Generally dry thunderstorms developed along the Rocky Mountain Front during the afternoon hours of the 19th. These storms produced wind gusts in excess of 60 mph.
Every event with a place to put it. Tap one for its entry below.
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.
Generally dry thunderstorms developed along the Rocky Mountain Front during the afternoon hours of the 19th. These storms produced wind gusts in excess of 60 mph.
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 Aug 19, 2:00 PM MST, 2 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREAT FALLS MT 300 PM MDT SUN AUG 19 2007 .DISCUSSION... ANOTHER ACTIVE EVENING OF WEATHER EXPECTED...BEFORE COOLER AND A BIT MORE STABLE AIR MOVES INTO THE REGION FOR MONDAY AND TUESDAY. A PACIFIC COLD FRONT IS APPROACHING THE ROCKY MOUNTAIN FRONT AT 3 PM THIS AFTERNOON...AND THIS FRONT WILL MOVE EASTWARD ACROSS NORTH CENTRAL AND SOUTHWEST MONTANA THROUGH THE REMAINDER OF THE AFTERNOON AND EVENING HOURS. EXPECT A LINE OF THUNDERSTORMS TO ACCOMPANY THE FRONTAL PASSAGE. SOME STORMS COULD PRODUCE DAMAGING WIND GUSTS OR LARGE HAIL. EXPECT COOLER AIR TO MOVE INTO THE REGION AFTER MIDNIGHT. FOR MONDAY AND TUESDAY...AN UPPER LEVEL TROF OF LOW PRESSURE WILL RESIDE OVER THE REGION FOR BOTH MONDAY AND TUESDAY. THIS WILL RESULT IN COOLER AIR MOVING INTO THE REGION...WITH TEMPERATURES ONLY NEAR NORMAL FOR EARLY NEXT WEEK. THE CHANCES FOR ANY PRECIPITATION WILL BE ON THE LOW SIDE...WITH THE BEST CHANCE FOR ANY PRECIP OVER THE MOUNTAINS. WINDS WILL REMAIN BREEZY...ESPECIALLY ON MONDAY...BUT WITH THE COOLER TEMPERATURES HUMIDITIES WILL NOT BE AS LOW AS THEY HAVE BEEN...THUS A RED FLAG WARNING IS NOT EXPECTED AT THIS TIME. BRUSDA TUESDAY NIGHT THROUGH FRIDAY NIGHT...UPPER LEVEL LOW MOVES TO THE EAST OF MONTANA PUTTING CWA IN A NORTHWEST FLOW ALOFT THEN SWITCHES TO A WESTERLY FLOW FOR THE PERIOD. A DISTURBANCE MOVES THROUGH THE FLOW ON THURSDAY FOR A CHANCE OF SHOWERS AND THUNDERSTORMS. TEMPERATURES WILL BE NEAR NORMAL. MODELS TRY TO WARM TEMPERATURES UP SOME EACH DAY BUT FOR NOW WILL GO WITH MODERATION AS NOTHING INDICATES A FAST WARMING TREND. CAMP SATURDAY THROUGH SUNDAY...MODELS ARE IN FAIR AGREEMENT DURING THIS PERIOD. AN UPPER LEVEL RIDGE BUILDS OVER THE REGION RESULTING IN A DRY AND WARMER FORECAST. SKIES WILL BE CLEAR TO PARTLY CLOUDY. TEMPERATURES ARE EXPECTED TO WARM TO SEVERAL DEGREES ABOVE SEASONAL AVERAGES. EK && .AVIATION... UPDATED 1755Z. A STRONG UPPER LEVEL TROF AND ASSOCIATED SURFACE LOW AND COLD FRONT WILL MOVE EAST ACROSS THE REGION LATE THIS AFTERNOON AND TONIGHT. GUSTY SOUTHWEST WINDS WILL DEVELOP BY EARLY THIS AFTERNOON AHEAD OF THE FRONT WITH WINDS