Strong westerly winds aloft resulted in high winds in and around Glacier National Park. Wind gusts in excess of 60 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.
Strong westerly winds aloft resulted in high winds in and around Glacier National Park. 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 Sep 15, 9:25 PM MST, 4 hours 35 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREAT FALLS MT 1025 PM MDT THU SEP 15 2011 AVIATION SECTION UPDATED .UPDATE... NO SIGNIFICANT CHANGES AFTER THE EARLY UPDATE TONIGHT...INCREASED POPS TO ACCOUNT FOR THE SCATTERED LIGHT SHOWERS BEING REPORTED ACROSS THE AREA AHEAD OF THE FRONTAL PASSAGE. CHANGES AFFECTED ONLY POPS...SKY...AND WEATHER. && .AVIATION... UPDATED 0425Z. UPPER LEVEL TROF AND ASSOCIATED SURFACE COLD FRONT CURRENTLY IN WESTERN MT WILL CROSS EAST OF THE CONTINENTAL DIVIDE TONIGHT. PORTIONS OF CENTRAL AND SOUTHWEST MT ALREADY SEEING INCREASING CLOUD COVER AND SOME LIGHT RAIN SHOWERS AHEAD OF THE FRONT...BOTH OF WHICH WILL OVERSPREAD MUCH OF THE REGION DURING THE OVERNIGHT HOURS. MOST OF THE CEILINGS SHOULD REMAIN VFR BUT KGTF/KHLN/KBZN MAY SEE BRIEF PERIODS OF MVFR IF MODERATE SHOWERS DEVELOP NEAR THOSE TERMINALS. WINDS WILL GENERALLY BE LIGHT TONIGHT BUT WILL INCREASE TOWARD MORNING VCNTY KGTF/KCTB FOLLOWING FRONTAL PASSAGE...EXPECT GUSTS OF 20-30 KTS. WARANAUSKAS && .PREV DISCUSSION... /ISSUED 610 PM MDT THU SEP 15 2011/ TONIGHT THROUGH SATURDAY...AFTER AN EXTENDED PERIOD OF QUIET WEATHER EXPECT A COUPLE OF DAYS OF UNSETTLED WEATHER. ONE UPPER TROUGH WILL BE MOVING THROUGH THE AREA ON FRIDAY WHILE A SECOND UPPER TROUGH IS FORECAST TO MOVE INTO THE AREA ON SATURDAY. THE BEST THREAT FOR PRECIPITATION DURING THE PERIOD WILL BE OVER SOUTHWEST MONTANA FRIDAY MORNING AS A COLD FRONT AHEAD OF THE FIRST UPPER TROUGH MOVES THROUGH THE AREA. THERE APPEARS TO BE ENOUGH MOISTURE AND LIFT THAT MOST LOCATIONS OVER SOUTHWEST MONTANA WILL SEE MEASURABLE RAINFALL. A DRIER AIRMASS WILL SPREAD EAST OVER THE PLAINS ON FRIDAY BEHIND THE COLD FRONT BUT MOISTURE WILL LINGER OVER SOUTHWEST MONTANA INTO FRIDAY NIGHT. THE UPPER TROUGH ON SATURDAY IS NOT EXPECTED TO HAVE AS MUCH MOISTURE WITH IT OVER SOUTHWEST MONTANA AS THE FIRST UPPER TROUGH SO WILL GO WITH JUST A CHANCE OF PRECIPITATION. I WAS NOT SURE WHAT TO DO WITH THE CHANCE OF RAIN FORECAST OVER THE PLAINS ON SATURDAY AS THERE WILL BE DOWNSLOPE WINDS BUT ALSO THE POSSIBILITY OF WEAK INSTABILITY. I DECIDED TO GO WITH A SLIGHT CHANCE OF SHOWERS. BLANK SATURDAY NIGHT THROUGH THURSDAY...AN UPPER LEVEL LOW PRESSURE TROUGH WILL BE MOVING EAST OF THE ZONES SATURDAY NIGHT. THIS WILL LEAVE THE AIRMASS COOLER THAN THE PREVIOUS SEVERAL DAYS AND TEMPERATURES WILL REMAIN NEAR NORMALS. HIGH PRESSURE WILL BUILD OVER THE ZONES THROUGH SUNDAY WHILE...TO THE WEST...THE NEXT SHORTWAVE WILL BE MOVING THROUGH THE PACIFIC NORTHWEST. THE CHANCE FOR SHOWERS WILL INCREASE MONDAY AS THIS SYSTEM CROSSES THE ROCKIES. WINDS WILL ALSO INCREASE AHEAD OF THE SYSTEM AND MONDAY AFTERNOON SHOULD BE QUITE BREEZY. THE SHORTWAVE RAPIDLY MOVES EAST OF THE ZONES MONDAY NIGHT...OVERALL...RAINFALL TOTALS WILL REMAIN LOW. HIGH PRESSURE WILL BUILD AGAIN ON TUESDAY AND REMAIN THE DOMINANT FEATURE THROUGH THURSDAY. TEMPERATURES WILL TREND UPWARDS THROUGH THURSDAY ALTHOUGH CLEAR SKIES AND DRY CONDITIONS WILL ALLOW FOR COOL MORNING TEMPERATURES. ZELZER && .PRELIMINARY POINT TEMPS/POPS... GTF 51 72 42 69 / 20 40 10 20 CTB 47 70 39 66 / 50 10 10 20 HLN 50 69 42 69 / 40 60 20 20 BZN 45 68 38 69 / 20 60 30 30 WEY 33 59 29 59 / 10 70 60 40 DLN 45 64 38 66 / 30 70 40 20 HVR 49 73 39 72 / 20 20 10 20 LWT 46 66 40 68 / 10 40 20 20 && .TFX WATCHES/WARNINGS/ADVISORIES... NONE. && SHORT TERM...SUK LONG TERM... AVIATION...WARANAUSKAS WEATHER.GOV/GREATFALLS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GREAT FALLS MT 341 AM MDT THU SEP 15 2011 MTZ008>015-044>055-160945- BEAVERHEAD-NORTHERN ROCKY MOUNTAIN FRONT-EASTERN GLACIER-HILL- CASCADE-CHOUTEAU-CENTRAL AND SOUTHERN LEWIS AND CLARK-MADISON- TOOLE-LIBERTY-EASTERN PONDERA-BLAINE- SOUTHERN ROCKY MOUNTAIN FRONT-EASTERN TETON-JUDITH BASIN-FERGUS- JEFFERSON-BROADWATER-MEAGHER-GALLATIN- 341 AM MDT THU SEP 15 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...FRIDAY THROUGH WEDNESDAY THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.
3 high wind. Local standard time, as filed.
A wind gust to 79 mph was reported at Saint Mary 13W (the Logan Pass Visitor Center in Glacier National Park).
A wind gust to 67 mph was reported at Saint Mary 13W (the Logan Pass Visitor Center in Glacier National Park).
A wind gust to 58 mph was reported at saint Mary 13W (the Logan Pass Visitor Center in Glacier National Park).
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, September 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: 346378, 346377, 346376.