Heavy rain and saturated soils contributed to flooding of especially the Flatwillow Creek and the Musselshell River.
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.
Heavy rain and saturated soils contributed to flooding of especially the Flatwillow Creek and the Musselshell River.
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 31, 7:58 PM MST, 4 hours 2 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GLASGOW MT 858 PM MDT TUE MAY 31 2011 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT... SURFACE HIGH MOVING ACROSS E MT...WITH RESULTING PRESSURE GRADIENTS HAVING ALREADY BECOME VERY WEAK OVER MOST OF THE AREA. GRADIENTS INCREASE LATE TONIGHT...FOR E WINDS IN THE MILK VALLEY. DEW POINTS DROPPED TO THE UPPER 30S THIS AFTERNOON WITH MIXING ALOFT...BUT SHOULD RISE QUITE A BIT WITH DE-COUPLING AND THE MOISTER BOUNDARY LAYER. THEREFORE...PATCHY FOG EXPECTED AS LOWS FALL TO THE LOWER 40S SOME PLACES. NO UPDATE TO ONGOING FORECAST SIMONSEN PREVIOUS SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH THURSDAY....UPPER RIDGING WILL RETURN TO NORTHEAST MONTANA THIS EVENING AHEAD OF AN UPPER TROUGH DIGGING OFF THE WEST COAST. THIS WILL ALLOW FOR A BRIEF RETURN TO DRY CONDITIONS TONIGHT INTO WEDNESDAY. WITH CLEARING SKIES AND CONTINUED LOW LEVEL MOISTURE...PUT SOME MENTION OF PATCHY FOG IN FOR THE FAVORED RIVER VALLEYS. TEMPERATURES WILL WARM TO A BIT MORE SEASONABLE READINGS TOMORROW. GUSTY SOUTHEAST WINDS WILL RETURN BY WEDNESDAY AFTERNOON...AND ANOTHER LAKE WIND ADVISORY LOOKS IN STORE. WEDNESDAY NIGHT WILL BRING INCREASING CLOUD COVER AND SHOWER ACTIVITY AS THE PACIFIC TROUGH MOVES ONSHORE DRIVING A SOUTHWEST FLOW ALOFT. GUSTY SOUTHEAST WINDS WILL CONTINUE AS THE ASSOCIATED SURFACE LOW APPROACHES. THURSDAY CONTINUES TO LOOK FAVORABLE FOR STRONG TO SEVERE THUNDERSTORM DEVELOPMENT. LOW LEVEL MOISTURE IS ADVECTED IN AHEAD OF AN APPROACHING COLD FRONT THAT WILL PUSH THROUGH FROM WEST TO EAST. SPEED SHEAR IS PRESENT AND CAPE VALUES ARE NORTH OF 1000 J/KG FOR SOME LOCATIONS. IN ADDITION TO GUSTY WINDS AND HAIL...HEAVY RAINFALL WILL BE POSSIBLE WHICH COULD COMPLICATE ONGOING FLOODING CONCERNS. GILCHRIST .LONG TERM...THURSDAY NIGHT THROUGH TUESDAY... THURSDAY NIGHT THROUGH FRIDAY NIGHT... A TROUGH WILL EXTEND THROUGH THE PACIFIC NORTHWEST AND INTO EASTERN MONTANA. A MESOSCALE LOW PRESSURE SYSTEM WILL BE CREATED NEAR THE SURFACE IN RESPONSE AND MOVE THROUGH THE REGION ALONG WITH A COLD FRONT AND SHOULD GENERATE A FEW SHOWERS AND THUNDERSTORMS ALONG WITH BRIEF COOLING TEMPERATURES. MODEL CONFIDENCE IS HIGH. SATURDAY THROUGH SUNDAY NIGHT... A RIDGE OVER THE PACIFIC NORTHWEST WILL PROGRESS ACROSS EASTERN MONTANA AND SHOULD CREATE A CLEAR TO PARTLY CLOUDY SET OF PERIODS. MODEL CONFIDENCE STARTS HIGH THROUGH SATURDAY NIGHT AND QUICKLY DROPS TO AVERAGE BY SUNDAY TO SUNDAY NIGHT. MONDAY ONWARD... MODEL CONFIDENCE DROPS INTO THE LOW STAGE QUICKLY. MODELS ARE HAVING A HARD TIME DISCERNING THE MOVEMENT AND FUTURE PLACEMENT OF LARGE SCALE TROUGH OFF OF THE COAST OF CALIFORNIA. 