SHIFTING TO THE WEST AND REMAINING WINDY BEHIND THE FRONT. THE N-S COULD FRONT WILL CROSS THE CONTINENTAL DIVIDE BETWEEN 20 AND 23Z AND REACH A KLWT TO KHVR LINE BETWEEN 02 AND 05Z. EXPECT SCATTERED THUNDERSTORMS TO DEVELOP AHEAD OF THE FRONT LATER THIS AFTERNOON WITH ANY THUNDERSTORM ACTIVITY HAVING THE POTENTIAL FOR STRONG GUSTY WINDS. WESTERLY WINDS WILL DIMINISH SLIGHTLY AFTER 06Z BUT REMAIN GUSTY...ESPECIALLY ALONG THE ROCKY MOUNTAIN FRONT AND ADJACENT PLAINS. HOENISCH && .FIRE WEATHER... A RED FLAG WARNING WILL CONTINUE THROUGH MIDNIGHT...AS A PACIFIC COLD FRONT MOVES THROUGH THE REGION. EXPECT GUSTY SOUTH WINDS AHEAD OF THE FRONT...TO SWITCH TO THE WEST BEHIND THE FRONT. THE WINDS WILL REMAIN STRONG AT HIGHER ELEVATIONS THROUGH MONDAY. HUMIDITIES WILL FALL TO NEAR 10 PERCENT BY LATE AFTERNOON...THEN BEGIN TO INCREASE AFTER FRONTAGE PASSAGE. BREEZY CONDITIONS WITH A BIT HIGHER HUMIDITIES ARE EXPECTED FOR MONDAY. BRUSDA && .PRELIMINARY POINT TEMPS/POPS... GTF 53 76 48 75 / 20 10 10 10 CTB 50 72 45 71 / 20 10 10 10 HLN 54 78 52 77 / 20 10 10 10 BZN 49 79 46 78 / 30 10 10 10 WEY 38 70 41 72 / 40 20 20 10 DLN 46 75 46 74 / 20 10 10 10 HVR 57 77 49 76 / 50 10 10 10 LWT 53 73 47 72 / 50 10 10 10 && .TFX WATCHES/WARNINGS/ADVISORIES... RED FLAG WARNING UNTIL MIDNIGHT MDT TONIGHT FOR MTZ112>118. SEVERE THUNDERSTORM WATCH UNTIL 8 PM MDT THIS EVENING FOR MTZ008- 011>015-047-050>055. && SHORT TERM...99 LONG TERM...99 AVIATION...99 WEATHER.GOV/GREATFALLS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GREAT FALLS MT 643 AM MDT SUN AUG 19 2007 MTZ011-013-047-050-051-054-055-201245- HILL-CHOUTEAU-BLAINE-JUDITH BASIN-FERGUS-MEAGHER-GALLATIN- 643 AM MDT SUN AUG 19 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL MONTANA...NORTH CENTRAL MONTANA AND SOUTHWEST MONTANA. .DAY ONE...TODAY AND TONIGHT A COLD FRONT WILL MOVE THROUGH WESTERN AND CENTRAL MONTANA TODAY AND TONIGHT. VERY BREEZY AND GUSTY SOUTHERLY WINDS AHEAD OF THE FRONT WILL BECOME WESTERLY LATER THIS AFTERNOON AND TONIGHT. RELATIVE HUMIDITIES WILL ALSO BECOME LOW AGAIN THIS AFTERNOON AND EVENING. THE COMBINATION OF DRY AND WINDY WEATHER WILL CAUSE DANGEROUS FIRE WEATHER CONDITIONS. THEREFORE...THE RED FLAG WARNING REMAINS IN EFFECT FOR NORTH CENTRAL AND SOUTHWEST MONTANA FROM NOON MDT TODAY THROUGH MIDNIGHT MDT TONIGHT. SCATTERED SHOWERS AND THUNDERSTORMS WILL ALSO DEVELOP ACROSS THE AREA THIS AFTERNOON. SOME OF THESE STORMS MAY PRODUCE HAIL AND DAMAGING WINDS...WHICH WOULD ADD TO THE HAZARDOUS FIRE WEATHER CONDITIONS. STORMS AND WINDS WILL DECREASE OVERNIGHT...WITH GOOD RELATIVE HUMIDITY RECOVERY. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER MONDAY THROUGH SATURDAY IS LOW. