The severe thunderstorms mainly affected areas from Opheim into western Daniels County.
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 GGW wrote it up.
The severe thunderstorms mainly affected areas from Opheim into western Daniels County.
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 Glasgow, MT wrote its last area forecast discussion before the first event at Jul 31, 12:44 PM MST, 1 hour 16 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GLASGOW MT 144 PM MDT SAT JUL 31 2010 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH MONDAY... THE UPPER RIDGE AXIS HAS SHIFTED TO OUR EAST RESULTING IN UPPER FLOW BACKING TO THE SW. MOISTURE CONTINUES TO BE EJECTED INTO THIS UPPER FLOW FROM TROUGH ALONG THE PACNW COAST. THUNDERSTORMS HAVE ALREADY STARTED TO FIRE OFF OVER THE INTER-MOUNTAIN WEST AND THE ROCKY MOUNTAINS OF IDAHO. THESE STORMS WILL WORK THEIR WAY IN OUR DIRECTION LATER TODAY OR EVENING. WITH A SURFACE TROUGH SLIDING OVER THE LOCAL AREA...SEVERAL DISTURBANCES IN THE UPPER FLOW AND TEMPERATURES EXPECTED TO RISE ABOVE THE TRIGGER TEMPERATURE OF 32*C...THUNDERSTORMS ARE EXPECTED. CONVECTIVE PARAMETERS SUGGEST MODERATE INSTABILITY...WHICH HAS PROMPTED SPC TO PLACE THE ENTIRE REGION WITHIN THE SLIGHT RISK ZONE ON THE CONVECTIVE OUTLOOK FOR TODAY AND THIS EVENING. SO MAINTAINED SEVERE WORDING IN WX GRIDS FOR THIS EVENING. 18Z GGW SOUNDING WAS CONDUCTED...INDICATED ALMOST AND INCH OF PRECIPITABLE WATER...LIFTED INDEX OF -3.7*C AND MODERATE POSITIVE ENERGY. BEFORE FORECAST PACKAGE WENT OUT...SPC ISSUED A SEVERE THUNDERSTORM WATCH FOR WESTERN MONTANA TO INCLUDE OUR WESTERN ZONES. HAIL SIZE UP TO ONE AND A HALF INCH AND THUNDERSTORM WIND GUSTS TO 75 MPH ARE POSSIBLE. ALSO ANTICIPATE AN ADDITIONAL CONVECTIVE WATCH POSSIBLE FOR THE REMAINDER OF OUR ZONES LATER THIS AFTERNOON. SUNDAY...SURFACE TROUGH SLIDES INTO NORTH DAKOTA WHILE THE SHORT- WAVE UPPER LOW SHIFTS EAST INTO THE NORTHERN ROCKIES AND SOUTHERN ALBERTA...SENDING A COLD FRONT INTO THE REGION. THIS BOUNDARY WILL FOCUS SHOWERS AND THUNDERSTORMS TOWARDS THE NORTHERN ZONES. AGAIN MODERATE INSTABILITY COULD TRIGGER MORE SEVERE STORMS IN OUR NORTHEAST AND EASTERN ZONES BY AFTERNOON AND EVENING. THE COLD FRONT WILL DEPRESS THERMAL RIDGING MORE TO THE SOUTH SO TEMPERATURES SHOULD RUN AROUND NORMAL. MONDAY...SLIGHT UPPER RIDGING SHOULD QUIET CONDITIONS AND NORTHWESTERLY FLOW ALOFT SHOULD KEEP TEMPERATURE NEAR NORMAL. HOWEVER SOUTHWESTERLY FLOW ALOFT OVER WESTERN MONTANA COULD GENERATE ADDITIONAL STORMS THERE...SOME OF WHICH COULD DRIFT INTO OUR AREA. SO WILL MAINTAIN SLIGHT CHANCE FOR THE AFTERNOON. SCT .LONG TERM...MONDAY NIGHT THROUGH SATURDAY... PERSISTENT TROUGH OVER THE NW CONUS AFFECTS THE TUESDAY THROUGH SATURDAY PERIODS. THIS GIVES A GENERALLY SOUTHWEST MIDLEVEL FLOW AND CHANCES FOR PPT AND THUNDER EVERYDAY OF THE EXTENDED. LATEST GFS AND EC MODELS HAVE SIGNIFICANT SHORTWAVE ACTIVITY EJECTING FROM THE TROUGH AND IMPACTING THE CWA EVERY COUPLE DAYS WITH POSSIBLE PERIODS OF RELATIVELY INACTIVE WEATHER IN BETWEEN THESE FEATURES ...THOUGH DETAILS HAVE TYPICAL TIMING AND INTENSITY DISAGREEMENTS. THIS ACTIVITY WILL KEEP TEMPERATURES DOWN A BIT WITH HIGHS AROUND 90. SURFACE WINDS CURRENTLY APPEAR TO BE PERSISTENTLY MODERATE IN STRENGTH. MARTIN PREVIOUS LONG TERM DISCUSSION... LITTLE CHANGE IN THE UPPER AIR PATTERN OVER THE NEXT WEEK...WITH QUITE STRONG HUDSON BAY LOW COUNTERED BY SUBTROPICAL HIGH OVER THE SOUTHERN STATES. FURTHER WEST A WEAK LOW/TROF LINGERS OVER THE PACIFIC NORTHWEST...RESULTING IN NEARLY ZONAL FLOW ACROSS THE NORTHERN PLAINS THROUGH NEXT WEEKEND. SUBTLETIES IN THE FLOW WILL HAVE THE MOST