Heavy rain fell on saturated ground resulting in flooding across the area.
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 fell on saturated ground resulting in flooding across the area.
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 30, 1:13 PM MST, 6 hours 35 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GLASGOW MT ISSUED BY NATIONAL WEATHER SERVICE BILLINGS MT 213 PM MDT MON MAY 30 2011 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH WEDNESDAY... NO CHANGES TO HIGHLIGHTS CURRENTLY IN EFFECT...WHICH INCLUDE A FLOOD WATCH FOR MOST OF THE AREA...VARIOUS FLOOD WARNINGS...A FORT PECK LAKE WIND ADVISORY...AND A HIGH WIND WATCH FOR OUR EAST HALF WHICH BEGINS AT 06Z TONIGHT. UPPER LOW LIFTING INTO SOUTHEAST MONTANA CONTINUES TO SPREAD WIDESPREAD RAIN TO MUCH OF THE AREA...WITH DRY SLOTTING AT MID LEVELS ALLOWING FOR MORE CONVECTIVE AND A BIT LESS WIDESPREAD SHOWERS IN OUR FAR SOUTHEAST THIS AFTERNOON. LOCAL OBS SHOW A HALF INCH TO INCH OF RAIN HAS FALLEN OVER MOST OF THE AREA OVER THE PAST 24 HOURS. ANOTHER HALF INCH TO INCH IS POSSIBLE THROUGH TONIGHT AND TUESDAY MORNING. UPPER LOW WILL LIFT NORTHEAST AND OUT OF THE AREA BY TOMORROW AFTERNOON. SFC LOW NEAR THE MT/WY/SD BORDERS WILL DEEPEN AS IT LIFTS INTO ND TONIGHT. TIGHTENING GRADIENT SUPPORTS INCREASED NW WINDS IN OUR AREA LATE TONIGHT INTO TUESDAY. LATEST MODELS HAVE TRENDED A BIT WEAKER WITH THE WINDS...WITH THE MAV SIGNIFICANTLY STRONGER THAN THE NAM. A COUPLE THINGS ARE AGAINST HIGH WIND...ONE BEING LINGERING LIFT ASSOCIATED WITH THE UPPER LOW...THE OTHER THE FACT THAT THE ISALLOBARIC WIND WILL BE AGAINST THE SFC FLOW WITH A PRESSURE RISE MAX IN SD TOMORROW MORNING. THAT BEING SAID THERE WILL BE 35-45 KTS OF WIND AT 850MB TO TAP INTO. HAVE TAPERED WIND GUSTS DOWN A BIT BUT WILL KEEP HIGH WIND WATCH GOING AND LET EVENING SHIFT TAKE A FINAL LOOK. THINGS WILL QUIET DOWN TUESDAY AFTERNOON WITH RIDGING IN THE WAKE OF THE DEPARTING LOW. DRY/WARMER WEATHER IN STORE THROUGH WEDNESDAY WITH HIGH TEMPS INTO THE LOWER 70S BY MIDWEEK. GOOD SURGE OF LOW LEVEL MOISTURE ADVECTING UP THE HIGH PLAINS SHOULD SET THE STAGE FOR INCREASED CONVECTIVE CHANCES BY PERHAPS LATE WEDNESDAY NIGHT PER LOW LEVEL JET FORCING. JKL .LONG TERM...THURSDAY THROUGH MONDAY... COMBINATION OF COUPLE OF SHORTWAVES EMBEDDED IN SW FLOW ALOFT AND MUCH INCREASED LOW LEVEL MOISTURE WILL INCREASE THE THREAT OF SHOWERS AND THUNDERSTORMS THURSDAY. SHEAR AND INSTABILITY SUGGEST SOME STRONG STORMS ARE EVEN POSSIBLE. MODELS IN PRETTY GOOD AGREEMENT IN SHOWING A SOLID CHANCE OF POST FRONTAL PCPN ON FRIDAY WITH ADDITIONAL ENERGY AND HINT OF A WEAK TROWAL IN NW FLOW. HAVE RAISED POPS A BIT ESPECIALLY IN WESTERN PARTS TO COVER THIS. MODELS HAVE BEEN INCONSISTENT THEREAFTER...BOTH IN TERMS OF POTENTIAL SHORTWAVE ENERGY FROM THE NORTHWEST AND FATE OF DEEP PACIFIC ENERGY AS IT SETTLES ALONG THE OR/CA COAST. LATEST ECMWF/GFS RUNS KEEP BOTH OUT OF NORTHEAST MONTANA AND ALLOW FOR RIDGING/HIGHER HEIGHTS AND WARMER/DRIER CONDITIONS THROUGH THE WEEKEND. UKMET IS A BIT MORE PROGRESSIVE WITH THE PACIFIC TROF AS IT KICKS IT TOWARD THE GREAT BASIN AND CENTRAL ROCKIES BY SUNDAY. CANADIAN WAVE MAY OFFER A WEAK BACKDOOR FRONT