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ008>010-012-014-015-044>046-048-049-052-053-201245- BEAVERHEAD-NORTHERN ROCKY MOUNTAIN FRONT-EASTERN GLACIER-CASCADE- CENTRAL AND SOUTHERN LEWIS AND CLARK-MADISON-TOOLE-LIBERTY- EASTERN PONDERA-SOUTHERN ROCKY MOUNTAIN FRONT-EASTERN TETON- JEFFERSON-BROADWATER- 643 AM MDT SUN AUG 19 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL MONTANA...NORTH CENTRAL MONTANA AND SOUTHWEST MONTANA. .DAY ONE...TODAY AND TONIGHT A COLD FRONT WILL MOVE THROUGH WESTERN AND CENTRAL MONTANA TODAY AND TONIGHT. VERY BREEZY AND GUSTY SOUTHERLY WINDS AHEAD OF THE FRONT WILL BECOME WESTERLY LATER THIS AFTERNOON AND TONIGHT. RELATIVE HUMIDITIES WILL ALSO BECOME LOW AGAIN THIS AFTERNOON AND EVENING. THE COMBINATION OF DRY AND WINDY WEATHER WILL CAUSE DANGEROUS FIRE WEATHER CONDITIONS. THEREFORE...THE RED FLAG WARNING REMAINS IN EFFECT FOR NORTH CENTRAL AND SOUTHWEST MONTANA FROM NOON MDT TODAY THROUGH MIDNIGHT MDT TONIGHT. ISOLATED SHOWERS AND THUNDERSTORMS WILL ALSO DEVELOP ACROSS THE AREA THIS AFTERNOON. GUSTY AND ERRATIC WINDS WITH THESE STORMS WOULD ADD TO THE HAZARDOUS FIRE WEATHER CONDITIONS. STORMS AND WINDS WILL DECREASE OVERNIGHT...WITH GOOD RELATIVE HUMIDITY RECOVERY. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER MONDAY THROUGH SATURDAY IS LOW. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE GREAT FALLS MT
1102 AM MDT SUN AUG 19 2007
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0257 PM HAIL 2 N DILLON 45.24N 112.63W
08/18/2007 M0.25 INCH BEAVERHEAD MT TRAINED SPOTTER
WINDS GUSTING TO 35 MILES AN HOUR.
0258 PM HAIL 3 N DILLON 45.26N 112.63W
08/18/2007 E1.00 INCH BEAVERHEAD MT TRAINED SPOTTER
BREIF HEAVY RAIN 0.61 INCHES MEASURED.
0258 PM HAIL DILLON 45.22N 112.63W
08/18/2007 E0.88 INCH BEAVERHEAD MT TRAINED SPOTTER
BREIF HEAVY RAIN FILLED STREETS UP TO AND OVER SOME
CURBS.
0355 PM TSTM WND DMG 2 W VIRGINIA CITY 45.30N 111.98W
08/18/2007 MADISON MT LAW ENFORCEMENT
*** 1 INJ *** A THUNDERSTORM WIND GUST BLEW OFF A SIGN 2
FEET BY 2 FEET...AND THROUGH THE WINDSHIELD OF AN
ON-COMING CAR...CAUSING INJURY TO THE DRIVER. MARBLE SIZE
HAIL WAS LYING ON THE GROUND WHEN POLICE ARRIVED.
0425 PM HAIL 3 N DILLON 45.26N 112.63W
08/18/2007 E0.88 INCH BEAVERHEAD MT TRAINED SPOTTER
0455 PM TSTM WND GST 2 W PENDROY 48.06N 112.34W
08/18/2007 M56.00 MPH TETON MT DEPT OF HIGHWAYS
56 MPH PEAK WIND GUST AT THE PENDROY DOT LOCATION.
0615 PM HAIL 12 W WHITEHALL 45.87N 112.35W
08/18/2007 E0.88 INCH JEFFERSON MT TRAINED SPOTTER
A MIX OF HAIL SIZES FROM PEA TO NICKLE WITH BRIEF HEAVY
RAIN.
&&
HERE IS A SUMMARY OF SEVERE WEATHER REPORTS RECIEVED FOR SATURDAY
AUGUST 18TH.
BRUSDAPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1115 AM MDT SUN AUG 19 2007
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0500 PM HAIL MCALLISTER 45.44N 111.73W
08/18/2007 M1.25 INCH MADISON MT TRAINED SPOTTER
1.25 INCH HAIL...HALF DOLLAR SIZE...FELL IN THE CITY OF
MCALLISTER.
&&
BRUSDAPRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE GREAT FALLS MT
1121 AM MDT SUN AUG 19 2007
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0257 PM HAIL 2 N DILLON 45.24N 112.63W
08/18/2007 M0.25 INCH BEAVERHEAD MT TRAINED SPOTTER
WINDS GUSTING TO 35 MILES AN HOUR.
0258 PM HAIL 3 N DILLON 45.26N 112.63W
08/18/2007 E1.00 INCH BEAVERHEAD MT TRAINED SPOTTER
BREIF HEAVY RAIN 0.61 INCHES MEASURED.
0258 PM HAIL DILLON 45.22N 112.63W
08/18/2007 E0.88 INCH BEAVERHEAD MT TRAINED SPOTTER
BREIF HEAVY RAIN FILLED STREETS UP TO AND OVER SOME
CURBS.
0355 PM TSTM WND DMG 2 W VIRGINIA CITY 45.30N 111.98W
08/18/2007 MADISON MT LAW ENFORCEMENT
*** 1 INJ *** A THUNDERSTORM WIND GUST BLEW OFF A SIGN 2
FEET BY 2 FEET...AND THROUGH THE WINDSHIELD OF AN
ON-COMING CAR...CAUSING INJURY TO THE DRIVER. MARBLE SIZE
HAIL WAS LYING ON THE GROUND WHEN POLICE ARRIVED.
0425 PM HAIL 3 N DILLON 45.26N 112.63W
08/18/2007 E0.88 INCH BEAVERHEAD MT TRAINED SPOTTER
0455 PM TSTM WND GST 2 W PENDROY 48.06N 112.34W
08/18/2007 M56.00 MPH TETON MT DEPT OF HIGHWAYS
56 MPH PEAK WIND GUST AT THE PENDROY DOT LOCATION.
0500 PM HAIL MCALLISTER 45.44N 111.73W
08/18/2007 M1.25 INCH MADISON MT TRAINED SPOTTER
1.25 INCH HAIL...HALF DOLLAR SIZE...FELL IN THE CITY OF
MCALLISTER.
0615 PM HAIL 12 W WHITEHALL 45.87N 112.35W
08/18/2007 E0.88 INCH JEFFERSON MT TRAINED SPOTTER
A MIX OF HAIL SIZES FROM PEA TO NICKLE WITH BRIEF HEAVY
RAIN.
&&
HERE IS A SUMMARY OF SEVERE WEATHER REPORTS RECIEVED FOR SATURDAY
AUGUST 18TH.
BRUSDAPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
1152 AM MDT SUN AUG 19 2007
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0355 PM HAIL 2 W VIRGINIA CITY 45.30N 111.98W
08/18/2007 E0.88 INCH MADISON MT PUBLIC
NICKEL SIZE HAIL FELL IN NEVADA CITY...CAUSING DAMAGE TO
30 WINDOWS. SOME MINOR BRUISES TO PASSENGERS TRAVELING ON
AN OPEN CAR TRAIN BETWEEN NEVADA CITY AND VIRGINIA CITY.
SOME TREE DAMAGE...WITH WIND SPEEDS ESTIMATED BETWEEN 50
AND 60 MPH.
&&
BRUSDAPRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE GREAT FALLS MT
1155 AM MDT SUN AUG 19 2007
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0257 PM HAIL 2 N DILLON 45.24N 112.63W
08/18/2007 M0.25 INCH BEAVERHEAD MT TRAINED SPOTTER
WINDS GUSTING TO 35 MILES AN HOUR.
0258 PM HAIL 3 N DILLON 45.26N 112.63W
08/18/2007 E1.00 INCH BEAVERHEAD MT TRAINED SPOTTER
BREIF HEAVY RAIN 0.61 INCHES MEASURED.