00Z RUN OF THE EC DID NOT JIVE WITH THE GFS HOWEVER NEW 12Z RUN IS BEGINNING TO SKEW TOWARDS THE GFS. CONFIDENCE IN MAIN RUN OF THE GFS IS ALSO LOW DUE TO THE LARGE SPREAD OF ITS ENSEMBLE MEMBERS. BEST GUESS IS THE FOR THE TROUGH TO EJECT OVER THE GREAT BASIN AND SLIGHTLY CURVE NORTH WHICH WOULD BEGIN WETTING THE AREA WITH AFTERNOON THUNDERSTORMS THROUGH MONDAY AND TUESDAY FOLLOWED BY A WEAK COLD FRONT MID WEEK. GAH PREVIOUS LONG TERM DISCUSSION... THE GFS AND EC START OUT IN FAIR AGREEMENT FOR THE EXTENDED...HOWEVER AS THE FORECAST PROGRESS THROUGH THE PERIODS THEY HEAD OFF IN TWO DIFFERENT DIRECTIONS. THEY ARE OK UP THROUGH SUNDAY AT 12Z. AT THIS TIME STAMP THEY START TO SPLIT. THE EC KICKS THE WEST COAST DIGGING LOW OUT AND BRINGS IT UP TO CENTRAL MONTANA BY MONDAY AFTERNOON. THE GFS AND GEM BOTH HOLD THE UPPER LOW BACK WITH THE GFS OVER RENO AND THE GEM OVER BAJA CALIFORNIA. THE EC LEAVES A TROUGH BEHIND OVER THE WESTERN STATES WITH THE MAIN UPPER LOW MOVING INTO THE CENTRAL PRAIRIES OF CANADA. AT THE END OF THE FORECAST PERIOD WITH THE BEGINNING OF NEXT WEEK THE GFS DOES KICK THE UPPER LOW TOWARDS MONTANA IN SIMILAR FASHION AS THE EC A FEW DAYS EARLIER...WHERE THE GEM STILL KEEPS THE UPPER LOW CUT OFF OVER THE DESERT SOUTHWEST. FOR THE SOLUTION KEPT THINGS IN PRETTY HIGH CONFIDENCE THROUGH SUNDAY IN THE EXTENDED AND THEN WENT CLIMO AFTER THAT WITH THE LARGE DIFFERENCES...WHICH DID LEAD TO A TEMPERATURE INCREASE LATE...BUT CLIMO HIGHS ARE MOVING INTO THE 70S. IF THE EC IS MORE CORRECT LOOK FOR THE BELOW NORMALS...WITH THE GFS TEMPS WOULD SNEAK ABOVE. SO AFTER SUNDAY A LOW CONFIDENCE IS BEST IN THE FORECAST AT THIS TIME. FRIDAY KEPT POPS HIGH WITH THE PASSING UPPER TROUGH. SATURDAY AND SUNDAY WENT FAIRLY DRY WITH THE BUILDING RIDGE AND THEN SLOWLY TRANSITIONED INTO CLIMO POPS AFTER THAT. PROTON && .AVIATION... VFR CONDITIONS FOR THE MOST PART THROUGH TOMORROW MORNING WITH POSSIBLE MVFR TO IFR CONDITIONS DUE TO PATCH FOG AROUND THE TERMINALS. VISIBILITY COULD BE IMPACTED ALONG WITH CEILING HEIGHT ALTHOUGH THE PATCHY FOG IS NOT A SURE THING. WINDS WILL BE LIGHT AND VARIABLE OVERNIGHT...THEN THEY WILL SWITCH TO THE SOUTHWEST IN THE MORNING AND INCREASING TO 15 TO 25 KNOTS DURING THE AFTERNOON TOMORROW. RSMITH && .HYDROLOGY... FOR THE MILK AND MUSSELSHELL BASINS...EXPECT ONGOING FLOODING DUE TO THE RAINFALL THAT OCCURRED OVER THE RECENT HOLIDAY WEEKEND. FLOOD WARNINGS ARE IN EFFECT. THE YELLOWSTONE RIVER NEAR GLENDIVE IS EXPECTED TO RETURN TO FLOOD STAGE. A FLOOD WARNING IS IN EFFECT THERE AS WELL. THE MISSOURI RIVER BELOW FORT PECK DAM