A tight surface gradient resulted in high winds along the Northern Rocky Mountain Front.
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 tight surface gradient resulted in high winds along the Northern Rocky Mountain Front.
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 Jan 9, 10:40 AM MST, 16 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREAT FALLS MT 1040 AM MST SAT JAN 9 2010 UPDATED AVIATION SECTION .DISCUSSION... ISSUED A HIGH WIND WARNING FOR THE NORTHERN ROCKY MOUNTAIN FRONT. INCREASED STRENGTH OF CHINOOK WINDS AHEAD OF SHORTWAVE THAT SHOULD ALLOW FOR AN INCREASE IN WIND STRENGTH THROUGH THE EVENING. THIS COULD ALSO CAUSE SOME BLOWING SNOW WHERE TEMPERATURES ARE STILL BELOW FREEZING IN THE HIGH ELEVATIONS. SLIGHTLY ADJUSTED TEMPERATURES TO GO ALONG WITH THE STRONGER CHINOOK WINDS. OTHERWISE NO OTHER MAJOR CHANGES TO THE FORECAST. SUK && .AVIATION... UPDATED 1740Z. MID AND UPPER LEVEL CLOUDS WILL CONTINUE TO MOVE ACROSS THE AREA EMBEDDED WITHIN THE WESTERLY FLOW ALOFT. SURFACE GRADIENTS WILL REMAIN TIGHT ALONG THE NORTHERN ROCKY MOUNTAIN FRONT PROVIDING STRONG WINDS THROUGH 03Z. A STRONG VALLEY INVERSION PERSISTS AT KHLN WITH PATCHY FOG CONTINUING. VFR CONDITIONS PREVAIL WITH MVFR CONDITIONS...AT TIMES...AT KHLN DUE TO LOW CLOUDS AND FOG. && .HYDROLOGY... A FLOOD WARNING REMAINS IN EFFECT UNTIL FURTHER NOTICE FOR THE GALLATIN RIVER BECAUSE OF ICE JAMS. ICE JAMS ARE CAUSING THE RIVER TO GO OVER ITS BANKS JUST SOUTH OF BIG SKY. THIS ICE JAM IS ANTICIPATED TO PERSIST. DEPENDING ON HOW THE ICE WILL EVENTUALLY BREAK...SIGNIFICANT IMPACTS COULD RESULT DOWNSTREAM. A SIGNIFICANT WARM UP THIS WEEKEND COULD CAUSE THE SNOW MELT T0 INCREASE THE WATER IN THE RIVER CHANNEL AND COMPOUND THE SITUATION. && .PREV DISCUSSION... /ISSUED 355 AM MST SAT JAN 9 2010/ TODAY THROUGH MONDAY NIGHT...OVERALL A FAIRLY QUIET WEATHER PATTERN WILL RESIDE OVER THE REGION DURING THE PERIOD...WITH A NICE JANUARY THAW EXPECTED. A WEAK PACIFIC WEATHER DISTURBANCE WILL MOVE EASTWARD INTO THE ROCKY MOUNTAIN FRONT REGION LATER THIS MORNING. EXPECT INCREASING CHANCES FOR RAIN AND SNOW SHOWERS OVER THE ROCKIES...BUT AS THE SYSTEM MOVES EASTWARD...IT WILL CONTINUE TO WEAKEN. THUS ANY SNOW ACCUMULATIONS WILL MAINLY BE OVER THE HIGHER MOUNTAINS...WITH A RAIN/SNOW MIX POSSIBLE THIS AFTERNOON AT LOWER ELEVATIONS NEAR THE FRONT RANGE. ELSEWHERE...A NICE JANUARY THAW IS EXPECTED...AS AFTERNOON HIGHS CLIMB INTO THE 30S AND 40S. HOWEVER...BOTH THE HELENA VALLEY AND THE HARLEM AREA WILL PROBABLY HAVE ANOTHER DAY OF COLD AIR TRAPPED AT LOWER ELEVATIONS...THUS THERE TEMPERATURES ARE A BIT LOWER. THE HAVRE AREA SHOULD MIX OUT BY LATE AFTERNOON...THUS HIGH TEMPERATURES ARE WARMER THEN RECENT IN THAT REGION. IT WILL BE BREEZY TODAY ALONG THE FRONT RANGE OF THE ROCKIES...BUT WIND SPEEDS SHOULD REMAIN BELOW WARNING CRITERIA. FOR SUNDAY THROUGH MONDAY NIGHT...GENERALLY A DRY PERIOD OF WEATHER WITH ONLY A VERY ISOLATED MOUNTAIN SHOWER POSSIBLE. TEMPERATURES WILL CONTINUE TO BE ABOVE NORMAL...EVEN AT NIGHT. THE WARMER AIR SHOULD ALSO MAKE IT INTO MOST VALLEYS OF SOUTHWEST MONTANA AND THE HARLEM AREA BY MONDAY. BRUSDA TUESDAY THROUGH SATURDAY NIGHT...PROGRESSIVE PATTERN IS FORECAST TO CONTINUE WITH A SERIES OF UPPER RIDGES AND UPPER TROUGHS TO AFFECT THE AREA. THERE ARE DIFFERENCES AMONGST THE MODELS WITH THE TIMING AND STRENGTH OF THE UPPER TROUGHS PARTICULARLY OVER THE WEEKEND. IN LINE WITH THE DIFFERENCES WITH THE UPPER TROUGHS THERE ARE DIFFERENCES AMONGST THE MODELS WITH FORECAST PRECIPITATION. THE LATEST ECMWF MODEL SEEMS TO BE MORE IN LINE WITH OTHER GUIDANCE SO LEANED TOWARDS USING IT AS A BASIS FOR THE FORECAST. FOR WEDNESDAY NIGHT THE ECMWF MODEL BROUGHT MORE PRECIPITATION TO CENTRAL AND SOUTHERN