OVER THE WEEKEND AND THIS WILL NEED TO BE MONITORED AS WELL. WITH THIS UNCERTAINTY IN MIND WILL KEEP SATURDAY DRY WITH NEAR CLIMO/SLIGHT POPS INTRODUCED FOR SUNDAY AND MONDAY. AS FOR TEMPS...WARM DAY THURSDAY WITH WILL BE FOLLOWED BY A POST FRONTAL SEASONABLY COOL DAY FRIDAY. WARMING TREND SHOULD BE IN STORE FOR THE WEEKEND WITH TEMPS HEADING BACK TO ABOVE NORMAL BY SUNDAY...AND PERHAPS MONDAY IF THE BREAKDOWN OF THE RIDGE HOLDS OFF. JKL && .AVIATION... UPPER LOW IN SOUTHEAST MT WILL LIFT THROUGH NORTHEAST MT TONIGHT THEN EXIT THE REGION TOMORROW. EXPECT WIDESPREAD SHOWERS TO CONTINUE THROUGH MOST OF THE NIGHT...THEN TAPER OFF FROM SW TO NE LATE TONIGHT AND TUESDAY...ENDING BY EARLY AFTERNOON. MVFR TO IFR WITH LOCAL LIFR CAN BE EXPECTED AT ALL TAF SITES...WITH LOCAL LIFR POSSIBLE IN THE HEAVIER SHOWERS. LOOK FOR AN IMPROVEMENT TO VFR ACROSS THE FORECAST AREA ON TUESDAY. EAST TO NORTHEAST WIND GUSTS OF 20-30 KTS THIS AFTERNOON WILL SHIFT TO THE NW AND INCREASE LATE TONIGHT AND EARLY TUESDAY. GUSTS OF 35-45 KTS ARE POSSIBLE FROM KGGW-KOLF-KSDY-KGDV BETWEEN 09-18Z...WITH STRONGEST WINDS ALONG THE NORTH DAKOTA BORDER. WINDS WILL BEGIN TO DECREASE TUESDAY AFTERNOON. JKL && .GLASGOW WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH THROUGH LATE TUESDAY NIGHT FOR CENTRAL AND SOUTHEAST PHILLIPS...CENTRAL AND SOUTHERN VALLEY...DANIELS...SHERIDAN... WESTERN ROOSEVELT...PETROLEUM...GARFIELD...MCCONE...NORTHERN PHILLIPS...SOUTHWEST PHILLIPS...NORTHERN VALLEY...EASTERN ROOSEVELT. LAKE WIND ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR FORT PECK LAKE. HIGH WIND WATCH FROM MIDNIGHT MDT TONIGHT THROUGH TUESDAY AFTERNOON 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 ISSUED BY NATIONAL WEATHER SERVICE BILLINGS MT 222 PM MDT MON MAY 30 2011 MTZ016>027-059>062-312030- 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- 222 PM MDT MON MAY 30 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...THIS AFTERNOON AND TONIGHT A SLOW MOVING STORM SYSTEM WILL CONTINUE TO BRING WIDESPREAD RAIN TO THE AREA THROUGH TONIGHT. VARIOUS FLOOD WATCHES AND WARNINGS ARE IN EFFECT. NORTHEAST WINDS GUSTING TO 40 MPH CAN BE EXPECTED OVER FORT PECK LAKE THROUGH THIS EVENING. RECREATIONISTS SHOULD USE CAUTION. STRONG NORTHWEST WINDS WILL DEVELOP LATE TONIGHT. GUSTS OF 50 TO 60 MPH ARE POSSIBLE ALONG AND EAST OF A GLASGOW TO CIRCLE TO TERRY LINE. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY STRONG NORTHWEST WINDS WILL IMPACT EASTERN AREAS ON TUESDAY. GUSTS OF 50 TO 60 MPH ARE POSSIBLE ALONG AND EAST OF A GLASGOW TO CIRCLE TO TERRY LINE. WINDS WILL DECREASE BY LATE TUESDAY AFTERNOON. THOUGH PRECIPITATION WILL TAPER OFF TUESDAY...THE THREAT OF FLOODING WILL CONTINUE THROUGH AT LEAST THE MIDDLE OF THE WEEK. .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.
Flooding occurred on several streams as 1.5 inches of rain fell on saturated soils. This included Beaver Creek.
Flooding occurred on several streams as up to 1.5 inches of rain fell on saturated soils. These included Willow, Cherry, Antelope and Porcupine Creeks.
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, May 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: 322412, 322413.