INFLUENCE ON THE SENSIBLE WEATHER...BUT MODELS SHIFTING TIMING AND POSITION OF SMALL SCALE FEATURES SO FAIRLY BROAD BRUSH APPROACH SEEMS BEST AT THIS TIME. OVERALL KEPT POPS NEAR CLIMATOLOGICAL NORMS FOR LATE SUMMER AS MONSOONAL MOISTURE NUDGING NORTHWARD AND WEAK ENERGY FLOWING OVER THE MOUNTAINS. DID GO A LITTLE DRIER ON WEDNESDAY AS SOME INDICATION OF SLIGHT RIDGE DEVELOPING OVER WESTERN MONTANA. HEAT BUILDING UNDER THIS RIDGE EXPECTED TO MOVE EASTWARD INTO THE END OF THE WEEK...BUT LATEST RUN OF THE ECMWF PULLING A FAIRLY STRONG AND COOL SHORTWAVE ACROSS THE CANADIAN PRAIRIES LATE IN THE WEEK. THIS INCREASES THE SPREAD OF POTENTIAL TEMPERATURES FOR THE END OF THE FORECAST...SO KEPT READINGS FOR MAXIMUMS JUST A FEW DEGREES ABOVE NORMAL. EBERT && .AVIATION... A FEW THUNDERSHOWERS HAVE EXITED INTO NORTH DAKOTA THIS EVENING...HOWEVER SOME MORE...POSSIBLY SEVERE...ARE POSSIBLE TONIGHT AND TOMORROW MORNING WHICH COULD TEMPORARILY REDUCE CONDITIONS TO MVFR AND PRODUCE STRONG WIND GUSTS AND HAIL. PREVAILING CONDITIONS OUTSIDE OF STORMS ARE VFR WITH WINDS AROUND 10KTS THROUGH SUNDAY...AND AREAS OF HIGH AND MID LEVEL CLOUDS. MARTIN && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && WEATHER.GOV/GLASGOW
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GLASGOW MT 225 PM MDT SAT JUL 31 2010 MTZ016>027-059>062-011100- CENTRAL AND SOUTHEAST PHILLIPS-CENTRAL AND SOUTHERN VALLEY- DANIELS-SHERIDAN-WESTERN ROOSEVELT-PETROLEUM-GARFIELD-MCCONE- RICHLAND-DAWSON-PRAIRIE-WIBAUX-NORTHERN PHILLIPS- SOUTHWEST PHILLIPS-NORTHERN VALLEY-EASTERN ROOSEVELT- 225 PM MDT SAT JUL 31 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...TODAY AND TONIGHT SCATTERED STRONG TO SEVERE THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON AND EVENING ACROSS NORTHEAST MONTANA WITH THE MAIN THREATS BEING POSSIBLE FREQUENT CLOUD TO GROUND LIGHTNING...LARGE HAIL...DAMAGING WINDS...AND HEAVY RAINFALL. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY THUNDERSTORMS WILL BE POSSIBLE AGAIN SUNDAY AFTERNOON AND EVENING. SOME OF THE STRONGER STORMS MAY BECOME SEVERE ALONG AND EAST OF A LINE FROM MALTA TO WIBAUX WITH MAIN THREATS BEING LARGE HAIL AND DAMAGING WINDS. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE GLASGOW MT 250 PM MDT SAT JUL 31 2010 MTZ018-061-312145- DANIELS-VALLEY- 250 PM MDT SAT JUL 31 2010 THE NATIONAL WEATHER SERVICE IN GLASGOW HAS ISSUED A SIGNIFICANT WEATHER ADVISORY FOR... NORTHEASTERN VALLEY COUNTY IN NORTHEAST MONTANA... NORTHWESTERN DANIELS COUNTY IN NORTHEAST MONTANA... UNTIL 345 PM MDT. AT 248 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM 8 MILES NORTH OF RICHLAND..MOVING EAST AT 25 MPH. HAIL UP TO ONE-HALF INCH IN DIAMETER AND WIND GUSTS UP TO 50 MPH ARE EXPECTED WITH THIS STORM. LOCATIONS IN THE ADVISORY INCLUDE... RURAL AREAS OF NORTHWESTERN DANIELS COUNTY... RURAL AREAS OF NORTHERN DANIELS COUNTY... LAT...LON 4888 10533 4888 10613 4900 10634 4901 10537 TIME...MOT...LOC 2050Z 260DEG 21KT 4893 10608 WJM WEATHER.GOV/GLASGOW
The Glasgow radar (KGGW), 108 km away, was scanning. The volume nearest the first event began at 21:01 UTC.
4 thunderstorm wind, 2 hail. Local standard time, as filed.
Observer witnessed estimated 60 mph gusts for 10 minutes.
Hail combined with strong winds destroyed 600 acres of wheat.
Wind combined with hail destroyed wheat crop.
Light rain is also falling.
Two power poles were knocked down and visibility reduced to near zero by the strong winds. Hail was beginning to fall.
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, July 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: 244993, 244997, 245044, 245057, 245056, 245055.