A disturbance ejecting northeast across the area produced severe thunderstorms beginning across near Fort Peck lake that tracked east across McCone county and stretched north-south as it approached the North Dakota border. A weak tornado possibly touched down.
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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.
A disturbance ejecting northeast across the area produced severe thunderstorms beginning across near Fort Peck lake that tracked east across McCone county and stretched north-south as it approached the North Dakota border. A weak tornado possibly touched down.
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 Jun 21, 1:47 PM MST, 1 hour 13 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GLASGOW MT 247 PM MDT MON JUN 21 2010 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH WEDNESDAY... STRONG UPPER LOW MOVING THROUGH WESTERN MONTANA THIS AFTERNOON. THUNDERSTORMS ALREADY GOING OVER CENTRAL MONTANA AHEAD OF THE WAVE. AS THE WAVE MOVES FURTHER EAST EXPECT THUNDERSTORMS TO SPREAD INTO CWA FOR THE LATE AFTERNOON AND EVENING. LIFTED INDEX AT MINUS 7C WITH CAPE OF 1500 J/KG IN PLACE ACROSS EASTERN MONTANA NOT QUITE AS UNSTABLE AS PREVIOUSLY EXPECTED BUT STILL ENOUGH FOR SOME SEVERE THUNDERSTORMS WITH THE COLD FRONTAL PASSAGE TODAY. EVEN WITHOUT SEVERE CONVECTION...HEAVY RAIN IS STILL EXPECTED SO WILL CONTINUE THE FLASH FLOOD WATCH. LOW LIFTS INTO SASKATCHEWAN LATER TONIGHT BUT DISORGANIZED UPPER TROF LINGERS OVER THE REGION THROUGH TUESDAY WITH ENOUGH VORTICITY TO PRODUCE SHOWERS IN THE MOIST AIRMASS. DRY WEATHER RETURNS WEDNESDAY AS AN UPPER LEVEL RIDGE BUILDS OVER MONTANA. EBERT .LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY... DID NOT MAKE TOO MANY CHANGES TO THE LONG TERM FORECAST AS IT STARTS WITH AN UPPER LEVEL RIDGE OVER EASTERN MONTANA AND AN APPROACHING SHORTWAVE FROM THE PACIFIC NORTHWEST. THE SHORTWAVE WILL CREATE SOUTHWEST FLOW ALOFT ACROSS EASTERN MONTANA AND INSTABILITY FOR THURSDAY AFTERNOON AND THURSDAY NIGHT. A FEW DISTURBANCES WILL MOVE ALONG THE FLOW THURSDAY AFTERNOON AND THURSDAY EVENING GENERATING THUNDERSTORMS. FRIDAY A THERMAL RIDGE WILL INCREASE HIGHS ACROSS EASTERN MONTANA INTO THE UPPER 80S SO DID INCREASE THE HIGHS ON FRIDAY AHEAD OF THE COLD FRONT WHICH WILL MOVE THROUGH EASTERN MONTANA FRIDAY EVENING. SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AHEAD OF THIS COLD FRONT AND JUST BEHIND THE FRONT. THE THUNDERSTORMS BEHIND THE FRONT WILL BE MORE ISOLATED AND EMBEDDED IN STRATIFORM RAIN. AT THIS POINT THE 12Z RUN AND THE 00Z RUN OF THE GFS TEND TO DISAGREE ABOUT WHAT WILL HAPPEN ON SATURDAY. OOZ GFS KEEPS EASTERN MONTANA UNDER A GENERAL AREA OF TROFFINESS WITH CHANCES OF PRECIPITATION ACROSS EASTERN MONTANA. THE 12Z GFS RUN HAS THE UPPER TROF FURTHER TO THE NORTH SO MONTANA WILL BE UNDER ZONAL FLOW. IT ALSO BRING DRIER AIR INTO EASTERN MONTANA AND PUSHING THE QPF INTO NORTH DAKOTA. THE