Low surface pressure across southern Canada contributed to a tight gradient and high winds across the Northern Rocky Mountain Front and Eastern Glacier County. 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.
Low surface pressure across southern Canada contributed to a tight gradient and high winds across the Northern Rocky Mountain Front and Eastern Glacier County. 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 Jul 8, 2:41 AM MST, 1 hour 19 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREAT FALLS MT 341 AM MDT FRI JUL 8 2011 .DISCUSSION... TODAY THROUGH SUNDAY...AN UPPER LEVEL LOW PRESSURE TROF IS OVER THE IDAHO PANHANDLE AND THE ASSOCIATED COLD FRONT WILL KEEP MAX TEMPS CLOSER TO NORMALS. STRONG WINDS WILL ALSO BE A FACTOR AS THE LOW PRESSURE TROF MOVES ACROSS THE ROCKIES...AND A HIGH WIND WARNING WILL REMAIN IN EFFECT UNTIL SATURDAY MORNING ACROSS THE ROCKIES AND EASTERN GLACIER COUNTY. THE BROAD TROF WILL MOVE EAST AND HEIGHTS ALOFT WILL BEGIN TO RISE BY SATURDAY EVENING. THE AIRMASS WILL REMAIN QUITE DRY THROUGH SUNDAY WITH THE EXCEPTION OF THE THE SOUTHWEST ZONES. A CHANCE OF THUNDERSTORMS WILL DEVELOP SUNDAY AFTERNOON AS MONSOONAL MOISTURE MOVES NORTH INTO THE ZONES. THIS WILL DESTABILIZE THE AIRMASS AND A SERIES OF WEAK DISTURBANCES WILL HELP KEEP THE REGION UNSETTLED. ZELZER SUNDAY NIGHT THROUGH FRIDAY...OVERALL A TYPICAL JULY WEATHER PATTERN SETTING UP OVER THE REGION DURING THIS PERIOD. BOTH THE EC/GFS HAVE A SLIGHT DIFFERENCE IN BOTH THE TIMING AND STRENGTH OF SHORTWAVE ENERGY MOVING THROUGH THE REGION DURING THIS PERIOD. THUS THERE IS A CHANCE FOR ISOLATED/SCATTERED THUNDERSTORMS ACROSS THE REGION THROUGH THE PERIOD. OF COURSE...THE BEST TIMEFRAME FOR THE THUNDERSTORM ACTIVITY TO OCCUR WILL BE DURING THE AFTERNOON/EVENING HOURS. A BRIEF PERIOD OF HEAVY RAIN WILL BE POSSIBLE FROM THE STRONGER STORMS...BUT FOR NOW...NO WIDESPREAD HEAVY RAINFALL IS EXPECTED NEXT WEEK. IN TERMS OF TEMPERATURES...JULY LIKE TEMPERATURES CAN BE EXPECTED...WITH AFTERNOON TEMPERATURES GENERALLY AVERAGING NEAR TO SLIGHTLY ABOVE NORMAL READINGS FOR MOST DAYS. BRUSDA && .AVIATION... UPDATED 0500Z. ISOLATED SHOWERS AND THUNDERSTORMS WILL LINGER OVER PORTIONS OF CENTRAL AND NORTH CENTRAL MONTANA TONIGHT. OBSCURATION OF MOUNTAINS IS LIKELY AT TIMES IN THESE SHOWERS. A COLD FRONT WILL MOVE ACROSS THE REGION OVERNIGHT CLEARING THINGS OUT FOR FRIDAY. WESTERLY SURFACE WINDS TOMORROW WILL BE BREEZY IN MOST LOCATIONS AND WILL BECOME GUSTY...UP TO 50 KNOTS...ACROSS THE ROCKY MOUNTAIN FRONT AND PLAINS OF NORTH CENTRAL MONTANA. && .HYDROLOGY... RESERVOIRS ACROSS THE AREA REMAIN NEAR CAPACITY WITH UNUSUALLY HIGH OUTFLOWS. TEMPERATURES WILL BE A LITTLE COOLER FRIDAY AND SATURDAY WHICH WILL SLOW SNOWMELT. HOWEVER SNOW MELT WILL INCREASE NEXT WEEK AS TEMPERATURES BECOME VERY WARM. NO MORE THAN SCATTERED SHOWERS AND THUNDERSTORMS ARE FORECAST INTO EARLY NEXT WEEK. MANY RIVERS AND STREAMS ARE RUNNING HIGH AND ANY ADDITIONAL WATER TO THEM COULD CAUSE THEM TO BECOME BANKFULL OR EVEN GO OUT OF THEIR BANKS. && .PRELIMINARY POINT TEMPS/POPS... GTF 78 45 78 47 / 10 0 0 0 CTB 71 44 72 44 / 10 0 0 0 HLN 79 48 80 50 / 10 0 0 0 BZN 84 44 82 45 / 10 0 0 0 WEY 74 36 73 38 / 20 10 0 0 DLN 80 43 80 45 / 10 0 0 0 HVR 79 47 79 46 / 20 0 0 0 LWT 78 44 76 46 / 20 0 0 10 && .TFX WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING UNTIL 6 AM MDT SATURDAY EASTERN GLACIER... NORTHERN ROCKY MOUNTAIN FRONT. FLOOD HIGHLIGHTS REMAIN IN EFFECT FOR PORTIONS OF THE AREA UNTIL FURTHER NOTICE. && WEATHER.GOV/GREATFALLS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GREAT FALLS MT 420 PM MDT THU JUL 7 2011 MTZ012-015-055-082230- CASCADE-MADISON-GALLATIN- 420 PM MDT THU JUL 7 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL MONTANA AND SOUTHWEST MONTANA. .DAY ONE...TONIGHT FLOOD HIGHLIGHTS REMAIN IN EFFECT ACROSS PORTIONS OF THE REGION. SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON AND EVENING WITH SOME STORMS BECOMING STRONG TO SEVERE...PRODUCING LARGE HAIL AND GUSTY WINDS. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY FLOOD HIGHLIGHTS WILL REMAIN IN EFFECT ACROSS PORTIONS OF THE REGION UNTIL FURTHER NOTICE. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED THIS EVENING FOR THE THUNDERSTORM ACTIVITY. PLEASE RELAY ANY REPORTS OF HAIL...STRONG WINDS...OR FLASH FLOODING TO THE NATIONAL WEATHER SERVICE OFFICE IN GREAT FALLS. MTZ008-013-047-050>054-082230- BEAVERHEAD-CHOUTEAU-BLAINE-JUDITH BASIN-FERGUS-JEFFERSON- BROADWATER-MEAGHER- 420 PM MDT THU JUL 7 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL MONTANA...NORTH CENTRAL MONTANA AND SOUTHWEST MONTANA. .DAY ONE...TONIGHT SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON AND EVENING WITH SOME STORMS BECOMING STRONG TO SEVERE...PRODUCING LARGE HAIL...HEAVY RAINFALL AND GUSTY WINDS. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED THIS EVENING FOR THE THUNDERSTORM ACTIVITY. PLEASE RELAY ANY REPORTS OF HAIL...STRONG WINDS OR FLASH FLOODING TO THE NATIONAL WEATHER SERVICE OFFICE IN GREAT FALLS. MTZ009-010-082230- NORTHERN ROCKY MOUNTAIN FRONT-EASTERN GLACIER- 420 PM MDT THU JUL 7 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL MONTANA. .DAY ONE...TONIGHT SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON AND EVENING. SOME STORMS MAY PRODUCE BRIEF HEAVY RAINFALL AND SMALL HAIL. A HIGH WIND WARNING IS IN EFFECT BEGINNING AT MIDNIGHT. WESTERLY WINDS OF 30 TO 50 MPH WITH GUSTS TO 60 TO 70 MPH WILL BE POSSIBLE DURING THE OVERNIGHT HOURS. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY THE HIGH WIND WARNING CONTINUES UNTIL SATURDAY MORNING. .SPOTTER INFORMATION STATEMENT... PLEASE RELAY ANY REPORTS OF HAIL...STRONG WINDS OR FLASH FLOODING TO THE NATIONAL WEATHER SERVICE OFFICE IN GREAT FALLS. MTZ014-046-048-049-082230- CENTRAL AND SOUTHERN LEWIS AND CLARK-EASTERN PONDERA- SOUTHERN ROCKY MOUNTAIN FRONT-EASTERN TETON- 420 PM MDT THU JUL 7 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL MONTANA AND SOUTHWEST MONTANA. .DAY ONE...TONIGHT ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTERNOON AND EVENING. SOME STORMS MAY PRODUCE BRIEF HEAVY RAINFALL AND SMALL HAIL. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW. .SPOTTER INFORMATION STATEMENT... PLEASE RELAY ANY REPORTS OF HAIL...STRONG WINDS OR FLASH FLOODING TO THE NATIONAL WEATHER SERVICE OFFICE IN GREAT FALLS. MTZ011-044-045-082230- HILL-TOOLE-LIBERTY- 420 PM MDT THU JUL 7 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL MONTANA. .DAY ONE...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.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
145 AM MDT FRI JUL 08 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0900 PM NON-TSTM WND GST 8 SE EAST GLACIER PARK 48.37N 113.10W
07/07/2011 M55 MPH GLACIER MT MESONET
55 MPH WIND GUST AT THE DEEP CREEK RAWS. THIS WIND GUST
WAS ALONG A COOL FRONT...BUT NEAREST LIGHTNING DETECTED
WAS 20 MILES TO THE NORTH.
&&
BRUSDAPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
147 AM MDT FRI JUL 08 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0934 PM NON-TSTM WND GST 3 SW CUT BANK 48.61N 112.38W
07/07/2011 M46 MPH GLACIER MT ASOS
46 MPH PEAK WIND GUST AT THE CUT BANK AIRPORT. THIS
WIND GUST WAS ALONG A COOL FRONT...BUT NO LIGHTNING
DETECTED NEARBY.