TO THE NORTH DAKOTA STATE LINE WILL SEE A RISE IN THE RIVER WITH WATER RELEASES FROM FORT PECK RESERVOIR. SEE LATEST HYDROLOGIC OUTLOOK FOR FURTHER DETAILS. && .CLIMATE... MAY 2011 IN GLASGOW SO FAR HAS AVERAGED 4 DEGREES BELOW NORMAL. THIS BY ITSELF IS NOT UNUSUAL. HOWEVER...UNUSUALLY CLOUDY AND RAINY WEATHER FOR THE MONTH HAS LED TO UNUSUALLY LOW VARIABILITY IN THE RECORDED TEMPERATURES WITH MOST DAYS SIMPLY BEING COOL. GLASGOW HAS SEEN 70 DEGREES ONLY ONCE SO FAR THIS YEAR...WITH 70 RECORDED ON MAY 16. THE LATEST DATE FOR A FIRST HIGH OF 70 OR MORE WAS MAY 17 IN 1967 (WHEN IT HIT 84). THE LATEST DATES FOR FIRST HIGHS ABOVE THRESHOLDS FROM 69 TO 80 DEGREES ARE GIVEN IN THE FOLLOWING TABLE...BASED ON DATA BACK TO 1893 AND UP TO 2010: >69 MAY 17 1967 >70 MAY 17 1967 >71 MAY 17 1967 >72 MAY 17 1967 >73 MAY 17 1967 >74 JUN 1 1899 >75 JUN 1 1899 >76 JUN 1 1899 >77 JUN 11 1899 >78 JUN 11 1899 >79 JUN 16 1899 >80 JUN 16 1899 2011 THUS HAS THE RECORD LATEST DATE FOR FIRST TEMPERATURE ABOVE 70...71...72...AND 73 DEGREES AS TEMPERATURES ABOVE THESE THRESHOLDS HAVE YET TO BE REACHED AS OF MAY 30...WITH MORE SUCH RECORDS LIKELY FOR THRESHOLDS OF 74 AND UP. MARTIN && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && WEATHER.GOV/GLASGOW
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GLASGOW MT 231 PM MDT TUE MAY 31 2011 MTZ016-017-059>061-011100- CENTRAL AND SOUTHEAST PHILLIPS-CENTRAL AND SOUTHERN VALLEY- NORTHERN PHILLIPS-SOUTHWEST PHILLIPS-NORTHERN VALLEY- 231 PM MDT TUE MAY 31 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...THIS AFTERNOON AND TONIGHT FLOODING IS OCCURRING ONCE AGAIN ON SMALL STREAMS IN VALLEY AND PHILLIPS COUNTIES...ALONG WITH THE MILK RIVER FROM JUST BELOW SACO TO THE CONFLUENCE WITH THE MISSOURI RIVER. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY FLOODING WILL CONTINUE ALONG THE MILK RIVER AND SOME SMALL STREAMS THROUGH THE WEEK. GUSTY SOUTHEAST WINDS WILL RETURN TO THE AREA WEDNESDAY AFTERNOON. A LAKE WIND ADVISORY MAY BE NEEDED FOR FORT PECK LAKE. THURSDAY COULD BRING A ROUND OF STRONG AFTERNOON THUNDERSTORMS TO THE REGION. THESE STORMS COULD PRODUCE STRONG GUSTY WINDS...HAIL AND OR HEAVY RAINFALL AS THEY PASS THROUGH THE AREA. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ021-022-011100- PETROLEUM-GARFIELD- 231 PM MDT TUE MAY 31 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...THIS AFTERNOON AND TONIGHT FLOODING CONTINUES ON SEVERAL SMALL STREAMS IN THE WARNING AREA ALONG WITH THE MUSSELSHELL RIVER. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY FLOODING WILL CONTINUE ALONG THE MUSSELSHELL RIVER AND SOME SMALL STREAMS THROUGH THE WEEK. GUSTY SOUTHEAST WINDS WILL RETURN TO THE AREA WEDNESDAY AFTERNOON. A LAKE WIND ADVISORY MAY BE NEEDED FOR FORT PECK LAKE. THURSDAY COULD BRING A ROUND OF STRONG AFTERNOON THUNDERSTORMS TO THE REGION. THESE STORMS COULD PRODUCE STRONG GUSTY WINDS...HAIL AND OR HEAVY RAINFALL AS THEY PASS THROUGH THE AREA. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ025>027-011100- DAWSON-PRAIRIE-WIBAUX- 231 PM MDT TUE MAY 31 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...THIS AFTERNOON AND TONIGHT THANKS TO RECENT RAINFALL...FLOODING HAS RETURNED TO THE YELLOWSTONE RIVER AT GLENDIVE. A FLOOD WARNING IS IN EFFECT. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY THURSDAY COULD BRING A ROUND OF STRONG AFTERNOON THUNDERSTORMS TO THE REGION. THESE STORMS COULD PRODUCE STRONG GUSTY WINDS...HAIL AND OR HEAVY RAINFALL AS THEY PASS THROUGH THE AREA. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ020-023-024-062-011100- WESTERN ROOSEVELT-MCCONE-RICHLAND-EASTERN ROOSEVELT- 231 PM MDT TUE MAY 31 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...THIS AFTERNOON AND TONIGHT NO HAZARDOUS WEATHER EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY GUSTY SOUTHEAST WINDS WILL RETURN TO THE AREA WEDNESDAY AFTERNOON. A LAKE WIND ADVISORY MAY BE NEEDED FOR FORT PECK LAKE. THURSDAY COULD BRING A ROUND OF STRONG AFTERNOON THUNDERSTORMS TO THE REGION. THESE STORMS COULD PRODUCE STRONG GUSTY WINDS...HAIL AND OR HEAVY RAINFALL AS THEY PASS THROUGH THE AREA. FLOODING IS EXPECTED ON THE MISSOURI RIVER AS THE ARMY CORPS OF ENGINEERS INCREASES RELEASES FROM FORT PECK RESERVOIR. A HYDROLOGIC OUTLOOK HAS BEEN ISSUED FOR THE MISSOURI RIVER FROM DOWNSTREAM OF FORT PECK DAM THROUGH THE NORTH DAKOTA BORDER. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ018-019-011100- DANIELS-SHERIDAN- 231 PM MDT TUE MAY 31 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...THIS AFTERNOON AND TONIGHT NO HAZARDOUS WEATHER EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY THURSDAY COULD BRING A ROUND OF STRONG AFTERNOON THUNDERSTORMS TO THE REGION. THESE STORMS COULD PRODUCE STRONG GUSTY WINDS...HAIL AND OR HEAVY RAINFALL AS THEY PASS THROUGH THE AREA. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
The national radar mosaic for the moment the first event began.
2 flood. Local standard time, as filed.
The Musselshell River remained out of its banks through much of June as heavy rainfalls downstream caused significant flash flooding. Flatwillow Creek was a major tributary to the flooding, with McDonald and Box Elder Creeks contributing lesser amounts.
The Musselshell River remained out of its banks through much of June as heavy rainfalls downstream caused significant flash flooding. Flatwillow Creek was a major tributary to the flooding, with McDonald and Box Elder Creeks contributing lesser amounts.
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, June 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: 322513, 322950.