30S ACROSS THE SOUTHWEST COUNTIES. TEMPS CLIMB INTO THE UPPER 30S TO UPPER 40S ON SAT AND TO A VERY UN-CHRISTMAS-LIKE LOW 50S OVER THE NORTHERN AND CENTRAL PLAINS AND LOW/MID 40S OVER SOUTHWEST MT. WARANAUSKAS SUNDAY NIGHT THROUGH FRIDAY...MEDIUM RANGE MODELS ARE IN FAIR AGREEMENT THROUGH NEXT WEEK...INDICATING A FAST ZONAL/WESTERLY FLOW ALOFT. SEVERAL WAVES OF UPPER LEVEL ENERGY WITHIN THE FLOW WILL BRING PERIODS OF MOUNTAIN SNOW WITH DOWNSLOPE WINDS GENERALLY KEEPING THE PLAINS AND LARGER VALLEYS DRY WITH PERIODS OF STRONG WINDS AS UPPER LEVEL SYSTEMS AND ASSOCIATED SURFACE TROUGHS MOVE ACROSS THE REGION. SYSTEM MOVING THROUGH SUNDAY NIGHT WILL LIKELY BRING STRONG WINDS TO AT LEAST THE ROCKY MTN FRONT AREA AND ADJACENT PLAINS. FAVORABLE POSITIONING OF A STRONG UPPER LEVEL JET COMING IN FROM THE WEST AND WARM ADVECTION IN THE MID LEVELS MAY BRING A PERIOD OF LIGHT SNOW TO THE PLAINS TUES NIGHT AND WEDNESDAY...MAINLY TO AREAS EAST OF I-15. AREAS ALONG THE CONTINENTAL DIVIDE NORTH OF ROGERS PASS WILL LIKELY SEE SEVERAL ROUNDS OF MEASURABLE SNOWFALL WED THRU FRI AS WAVES OF ENERGY AND MOISTURE MOVE THROUGH THE FAST WESTERLY FLOW ALOFT WITH STRONG DOWNSLOPE WINDS AND GENERALLY DRY CONDITIONS TO THE EAST OVER NORTH CENTRAL MT. TEMPERATURES WILL REMAIN 5 TO 15 DEGREES ABOVE SEASONAL AVERAGES THROUGH THE PERIOD. HOENISCH && .AVIATION... UPDATED 1200Z. VFR CONDITIONS WILL CONTINUE THROUGH TODAY AND TONIGHT AS AN UPPER LEVEL RIDGE MAINTAINS DRY CONDITIONS WITH JUST A PERIOD OF BROKEN HIGH LEVEL CLOUDS THIS AFTERNOON AS A WEAK DISTURBANCE MOVES THROUGH THE REGION. STRONG SW SURFACE WINDS WILL CONTINUE ALONG THE ROCKY MTN FRONT AND ADJACENT PLAINS WITH INCREASING WINDS THROUGH THIS MORNING OVER MUCH OF NORTH CENTRAL MT. HOENISCH && .PRELIMINARY POINT TEMPS/POPS... GTF 44 29 48 33 / 0 0 10 0 CTB 41 27 45 31 / 0 0 10 0 HLN 36 20 41 25 / 0 0 0 0 BZN 36 11 40 15 / 0 0 0 0 WEY 20 -6 25 2 / 0 10 10 0 DLN 36 16 39 20 / 0 0 0 0 HVR 44 25 47 28 / 0 0 0 0 LWT 43 24 45 29 / 0 0 0 0 && .TFX WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING UNTIL 11 PM MST SUNDAY NORTHERN ROCKY MOUNTAIN FRONT...SOUTHERN ROCKY MOUNTAIN FRONT. HIGH WIND WATCH FROM THIS EVENING THROUGH SUNDAY EVENING EASTERN GLACIER. WINTER WEATHER ADVISORY UNTIL NOON MST TODAY CENTRAL AND SOUTHERN LEWIS AND CLARK. && SHORT TERM...WARANAUSKAS LONG TERM...HOENISCH AVIATION...HOENISCH WEATHER.GOV/GREATFALLS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GREAT FALLS MT 452 AM MST FRI DEC 23 2011 MTZ009-048-241200- NORTHERN ROCKY MOUNTAIN FRONT-SOUTHERN ROCKY MOUNTAIN FRONT- 452 AM MST FRI DEC 23 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL MONTANA. .DAY ONE...TODAY AND TONIGHT A HIGH WIND WARNING IS IN EFFECT TODAY THROUGH TONIGHT. PERIODS OF SUSTAINED WINDS OF 35 TO 45 MPH WITH GUSTS OF 60 TO 75 MPH ARE EXPECTED TO OCCUR...WITH OCCASIONAL BREAKS OF REDUCED WIND SPEEDS. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY THE HIGH WIND WARNING REMAINS IN EFFECT UNTIL 11 PM SUNDAY NIGHT. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS REQUIRED FOR TODAY THROUGH SUNDAY. PLEASE SEND REPORTS OF STRONG WINDS OR WIND DAMAGE TO THE NATIONAL WEATHER SERVICE OFFICE IN GREAT FALLS. MTZ010-241200- EASTERN GLACIER- 452 AM MST FRI DEC 23 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL MONTANA. .DAY ONE...TODAY AND TONIGHT A HIGH WIND WATCH IS IN EFFECT BEGINNING THIS EVENING. SUSTAINED WINDS OF 30 TO 40 MPH WITH GUSTS OF 60 TO 65 MPH ARE POSSIBLE. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY THE HIGH WIND WATCH CONTINUES THROUGH SUNDAY EVENING. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS REQUIRED THIS EVENING THROUGH SUNDAY. PLEASE SEND REPORTS OF STRONG WINDS OR WIND DAMAGE TO THE NATIONAL WEATHER SERVICE OFFICE IN GREAT FALLS. MTZ014-241200- CENTRAL AND SOUTHERN LEWIS AND CLARK- 452 AM MST FRI DEC 23 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST MONTANA. .DAY ONE...TODAY AND TONIGHT A WINTER WEATHER ADVISORY FOR BLOWING SNOW IS IN EFFECT UNTIL NOON TODAY FOR THE AREA FROM BOWMANS CORNER TO LINCOLN. WIND GUSTS NEAR 30 MPH WILL GENERATE BLOWING SNOW THAT WILL RESTRICT VISIBILITIES ALONG MONTANA HIGHWAY 200...ESPECIALLY NEAR ROGERS PASS. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... PLEASE SEND REPORTS OF HAZARDOUS TRAVEL CONDITIONS IN THE ADVISORY AREA TO THE NATIONAL WEATHER SERVICE OFFICE IN GREAT FALLS. MTZ008-011>013-015-044>047-049>055-241200- BEAVERHEAD-HILL-CASCADE-CHOUTEAU-MADISON-TOOLE-LIBERTY- EASTERN PONDERA-BLAINE-EASTERN TETON-JUDITH BASIN-FERGUS- JEFFERSON-BROADWATER-MEAGHER-GALLATIN- 452 AM MST FRI DEC 23 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL MONTANA...NORTH CENTRAL MONTANA AND SOUTHWEST MONTANA. .DAY ONE...TODAY AND 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.
9 high wind. Local standard time, as filed.
A wind gust to 63 mph was reported at Bynum 13W (the Dellwo MSCN site).
A wind gust to 66 mph was reported at the Heart Butte RAWS site.
A wind gust to 60 mph was reported at the Cut Bank ASOS site.
A wind gust to 58 mph was reported at Geyser 7E (the Bravo RAWS site).
A wind gust to 79 mph was reported at Hilger 7SE (the Judith Peak RAWS site).
Sustained wind speeds of 61 mph were reported at Whitlash 8W for several hours.
Sustained wind speeds of 61 mph were reported at Whitlash 8W for several hours.
A wind gust to 64 mph was reported at Townsend 8W.
A wind gust to 64 mph was reported at Chinook 11S.
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, December 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: 354872, 354860, 354862, 354878, 354879, 354867, 354869, 354873, 354871.