Deep surface low pressure moving across Southern Alberta contributed to a strong pressure gradient resulting in high winds along the Rocky Mountain Front. Wind gusts in excess of 58 mph 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.
Deep surface low pressure moving across Southern Alberta contributed to a strong pressure gradient resulting in high winds along the Rocky Mountain Front. Wind gusts in excess of 58 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 Sep 26, 8:35 AM MST, 25 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREAT FALLS MT 935 AM MDT SAT SEP 26 2009 .UPDATE...GOING FORECAST IS IN GENERALLY GOOD SHAPE WITH WARM AND WINDY CONDITIONS EXPECTED ACROSS THE REGION TODAY. HAVE MADE UPDATES TO BUMP TEMPERATURES UP A FEW DEGREES IN MOST LOCATIONS THIS AFTERNOON. HAVE ALSO MADE TWEAKS TO SKY CONDITION TO ACCOUNT FOR THE CHINOOK ARCH THAT IS SPREADING SOUTH THIS MORNING. WINDS STILL EXPECTED TO BECOME STRONG AND GUSTY...ESPECIALLY ALONG THE ROCKY MOUNTAIN FRONT...THIS AFTERNOON. HIGH WIND WARNING FOR THE ROCKY MOUNTAIN FRONT AND THE RED FLAG WARNING FOR THE ENTIRE FORECAST AREA WILL BOTH REMAIN IN EFFECT. MPJ && .AVIATION... UPDATED 1130Z. SURFACE WINDS ARE INCREASING ACROSS THE ROCKY MOUNTAIN FRONT THIS MORNING AND WILL SPREAD TO ALL OF NORTH CENTRAL MONTANA DURING THE MORNING HOURS AND SOUTHWEST MONTANA BY AFTERNOON...AS A LEE SIDE TROUGH DEVELOPS ACROSS CENTRAL MONTANA. EXPECT SOME GUSTS TO AROUND 60 KTS ACROSS THE EAST SLOPES OF THE ROCKY MOUNTAINS BY 16Z. WINDS WILL DECREASE AND BECOME NORTHWESTERLY AFTER 02Z. VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST PERIOD. WILLIAMSON DC && .FIRE WEATHER... CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED THROUGH SATURDAY EVENING AS WIDESPREAD STRONG WESTERLY WINDS COMBINE WITH WARM AND DRY CONDITIONS ACROSS NORTHERN...CENTRAL...AND SOUTHWEST MONTANA. RED FLAG WARNING REMAINS IN EFFECT FROM NOON THROUGH MIDNIGHT. A COLD FRONT WILL MOVE THROUGH PORTIONS OF NORTHERN AND CENTRAL MONTANA SATURDAY NIGHT WITH WINDS SHIFTING TO THE NORTHWEST AFTER MIDNIGHT. ON SUNDAY...COOLER TEMPERATURES...LOWER WIND SPEEDS...AND RELATIVE HUMIDITIES RECOVERING ABOVE 20 PERCENT WILL REDUCE FIRE DANGER CONDITIONS OVER THE REGION. MLS && .PREV DISCUSSION... /ISSUED 530 AM MDT SAT SEP 26 2009/ TODAY THROUGH MONDAY...GUSTY WEST WINDS WILL DEVELOP LATER THIS MORNING AS STRONG UPPER-LEVEL JET STREAM ENERGY COUPLED WITH AN UPPER-LEVEL SHORTWAVE PUSHES INTO SOUTHERN CANADA. THUS HAVE UPGRADED HIGH WIND WATCH TO A HIGH WIND WARNING AND ALSO EXPANDED THE AFFECTED AREA TO INCLUDE ALL ELEVATIONS ALONG THE NORTHERN AND SOUTHERN ROCKY MOUNTAIN FRONT...STARTING LATER THIS MORNING AND CONTINUING THROUGH SUNSET. SUSTAINED WINDS OF 25 TO 40 MPH WITH OCCASIONAL GUSTS EXCEEDING 60 MPH POSSIBLE. WIDESPREAD WARM...WINDY AND DRY CONDITIONS ARE EXPECTED ACROSS ALL OF CENTRAL AND SOUTHWEST MONTANA TODAY. THESE CONDITIONS WILL AFFECT CURRENT ACTIVE WILDLAND FIRES...ALONG AND EAST OF THE CONTINENTAL DIVIDE...SO HAVE CONTINUED RED FLAG WARNING FOR ALL LOCAL FIRE WEATHER ZONES EFFECTIVE FROM NOON THROUGH MIDNIGHT. WINDS WILL VEER TO THE NORTHWEST LATER THIS EVENING AS A WEAK SURFACE COLD FRONT SLIDES THROUGH THE AREA. WHILE BREEZY CONDITIONS ARE STILL ANTICIPATED OVERNIGHT...WINDS SHOULD STAY BELOW HIGH WIND WARNING CRITERIA. LITTLE MOISTURE IS ASSOCIATED WITH THE COLD FRONT SO HAVE INCLUDED ONLY