PORTIONS OF THE FORECAST AREA THAN THE PREVIOUS RUN OF THE GFS MODEL SO INCREASED THE CHANCES OF PRECIPITATION EXCEPT IN THE NORTH FOR WEDNESDAY NIGHT. AN EVEN BIGGER DIFFERENCE BETWEEN THE GFS AND ECMWF MODELS OCCURS OVER THE WEEKEND AS THE GFS BRINGS A WEATHER SYSTEM FROM CANADA THROUGH THE AREA WITH SIGNIFICANT PRECIPITATION AND COOLER TEMPERATURES. THE ECMWF ON THE OTHER HAND BRINGS A PACIFIC WEATHER SYSTEM INTO THE AREA LATE SATURDAY NIGHT WITH MOST OF THE PRECIPITATION CONFINED TO THE MOUNTAINS. THE ECMWF ALSO HAS WARMING TEMPERATURES INTO THE WEEKEND. WARMED TEMPERATURES IN LINE WITH THE ECMWF BUT WAS RELUCTANT TO GO AS DRY AS THE ECMWF SO WENT WITH A CHANCE OF PRECIPITATION OVER THE MOUNTAINS AND A SLIGHT CHANCE OF PRECIPITATION FOR THE PLAINS/VALLEYS FOR SATURDAY AND SATURDAY NIGHT. BLANK && .PRELIMINARY POINT TEMPS/POPS... GTF 45 30 46 31 / 0 0 0 0 CTB 45 26 45 23 / 0 0 0 0 HLN 19 13 35 15 / 10 10 10 0 BZN 27 13 37 12 / 0 0 0 0 WEY 24 -3 30 -9 / 10 10 0 0 DLN 34 18 40 17 / 10 10 10 0 HVR 38 16 39 14 / 0 0 0 0 LWT 44 23 45 24 / 0 0 0 0 && .TFX WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING UNTIL 8 PM MST THIS EVENING FOR NORTHERN ROCKY MOUNTAIN FRONT. AN AIR STAGNATION ADVISORY REMAINS IN EFFECT UNTIL FURTHER NOTICE FOR THE HELENA VALLEY INCLUDING THE CITY OF HELENA. A FLOOD WARNING CONTINUES FOR THE GALLATIN RIVER IN GALLATIN COUNTY UNTIL FURTHER NOTICE. && SHORT TERM...SUK LONG TERM...BLANK AVIATION...EMANUEL WEATHER.GOV/GREATFALLS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GREAT FALLS MT 952 AM MST SAT JAN 9 2010 MTZ055-101700- GALLATIN- 952 AM MST SAT JAN 9 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST MONTANA. .DAY ONE...TODAY AND TONIGHT A FLOOD WARNING REMAINS IN EFFECT FOR THE GALLATIN RIVER DUE TO ICE JAMS...ESPECIALLY NEAR RAINBOW RANCH. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY A FLOOD WARNING REMAINS IN EFFECT UNTIL FURTHER NOTICE FOR THE GALLATIN RIVER DUE TO ICE JAMS...ESPECIALLY NEAR RAINBOW RANCH. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ014-101700- CENTRAL AND SOUTHERN LEWIS AND CLARK- 952 AM MST SAT JAN 9 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST MONTANA. .DAY ONE...TODAY AND TONIGHT AN AIR STAGNATION ADVISORY REMAINS IN EFFECT FOR THE HELENA VALLEY INCLUDING THE CITY OF HELENA. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY AN AIR STAGNATION ADVISORY REMAINS IN EFFECT UNTIL FURTHER NOTICE FOR THE HELENA VALLEY INCLUDING THE CITY OF HELENA. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ009-101700- NORTHERN ROCKY MOUNTAIN FRONT- 952 AM MST SAT JAN 9 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL MONTANA. .DAY ONE...TODAY AND TONIGHT A HIGH WIND WARNING HAS BEEN ISSUED THROUGH 8 PM FOR THE NORTHERN ROCKY MOUNTAIN FRONT SUSTAINED WINDS IN EXCESS OF 40 MPH WITH GUSTS EXCEEDING 65 ARE LIKELY ESPECIALLY ALONG FAVORED TERRAIN. BLOWING AND DRIFTING SNOW COULD ALSO IMPACT THE AREA REDUCING VISIBILITIES TO LESS THAN ONE QUARTER MILE AT TIMES. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ008-010>013-015-044>054-101700- BEAVERHEAD-EASTERN GLACIER-HILL-CASCADE-CHOUTEAU-MADISON-TOOLE- LIBERTY-EASTERN PONDERA-BLAINE-SOUTHERN ROCKY MOUNTAIN FRONT- EASTERN TETON-JUDITH BASIN-FERGUS-JEFFERSON-BROADWATER-MEAGHER- 952 AM MST SAT JAN 9 2010 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...SUNDAY THROUGH FRIDAY THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
1 high wind. Local standard time, as filed.
Sustained winds of 35 mph were reported at the Two Medicine DOT site.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2010Every state in 2010This day in weather historyWarnings in Montana, January 2010
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: 208076.