&&
BRUSDAPRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE GREAT FALLS MT
148 AM MDT FRI JUL 08 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0831 AM HAIL 7 W FORESTGROVE 47.01N 109.23W
07/07/2011 E0.50 INCH FERGUS MT TRAINED SPOTTER
HAIL QUARTER TO HALF INCH IN DIAMETER AND HEAVY RAIN.
0938 AM HAIL 22 E ROY 47.34N 108.50W
07/07/2011 M1.00 INCH FERGUS MT TRAINED SPOTTER
QUARTER SIZED HAIL AND WIND GUSTS ESTIMATED AT 30 MPH.
0938 AM HAIL 22 E ROY 47.33N 108.49W
07/07/2011 M1.00 INCH FERGUS MT TRAINED SPOTTER
QUARTER SIZED HAIL AND GUSTY WINDS.
0938 AM HAIL 22 E ROY 47.34N 108.50W
07/07/2011 M1.75 INCH FERGUS MT TRAINED SPOTTER
HAIL UP TO THE SIZE OF GOLF BALLS COVERING THE GROUND.
FRONT WINDSHIELD BROKEN OUT OF A TRUCK. 0.24 INCHES OF
RAINFALL.
1210 PM HAIL 2 ENE UTICA 46.98N 110.05W
07/07/2011 M0.50 INCH JUDITH BASIN MT TRAINED SPOTTER
LITTLE WIND. 0.06 OF AN INCH RAIN FELL. HAIL SIZE UP TO
1 2 INCH.
0100 PM HAIL 6 S MOORE 46.89N 109.69W
07/07/2011 E0.25 INCH FERGUS MT TRAINED SPOTTER
BREIF HEAVY RAINFALL
0330 PM HEAVY RAIN 2 N GARNEILL 46.78N 109.75W
07/07/2011 E0.50 INCH FERGUS MT TRAINED SPOTTER
A HALF INCH RAIN FELL IN ABOUT A 30 MIN PERIOD. NO HAIL
NOR STRONG WINDS.
0358 PM HAIL CHINOOK 48.59N 109.23W
07/07/2011 E0.25 INCH BLAINE MT PUBLIC
HEAVY RAIN FELL FOR 5 MIN. PEA SIZED HAIL.
0500 PM FLASH FLOOD 5 E GARNEILL 46.75N 109.66W
07/07/2011 FERGUS MT PUBLIC
.75 INCHES RAIN IN 15 MINUTES WITH TOTAL OF 1.5 INCHES
THROUGH 5PM MEASURED BY PERSONAL WEATHER STATION. WATER
OVER COUNTY ROAD. PEA SIZE HAIL AT TIMES WITH LITTLE OR
NO WIND.
0900 PM NON-TSTM WND GST 8 SE EAST GLACIER PARK 48.37N 113.10W
07/07/2011 M55 MPH GLACIER MT MESONET
55 MPH WIND GUST AT THE DEEP CREEK RAWS. THIS WIND GUST
WAS ALONG A COOL FRONT...BUT NEAREST LIGHTNING DETECTED
WAS 20 MILES TO THE NORTH.
0934 PM NON-TSTM WND GST 3 SW CUT BANK 48.61N 112.38W
07/07/2011 M46 MPH GLACIER MT ASOS
46 MPH PEAK WIND GUST AT THE CUT BANK AIRPORT. THIS
WIND GUST WAS ALONG A COOL FRONT...BUT NO LIGHTNING
DETECTED NEARBY.
1100 PM TSTM WND GST 13 S FORT BELKNAP 48.30N 108.72W
07/07/2011 M48 MPH BLAINE MT MESONET
48 MPH PEAK WIND GUST AT THE FORT BELKNAP RAWS
LOCATION. TIME OF EVENT IS ESTIMATED.
&&
BRUSDAPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
312 AM MDT FRI JUL 08 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0300 AM NON-TSTM WND GST 12 NE BABB 48.98N 113.25W
07/08/2011 M52 MPH GLACIER MT TRAINED SPOTTER
52 MPH PEAK WIND GUST AT THE PORT OF PIEGAN.
&&
BRUSDAPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
323 AM MDT FRI JUL 08 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0300 AM NON-TSTM WND GST 1 E EAST GLACIER PARK 48.45N 113.19W
07/08/2011 M48 MPH GLACIER MT DEPT OF HIGHWAYS
48 MPH PEAK WIND GUST AT THE DOT SENSOR JUST EAST OF
EAST GLACIER PARK.
&&
BRUSDAPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
408 AM MDT FRI JUL 08 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0321 AM NON-TSTM WND GST 8 SE EAST GLACIER PARK 48.37N 113.10W
07/08/2011 M60 MPH GLACIER MT MESONET
&&
CZ4 high wind. Local standard time, as filed.
A wind gust to 70 mph was reported at East Glacier Park 8SE (the Deep Creek RAWS site).
A wind gust to 58 mph was reported at the Cut Bank ASOS site.
A wind gust to 58 mph was reported at Pendroy 2NW (the Pendroy DOT site).
A wind gust to 60 mph was reported at Browning.
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, July 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: 333336, 333338, 333340, 333337.