OOZ ECMWF KEEPS EASTERN MONTANA UNDER THE AREA OF TROFFINESS AND QPF OVER THROUGH SATURDAY EVENING LIKE THE 00Z GFS. THE 12Z GEM AGREES WITH THE DRIER ZONAL FLOW OF THE 12Z GFS FOR SATURDAY. WITH THIS MUCH DISAGREEMENT IN THE MODELS DID NOT MAKE ANY CHANGES PAST SATURDAY. THE BROAD BRUSHED POPS FOR THE WEEKEND ARE FINE FOR NOW. THE MODELS DID AGREE ON ZONAL FLOW FOR SUNDAY NIGHT SO DID DROP THE POPS BELOW 15% DURING THIS TIME FRAME. RSMITH PREVIOUS DISCUSSION...THE UPPER RIDGE MOVES TO THE EAST ON THURSDAY WITH THE FLOW ALOFT TURNING TO THE SOUTHWEST. DECENT SHORTWAVE/FRONTAL SYSTEM MOVES THROUGH THE AREA THURSDAY NIGHT. FOR FRIDAY AND SATURDAY...MODELS HAVE VARIED FROM BEING ZONAL TO HAVING SOUTHWEST FLOW ALOFT. AT THIS POINT...BOTH THE GFS AND ECMWF HAVE SOUTHWEST FLOW ALOFT. EITHER WAY...EXPECT FREQUENT SHORTWAVES WITH VARYING STRENGTHS. ANYONE OF THEM COULD PRODUCE THUNDERSTORMS. A SHORTWAVE RIDGE PASSES ON SATURDAY NIGHT INTO SUNDAY WITH A RETURN TO SOUTHWEST FLOW ALOFT BY SUNDAY NIGHT AND MORE SHORTWAVES. WITH THE WET PATTERN OF LATE...NOT READY TO GO DRY FOR ANY 12 HOUR PERIOD. WILL BROAD BRUSH FORECAST WITH A SLIGHT CHANCE OF THUNDERSTORMS FOR NOW. FORRESTER && .AVIATION... EXPECT CUMULUS CLOUDS TO DEVELOP BY AFTERNOON AND THE THUNDERSTORMS WILL DEVELOP BY LATE AFTERNOON AND MOVE EAST ACROSS THE AREA THROUGH THIS EVENING. HEAVY RAIN...HAIL AND STRONG ERRATIC THUNDERSTORMS WIND GUSTS WILL BE POSSIBLE WITH THESE STORMS...SO EXPECT PERIODS OF MVFR TO IFR CONDITIONS. THESE STORMS WILL MOVE TO THE EAST AFTER MIDNIGHT...LEAVING BEHIND SCATTERED TO BROKEN LAYER OF MAINLY MID LEVEL CLOUDS THE REST OF THE NIGHT. RSMITH && .HYDROLOGY... MANY SMALL STREAMS AND CREEKS ACROSS THE AREA CONTINUE TO RUN HIGH BUT ARE GENERALLY CONTAINED WITHIN THEIR BANKS. ANOTHER UPPER WAVE APPROACHING THE REGION WILL GENERATE WIDESPREAD THUNDERSTORMS THIS AFTERNOON THROUGH EVENING. SOME OF THE THUNDERSTORMS MAY CONTAIN HEAVY RAIN WHICH WOULD PUSH AFFECTED STREAMS BACK OUT OF THEIR BANKS. A FLASH FLOOD WATCH IS IN EFFECT FOR ALL OF NORTHEAST MONTANA FOR TODAY AND TONIGHT. && .GLASGOW WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR CENTRAL AND SOUTHEAST PHILLIPS...CENTRAL AND SOUTHERN VALLEY...DANIELS...SHERIDAN... WESTERN ROOSEVELT...NORTHERN PHILLIPS...SOUTHWEST PHILLIPS... NORTHERN VALLEY...EASTERN ROOSEVELT. FLASH FLOOD WATCH THROUGH LATE TONIGHT FOR PETROLEUM... GARFIELD...MCCONE...RICHLAND...DAWSON...PRAIRIE...WIBAUX. && WEATHER.GOV/GLASGOW
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GLASGOW MT 332 AM MDT MON JUN 21 2010 MTZ021>027-220900- PETROLEUM-GARFIELD-MCCONE-RICHLAND-DAWSON-PRAIRIE-WIBAUX- 332 AM MDT MON JUN 21 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...TODAY AND TONIGHT A STRONG COLD FRONT WILL MOVE INTO NORTHEAST MONTANA TODAY WHICH WILL LIKELY PRODUCE SEVERE THUNDERSTORMS IN THE AFTERNOON AND EVENING. HEAVY RAIN...STRONG WINDS AND LARGE HAIL ARE POSSIBLE. THE FLASH FLOOD WATCH REMAINS IN EFFECT AND WILL CONTINUE FOR THE AREA THROUGH TONIGHT. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY NO HAZARDOUS WEATHER IS EXPECTED. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ016>020-059>062-220900- CENTRAL AND SOUTHEAST PHILLIPS-CENTRAL AND SOUTHERN VALLEY- DANIELS-SHERIDAN-WESTERN ROOSEVELT-NORTHERN PHILLIPS- SOUTHWEST PHILLIPS-NORTHERN VALLEY-EASTERN ROOSEVELT- 332 AM MDT MON JUN 21 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...TODAY AND TONIGHT A STRONG COLD FRONT WILL MOVE INTO NORTHEAST MONTANA TODAY WHICH WILL LIKELY PRODUCE SEVERE THUNDERSTORMS IN THE AFTERNOON AND EVENING. HEAVY RAIN...STRONG WINDS AND LARGE HAIL ARE POSSIBLE. SINCE CREEKS AND STREAMS ARE ALREADY RUNNING NEAR CAPACITY A FLASH FLOOD WATCH WAS ISSUED BEGINNING TODAY AT NOON AND LASTING THROUGH TONIGHT. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY NO HAZARDOUS WEATHER IS EXPECTED. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
The Glasgow radar (KGGW), 58 km away, was scanning. The volume nearest the first event began at 22:00 UTC.
11 hail, 3 thunderstorm wind, 2 funnel cloud, 1 tornado, 1 heavy rain. Local standard time, as filed.
Coop Observer reported a brief touchdown in very rural area of SW Valley County.
Golfball size hail was falling at the Hell Creek Recreation Area.
Spotter witnessed two funnel clouds a half mile apart.
Nickel to quarter size hail fell in the area resulting in the destruction of some alfalfa crop.
At 1615 MST 18 miles southeast of Fort Peck, law enforcement officer reported 2.75 inch hail while one inch hail covered the ground on Highway 24. Up to one inch hail was reported by an NWS employee 10 miles southeast of Fort Peck Handar.
Reported on Highway 24.
Clouds were rotating with 50 mph winds accompanying the hail. A window was broken from the storm.
Five miles southwest of Vida, the crops were laying flat with almost 100% loss.
Small tree branches were observed falling out of the tree. Rotation in the clouds were also reported.
Storm brought 1.75 hail and strong winds caught damage to rain gutters, air conditioner units and window seals.
Large hail also occurred with this wind, causing damage to rain gutters, air conditioning units and window seals.
Spotter observed water running off of the yard with large puddles visible in the wheat field.
Heavy rain mixed with the hail. Also a rapid drop in temperature occurred with 40 to 50 mph winds.
Spotter reported one inch hail.
Spotter reported large trees bending in the strong winds.
Strong winds blew flagpole and lawn furniture away.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2010Every state in 2010This day in weather historyThe tornado archive for Montana, 2010Warnings in Montana, June 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: 238267, 238268, 238273, 238277, 238284, 255362, 238319, 242931, 255366, 238322, 255441, 255443, 255442, 238327, 255444, 238329, 238332, 238334.