A few severe thunderstorms produced large hail and heavy rainfall. The areas affected were in southern Valley County, Richland, Dawson and Priairie counties.
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.
A few severe thunderstorms produced large hail and heavy rainfall. The areas affected were in southern Valley County, Richland, Dawson and Priairie counties.
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 May 28, 8:12 PM MST, 1 hour 28 minutes earlier.
AREA FORECAST DISCUSSION...CORRECTED NATIONAL WEATHER SERVICE GLASGOW MT 912 PM MDT FRI MAY 28 2010 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT... LARGE CLOSD UPPER LOW CENTER OVER E OR MOVING SLOWLY E. DEEPENING COOL AIRMASS IN LOWER LEVELS IN NE FLOW...AND VERY MOIST AS WELL. SATELLITE CHANNELS SHOWED OVERCAST THROUGHOUT CWA CONTINUING INTO EVENING. MEANWHILE...STRONG SSW FLOW ALOFT WITH UP TO 100 KT JET ON 00Z KGGW SOUNDING. INCREASING MOISTURE...WITH QPF UP TO 1.3 TONIGHT...AND LARGE-SCALE DYNAMIC LIFT WILL BE IMPRESSIVE TONIGHT...WITH WIDESPREAD RAINFALL SPREADING CURRENTLY INTO OUR W...REACHING OUR E AFTER MIDNIGHT. CONVECTION INCREASING WITH DEVELOPING SURFACE WAVE IN WY THAT WILL MOVE NE INTO SE MT AND OUR EXTREME SE. DIFFICULT TO GET SEVERE CONVECTION WITH DEEPENING LOW-LEVEL COOL AIRMASS...BUT STRONG DYNAMICS AND DEEP MOISTURE IN THIS PATTERN WITH INSTABILITY ALOFT WILL PROBABLY BE ENOUGH TO GENERATE A QUITE A BIT OF STRONG THUNDERSTORMS TONIGHT...A FEW POSSIBLY SEVERE IN OUR E WITH HAIL PER LATEST SWODY1. MAIN UPDATE TO ADJUST WEATHER AND POPS...LOWER LOWS. SIMONSEN PREVIOUS SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH SUNDAY...ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ARE EXPECTED TO AFFECT THE AREA TONIGHT. THIS SHOULD BE MORE WIDESPREAD IN REGARDS TO PRECIPITATION COVERAGE THAN THE PAST COUPLE OF NIGHTS. SEVERE COVERAGE SHOULD BE CONFINED TO THE SOUTHEAST ZONES. FLASH FLOODING POTENTIAL AGAIN LOOKS GOOD AGAIN WITH THE SAME AREA AS THE PAST COUPLE OF NIGHTS AND THIS IS HIGHLIGHTED WITH THE CURRENT FLASH FLOOD WATCH (OVER ALL OF THE CWA BUT PHILLIPS/GARFIELD AND PETROLEUM COUNTIES). UPPER LOW OVER THE WESTERN STATES IS EXPECTED TO LIFT NORTHEAST AND INTO THE PRAIRIE PROVINCES LATE SATURDAY. ENERGY ON THE LEADING EDGE WILL BRING THE LAST DECENT SHOWER/THUNDERSTORM POTENTIAL TO THE AREA TONIGHT. PRECIP MOVES OUT BY SATURDAY MORNING WITH A DRY SLOT MOVING IN FROM THE SOUTHWEST. UNSTABLE AIRMASS MOVES WELL TO OUR EAST TAKING THE SHOWERS/THUNDERSTORM THREAT INTO THE DAKOTAS. SATURDAY NIGHT AND SUNDAY...PRECIPITATION LOOKS TO REMAIN MAINLY OVER THE PRAIRIE PROVINCES WHERE A VERY COLD POOL ALOFT WILL BE GENERATING ACCUMULATING SNOW NORTH OF THE INTERNATIONAL BORDER. A DRIER AND WARMER (OR LESS COLDER AIR) AIRMASS WILL BE CONFINED TO NORTHEAST MONTANA BUT SOME LIGHT SHOWERY PRECIPITATION IS A POSSIBILITY. IT COULD MIX WITH A SNOWFLAKE OR TWO IN SPOTS IN THE NORTH AND WEST BUT NO ACCUMULATION IS EXPECTED. JAMBA .LONG TERM...SUNDAY NIGHT THROUGH FRIDAY... ADJUSTED THE LONG TERM GRIDS MOSTLY FOR COLLABORATION AND TO BLEND WITH NEWEST MODEL GUIDANCE. ALTHOUGH SOME DISAGREEMENT BETWEEN