0258 PM HAIL DILLON 45.22N 112.63W
08/18/2007 E0.88 INCH BEAVERHEAD MT TRAINED SPOTTER
BREIF HEAVY RAIN FILLED STREETS UP TO AND OVER SOME
CURBS.
0355 PM TSTM WND DMG 2 W VIRGINIA CITY 45.30N 111.98W
08/18/2007 MADISON MT LAW ENFORCEMENT
*** 1 INJ *** A THUNDERSTORM WIND GUST BLEW OFF A SIGN 2
FEET BY 2 FEET...AND THROUGH THE WINDSHIELD OF AN
ON-COMING CAR...CAUSING INJURY TO THE DRIVER. MARBLE SIZE
HAIL WAS LYING ON THE GROUND WHEN POLICE ARRIVED.
0355 PM HAIL 2 W VIRGINIA CITY 45.30N 111.98W
08/18/2007 E0.88 INCH MADISON MT PUBLIC
NICKEL SIZE HAIL FELL IN NEVADA CITY...CAUSING DAMAGE TO
30 WINDOWS. SOME MINOR BRUISES TO PASSENGERS TRAVELING ON
AN OPEN CAR TRAIN BETWEEN NEVADA CITY AND VIRGINIA CITY.
SOME TREE DAMAGE...WITH WIND SPEEDS ESTIMATED BETWEEN 50
AND 60 MPH.
0425 PM HAIL 3 N DILLON 45.26N 112.63W
08/18/2007 E0.88 INCH BEAVERHEAD MT TRAINED SPOTTER
0455 PM TSTM WND GST 2 W PENDROY 48.06N 112.34W
08/18/2007 M56.00 MPH TETON MT DEPT OF HIGHWAYS
56 MPH PEAK WIND GUST AT THE PENDROY DOT LOCATION.
0500 PM HAIL MCALLISTER 45.44N 111.73W
08/18/2007 M1.25 INCH MADISON MT TRAINED SPOTTER
1.25 INCH HAIL...HALF DOLLAR SIZE...FELL IN THE CITY OF
MCALLISTER.
0615 PM HAIL 12 W WHITEHALL 45.87N 112.35W
08/18/2007 E0.88 INCH JEFFERSON MT TRAINED SPOTTER
A MIX OF HAIL SIZES FROM PEA TO NICKEL WITH BRIEF HEAVY
RAIN.
&&
HERE IS A SUMMARY OF SEVERE WEATHER REPORTS RECIEVED FOR SATURDAY
AUGUST 18TH.
BRUSDAPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
301 PM MDT SUN AUG 19 2007
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0250 PM HAIL 2 E SILVER CITY 46.76N 112.13W
08/19/2007 E0.50 INCH LEWIS AND CLARK MT TRAINED SPOTTER
PEA AND MARBLE SIZE HAIL WITH A WIND GUST MEASURED AT 52
MILES AN HOUR.
&&
SAUCIERThe Great Falls radar (KTFX), 84 km away, was scanning. The volume nearest the first event began at 21:02 UTC.
10 thunderstorm wind. Local standard time, as filed.
A severe thunderstorm produced a wind gust to 60 mph at Wolf Creek 9S (Sieben Flats DOT site).
A severe thunderstorm produced a wind gust to 58 mph at the Helena airport.
A severe thunderstorm produced a wind gust to 59 mph at Wolf Creek 8N (the Gary Cooper Bridge DOT site).
A severe thunderstorm produced a wind gust to 62 mph at Great Falls 3SW.
A severe thunderstorm produced a wind gust to 58 mph at Malmstrom Air Force Base (Great Falls 6E).
A severe thunderstorm produced a wind gust to 58 mph at Brady 2E.
A severe thunderstorm produced a wind gust to 60 mph at Brady.
A severe thunderstorm produced a 60 mph wind gust at Fort Benton 10SW. Zero visibility was reported due to blowing dust.
A severe thunderstorm produced a wind gust to 60 mph at Fort Benton.
A severe thunderstorm produced a wind gust to 59 mph at the Havre airport (Havre 4W).
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2007Every state in 2007This day in weather historyWarnings in Montana, August 2007
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: 47315, 47316, 47317, 47318, 47319, 47321, 47322, 47323, 47324, 47325.