A SLIGHT CHANCE OF MORNING SHOWERS ON SUNDAY ALONG THE HI-LINE WHERE MORE LIFT WILL BE PRESENT. IN THE WAKE OF THE FRONT ON SUNDAY...COOLER MORE SEASONAL TEMPERATURES AND BREEZY NORTH WINDS ARE EXPECTED ALONG WITH PARTLY CLOUDY SKIES. UPPER-LEVEL RIDGE WILL BUILD OVER THE REGION ON SUNDAY NIGHT WITH LIGHTER WINDS AND TEMPERATURES FALLING TO NEAR FREEZING IN MANY LOCATIONS UNDER MAINLY CLEAR SKIES. RIDGE AXIS WILL MOVE OVER THE STATE ON MONDAY WITH SOUTHWEST FLOW ALOFT AND SLIGHTLY ABOVE AVERAGE TEMPERATURES EXPECTED BEFORE MORE SIGNIFICANT CHANGES ARRIVE BY THE MIDDLE OF NEXT WEEK. MLS MONDAY NIGHT THROUGH THURSDAY...FORECAST STILL ON TRACK FOR FIRST STRONG AUTUMN STORM SYSTEM TO ARRIVE MIDWEEK. UPPER LEVEL RIDGE OVER ERN MT ON MON EVE WILL MOVE STEADILY DOWNSTREAM OVERNIGHT. DRY CONDITIONS ASSOCIATED WITH THE RIDGE SHOULD PERSIST EAST OF THE DIVIDE THROUGH MIDDAY ON TUES. WEAKENING RIDGE WILL BE STEADILY REPLACED BY STRONG PACIFIC TROF THAT REACHES WA/OR COAST LATE MON NIGHT. LATEST MODEL RUNS HAVE COME INTO BETTER AGREEMENT THAN DISCUSSED YESTERDAY ON THE PROGRESSION OF THIS SYSTEM INTO THE NRN ROCKIES. OVERALL TREND IS CLOSER TO THE EUROPEAN MODEL SOLUTION WHICH FAVORS A SLOWER AND WETTER EVOLUTION FROM TUES TO THURS. LEADING EDGE OF MOISTURE AND SURFACE COLD FRONT REACHES WESTERN MT BY MIDDAY TUES...WITH SOME SHOWERS POSSIBLE IN SW MT BY NOON. THE SURFACE FRONT SHOULD MOVE ACROSS CENTRAL MT DURING LATE AFTN ON TUES WHERE ENHANCED INSTABILITY WILL SPARK AREAS OF SHOWERS AND A FEW THUNDERSTORMS AS IT MOVES EASTWARD. BUT PRECIPITATION COVERAGE WILL INITIALLY BE A BIT SPOTTY AS BULK OF MOISTURE REMAINS WEST OF THE DIVIDE UNTIL TUES NIGHT WHEN IT ARRIVES ALONG WITH THE TROF AXIS AND ACCOMPANYING CHILLY CANADIAN AIRMASS. PRECIP BECOMES MUCH MORE WIDESPREAD OVERNIGHT TUES INTO WED SO HAVE INCREASED POPS INTO LIKELY CATEGORY FOR ALL BUT NORTHEAST CORNER OF THE GREAT FALLS CWA. AS COLDER AIR PLUNGES INTO THE PLAINS...SNOW LEVELS DROP INTO THE 4000 TO 5000 FT RANGE ON WED...RESULTING IN ARRAY OF PRECIP WITH RAIN AND RAIN/SNOW MIX AT LOWER ELEVATIONS AND SLEET/SNOW SHOWERS FOR THE MOUNTAINS. SNOW ACCUMULATIONS OF AN INCH OR TWO ARE POSSIBLE OVER HIGHER TERRAIN. GUSTY NORTHWEST WINDS ARE EXPECTED ON WED AS WELL. TROF AXIS SHOULD MOVE INTO ERN MT BY THURS MORNING BRINGING GRADUALLY CLEARING SKIES FROM WEST TO EAST ACROSS CENTRAL AND SW MT. AS FOR TEMPERATURES...THOUGH THERE WILL BE STRONG SOUTHWEST FLOW ALOFT ON TUES...AFTN HIGHS WILL ONLY REACH MID 60S TO LOW 70S AS CLOUD COVER AHEAD OF THE PACIFIC TROF AND AFTN ARRIVAL OF THE COLD FRONT WILL LIMIT WARMING. AFTER THAT...TEMPS WILL BE WELL BELOW NORMAL ON WED AND THURS...WITH BROAD AREAS OF BELOW FREEZING TEMPS WED AND THURS NIGHT. WARANAUSKAS FRIDAY AND SATURDAY...UNSETTLED NORTHWEST FLOW REGIME SETS UP OVER THE REGION FOLLOWING THE DEPARTURE OF THE MIDWEEK STORM SYSTEM. EARLY FRIDAY LOOKS DRY AND COOL BUT A SHORTWAVE TROF SKIRTING THE US/CAN BORDER FRI AFTN/EVE WILL BRING A SLIGHT CHANCE OF RAIN SHOWERS OVER THE PLAINS AND SOUTHWEST VALLEYS WITH LIGHT SNOW SHOWERS OVER THE MOUNTAINS. UPPER FLOW TURNS MORE WESTERLY ON SAT AHEAD OF A SECOND SLIGHTLY DEEPER UPPER LEVEL TROF MOVING INTO SRN BC/ALB. MOISTURE FROM THIS SYSTEM SHOULD ARRIVE SAT AFTN/EVE...GENERATING ANOTHER ROUND OF RAIN SHOWERS AND MOUNTAIN SNOW. TEMPERATURES WILL REMAIN ABOUT 5 TO 8 DEGREES BELOW NORMAL THROUGH THIS PERIOD. WARANAUSKAS && .PRELIMINARY POINT TEMPS/POPS... GTF 83 40 61 33 / 0 0 0 0 CTB 79 36 60 32 / 0 10 10 0 HLN 83 47 68 38 / 0 0 0 0 BZN 88 41 72 33 / 0 0 0 0 WEY 78 26 68 24 / 0 0 0 0 DLN 82 41 71 37 / 0 0 0 0 HVR 85 39 61 29 / 0 20 10 0 LWT 83 41 58 31 / 0 10 0 0 && .TFX WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL MIDNIGHT MDT TONIGHT FOR MTZ112>118. HIGH WIND WARNING UNTIL 9 PM MDT THIS EVENING FOR MTZ009-048. && WEATHER.GOV/GREATFALLS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GREAT FALLS MT 534 AM MDT SAT SEP 26 2009 MTZ008-010>015-044>047-049>055-271145- BEAVERHEAD-EASTERN GLACIER-HILL-CASCADE-CHOUTEAU- CENTRAL AND SOUTHERN LEWIS AND CLARK-MADISON-TOOLE-LIBERTY- EASTERN PONDERA-BLAINE-EASTERN TETON-JUDITH BASIN-FERGUS- JEFFERSON-BROADWATER-MEAGHER-GALLATIN- 534 AM MDT SAT SEP 26 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL MONTANA...NORTH CENTRAL MONTANA AND SOUTHWEST MONTANA. .DAY ONE...TODAY AND TONIGHT CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED THROUGH THIS EVENING AS WIDESPREAD STRONG WESTERLY WINDS COMBINE WITH WARM AND DRY CONDITIONS. A RED FLAG WARNING REMAINS IN EFFECT FROM NOON THROUGH MIDNIGHT. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY SIGNIFICANTLY COLDER AIR WILL ARRIVE ON TUESDAY WHEN A COLD FRONT PLUNGES SOUTHWARD ACROSS THE STATE. LOWERING SNOW LEVELS WILL LEAD TO A BROAD MIX OF PRECIPITATION TYPES RANGING FROM RAIN SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT TO A MIX OF RAIN AND SNOW FOR ELEVATIONS BELOW 5000 FEET WITH WIDESPREAD SNOW AT HIGHER ELEVATIONS BEHIND THE FRONT FROM TUESDAY AFTERNOON THROUGH MID DAY WEDNESDAY. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ009-048-271145- NORTHERN ROCKY MOUNTAIN FRONT-SOUTHERN ROCKY MOUNTAIN FRONT- 534 AM MDT SAT SEP 26 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL MONTANA. .DAY ONE...TODAY AND TONIGHT CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED THROUGH THIS EVENING AS WIDESPREAD STRONG WESTERLY WINDS COMBINE WITH WARM AND DRY CONDITIONS. A RED FLAG WARNING REMAINS IN EFFECT FROM NOON THROUGH MIDNIGHT. A HIGH WIND WARNING IS ALSO IN EFFECT THROUGH THIS EVENING FOR THE ROCKY MOUNTAIN FRONT INCLUDING LOGAN PASS...ROGERS PASS AND OTHER FAVORED CANYONS AND MOUNTAIN PASSES. SUSTAINED WINDS OF 25 TO 40 MPH WITH GUSTS EXCEEDING 60 MPH ARE POSSIBLE. THIS WILL ALSO AFFECT CURRENT ACTIVE WILDLAND FIRES ESPECIALLY ALONG AND EAST OF THE CONTINENTAL DIVIDE. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY SIGNIFICANTLY COLDER AIR WILL ARRIVE ON TUESDAY WHEN A COLD FRONT PLUNGES SOUTHWARD ACROSS THE STATE. LOWERING SNOW LEVELS WILL LEAD TO A BROAD MIX OF PRECIPITATION TYPES RANGING FROM RAIN SHOWERS AND THUNDERSTORMS AHEAD OF THE FRONT TO A MIX OF RAIN AND SNOW FOR ELEVATIONS BELOW 5000 FEET WITH WIDESPREAD SNOW AT HIGHER ELEVATIONS BEHIND THE FRONT FROM TUESDAY AFTERNOON THROUGH MID DAY WEDNESDAY. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
2 high wind. Local standard time, as filed.
A wind gust to 59 mph was reported at the Logan Pass Visitors Center in Glacier National Park (elevation 6775 feet).
A wind gust to 62 mph was reported at Babb 9N (the Port of Piegan entry location).
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2009Every state in 2009This day in weather historyWarnings in Montana, September 2009
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: 196108, 196109.