THE EXTENDED MODELS LESSENED THE CONFIDENCE OF PORTIONS OF THE EXTENDED FORECAST...ESPECIALLY WITH POPS AND THE DEPICTION AND TIMING OF QPF. MODEL RUN TO RUN CONSISTENCY IS LACKING IN THE 500 MB HEIGHT FIELD. BASICALLY COMPROMISED USING A BLEND OF THE EXTENDED MODELS. OTHERWISE...GOING EXTENDED FORECAST LOOKS GOOD. BMICKELSON THE UPPER LOW MOVES INTO CENTRAL SASKATCHEWAN AND THE UPPER TROF FLATTEN OUT AS UPPER FLOW BECOME ZONAL ON SUNDAY NIGHT. THE ZONAL FLOW AND WEAK RIDGING ALOFT IS EXPECTED FOR MONDAY AND MOST OF TUESDAY. THIS WILL BRING SLIGHTLY WARMER AND DRIER WEATHER FOR MONDAY THROUGH TUESDAY MORNING. ANOTHER SHORTWAVE WILL MOVE INTO WESTERN MONTANA ON TUESDAY AND MOVE ACROSS EASTERN MONTANA TUESDAY EVENING INTO WEDNESDAY AFTERNOON IN A NEGATIVE TILTED FASHION. SOUTHWEST FLOW AHEAD OF THIS TROUGH WILL BRING SOME MOISTURE INTO EASTERN MONTANA BY TUESDAY AFTERNOON. THIS ALONG WITH THE FORCING WILL BE ENOUGH TO PRODUCE A CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS EASTERN MONTANA THROUGH WEDNESDAY AFTERNOON. AS THE NEGATIVELY TILTED TROF PUSHES INTO NORTH DAKOTA AND SHORTWAVE RIDGING MOVES INTO EASTERN MONTANA. ACCORDING THE THE LATEST ECMWF RUN THE WEAK RIDGES MOVE THROUGH FAST AND BY THURSDAY AFTERNOON THE FLOW OVER EASTERN MONTANA BECOMES SLIGHTLY SOUTHWEST...WHICH MEANS A SLIGHT CHANCE OF CONVECTION THURSDAY AFTERNOON AND EVENING. ACCORDING TO THE LATEST GFS THE UPPER LEVEL RIDGE IS STRONGER AND THE REGION WILL REMAIN DRY THURSDAY AFTERNOON AND INTO SATURDAY MORNING. WITH THESE DIFFERENCES IN THE MODELS DECIDED NOT TO CHANGE THE FORECAST PAST THURSDAY AFTERNOON. EVEN THOUGH THE GFS IS DRIER WENT ALONG WITH THE ECMWF AND LEFT A CHANCE OF THUNDERSTORMS IN THE FORECAST ON THURSDAY AFTERNOON AND EVENING...GIVEN THAT IT IS EARLY JUNE AND WE ARE INTO CONVECTIVE SEASON. RSMITH && .AVIATION... MVFR CONDITIONS AT THE KGGW AND KOLF TERMINALS WHILE IFR CONDITIONS EXIST AT THE KGDV AND KSDY TERMINALS OVERNIGHT AND INTO SATURDAY MORNING. SHOWERS AND THUNDERSTORMS CAN BE EXPECTED ACROSS THE KDSY AND KGDV TERMINALS TONIGHT. SOME THESE STORM WILL BECOME SEVERE WITH LARGE HAIL AND DAMAGING WINDS THE PRIMARY THREAT. WINDS WILL GENERALLY BE OUT OF THE NORTH AND NORTHWEST AT 10 TO 20 KNOTS...BUT MORE ERRATIC AND GUSTIER WINDS CAN BE EXPECTED NEAR THE STRONGER STORMS. RSMITH && .GLASGOW WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH UNTIL 6 AM MDT SATURDAY FOR CENTRAL AND SOUTHERN VALLEY...DANIELS...SHERIDAN...WESTERN ROOSEVELT... MCCONE...RICHLAND...DAWSON...PRAIRIE...WIBAUX...NORTHERN VALLEY...EASTERN ROOSEVELT. && WEATHER.GOV/GLASGOW
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GLASGOW MT 1024 AM MDT FRI MAY 28 2010 MTZ017>020-023>027-061-062-291200- CENTRAL AND SOUTHERN VALLEY-DANIELS-SHERIDAN-WESTERN ROOSEVELT- MCCONE-RICHLAND-DAWSON-PRAIRIE-WIBAUX-NORTHERN VALLEY- EASTERN ROOSEVELT- 1024 AM MDT FRI MAY 28 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...TODAY AND TONIGHT A FLASH FLOOD WATCH IS IN EFFECT TONIGHT. THUNDERSTORMS WITH HEAVY RAIN IS POSSIBLE AGAIN TONIGHT. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY COLD AIR WILL IMPACT NORTHEAST MONTANA FOR THE MEMORIAL DAY WEEKEND. MORE RAIN IS LIKELY SATURDAY AND SATURDAY NIGHT. TEMPERATURES WILL BE COLD ENOUGH SATURDAY NIGHT AND SUNDAY MORNING THAT A MIX OF RAIN AND SNOW IS POSSIBLE NORTH OF THE MISSOURI RIVER. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ016-021-022-059-060-291200- CENTRAL AND SOUTHEAST PHILLIPS-PETROLEUM-GARFIELD- NORTHERN PHILLIPS-SOUTHWEST PHILLIPS- 1024 AM MDT FRI MAY 28 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...TODAY AND TONIGHT NO HAZARDOUS WEATHER EXPECTED TODAY AND TONIGHT. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY COLD AIR WILL IMPACT NORTHEAST MONTANA FOR THE MEMORIAL DAY WEEKEND. MORE RAIN IS LIKELY SATURDAY AND SATURDAY NIGHT. TEMPERATURES WILL BE COLD ENOUGH SATURDAY NIGHT AND SUNDAY MORNING THAT A MIX OF RAIN AND SNOW IS POSSIBLE NORTH OF THE MISSOURI RIVER AND OVER THE LITTLE ROCKY MOUNTAINS. .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
1014 PM MDT FRI MAY 28 2010
MTZ017-022-023-290515-
MCCONE-GARFIELD-VALLEY-
1014 PM MDT FRI MAY 28 2010
THE NATIONAL WEATHER SERVICE IN GLASGOW HAS ISSUED A
SIGNIFICANT WEATHER ADVISORY FOR...
SOUTHERN VALLEY COUNTY IN NORTHEAST MONTANA...
EASTERN GARFIELD COUNTY IN NORTHEAST MONTANA...
WESTERN MCCONE COUNTY IN NORTHEAST MONTANA...
UNTIL 1115 PM MDT.
AT 1010 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
STRONG THUNDERSTORMS BETWEEN 11 MILES SOUTH OF THE PINES REC AREA TO
JORDAN TO THE NELSON CREEK REC AREA...AND MOVING NORTH AT 50 MPH.
HAIL UP TO THE SIZE OF PENNIES IS EXPECTED WITH THESE STORMS...ALONG
WITH HEAVY RAIN.
LOCATIONS IN THE ADVISORY INCLUDE...
THE PINES REC AREA AND FLOWING WELLS REST AREA...
DUCK CREEK REC AREA...
FORT PECK AND NELSON CREEK REC AREA...
GLASGOW...
ROCK CREEK REC AREA...
NASHUA...
FRAZER...
THIS STORM MAY INTENSIFY...AND A SEVERE THUNDERSTORM WATCH IS IN
EFFECT FOR THIS AREA. BE CERTAIN TO MONITOR LOCAL RADIO AND TV
STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS...FOR ADDITIONAL
INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.
LAT...LON 4837 10682 4837 10587 4718 10606 4718 10609
4688 10615 4686 10716
TIME...MOT...LOC 0413Z 197DEG 56KT 4772 10659 4733 10668
GFF
WEATHER.GOV/GLASGOWThe Glasgow radar (KGGW), 6 km away, was scanning. The volume nearest the first event began at 04:38 UTC.
3 hail, 3 heavy rain, 1 flash flood. Local standard time, as filed.
A severe thunderstorm tracked north through Glasgow dropping up to 1.75 inch hail. Basement window broken at a house in Glasgow.
Mostly 0.75 inch hail with some stones one inch and slightly larger.
A law enforcement officer reported one inch hail.
Flash flooding washed out low spot on County Road 120.
Richland County Law enforcement reported a washed out low spot on County Highway 120 about two miles west of Highway 16.
Heavy rain closed the Berry Street underpass with six feet of water. Highway 16 near milemarker 8 also experienced water over the road.
Rainfall of 1.07 inches fell from a thunderstorm.
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, May 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: 223166, 223161, 223163, 223160, 238590, 238591, 223162.