A weak winter storm brought light amounts of snow to the area except for south central Valley county, where 6 to 7 inches of snow fell.
Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. 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 weak winter storm brought light amounts of snow to the area except for south central Valley county, where 6 to 7 inches of snow fell.
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 Apr 17, 8:10 PM MST, 3 hours 50 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GLASGOW MT 910 PM MDT SUN APR 17 2011 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH TUESDAY... EVENING UPDATE... UPDATE THIS EVENING WAS FOCUSED AROUND RAISING POP GRIDS ACROSS THE CWA TO CHANCE AREA WIDE. MAIN REASON FOR THIS IS LOW CONFIDENCE FROM ERRATIC MODELS AND WHAT APPEARS TO BE SEEDER FEEDER MECHANICS FOR LOCATIONS THAT ARE RECEIVING PRECIPITATION. LOOKING UPWINDS WHILE RADAR IS DOWN IN TFX... OBS SITES SUCH AS LEWISTOWN AND HAVRE ARE REPORTING SPORADIC SNOW SHOWERS AS WELL ADDING TO RAISING POPS. GAH PREVIOUS SHORT TERM DISCUSSION... SHORT TERM FORECAST LOOKS WINTERY OVER THE NEXT FEW DAYS WITH ACCUMULATING SNOWFALL. THE TRICK IS HOW MUCH SNOW IS GOING TO ACCUMULATE AS THE NEXT SYSTEM MOVE THROUGH MONDAY NIGHT INTO WEDNESDAY MORNING? FOR TONIGHT WE ARE LOOKING AT LIGHT ACCUMULATIONS THE REST OF THIS AFTERNOON. THE SNOWFALL WILL TAPER OFF FROM WEST TO EAST LATE THIS EVENING AS SURFACE TROUGH SHIFTS WESTWARD. ALTHOUGH THERE WILL STILL BE ENOUGH MOISTURE OVER RUNNING THE SURFACE TROUGH PLUS ENOUGH LIFT TO CONTINUE TO PRODUCE LIGHT SNOWFALL OVERNIGHT INTO MONDAY MORNING. MONDAY AFTERNOON INTO WEDNESDAY MORNING ANOTHER STRONG SYSTEM WILL MOVE THROUGH THE REGION BRINGING THE POTENTIAL FOR SIGNIFICANT SNOWFALL SOUTH OF THE MISSOURI RIVER. THE ECMWF MODEL HAS BEEN CONSISTENT OVER THE LAST FEW MODELS RUNS PUTTING THE QPF ACROSS OUR SOUTHERN ZONES. THE LATEST GFS RUN HAS SHIFTED THE PRECIP MORE TO THE NORTH THEN WHAT YESTERDAYS 12Z GFS RUN HAD. SO DECIDED TO BASE THE FORECAST MORE ON THE ECMWF THEN THE OTHER MODELS. ALTHOUGH BOTH THE GFS AND NAM ARE FAIRLY CLOSE TO THE ECMWF WITH THE BULK OF PRECIPITATION OVER SOUTHERN MONTANA. THE STORM WILL MOVE INTO WESTERN MONTANA AS A SHORTWAVE TROUGH SLIDES ACROSS THE NORTHERN ROCKIES AND INTO WESTERN MONTANA MONDAY NIGHT. A CLOSED 500 MB AND 700 MB CIRCULATION WILL DEVELOP WITH THIS SHORTWAVE AND DRAG PACIFIC MOISTURE OVER AN INVERTED SURFACE TROUGH MOVING EASTWARD AHEAD OF THE 500 MB CLOSED LOW. 850 MB TEMPERATURES WILL BE BETWEEN -3*C AND -6*C AS THIS SYSTEM MOVES ACROSS EASTERN MONTANA. THIS MEANS MORE THEN LIKELY THE MAJORITY OF THE PRECIPITATION WILL BE IN THE FORM OF SNOWFALL. PRECIPITATION IN THE FROM OF SNOW WILL START MONDAY NIGHT AND SPREAD EASTWARD ACROSS OUR CWA ON TUESDAY. LAUNCHED A WINTER STORM WATCH FOR MONDAY NIGHT THROUGH TUESDAY NIGHT FOR AREAS SOUTH OF THE MISSOURI RIVER FOR THE POSSIBILITY OF 3 TO 7 INCHES OF HEAVY WET SNOWFALL. THIS OF COURSE DEPENDS ON WHAT MODEL YOU TEND TO BELIEVE. GFS AND NAM WOULD MEAN WINTER WEATHER ADVISORY CONDITIONS SOUTH OF THE MISSOURI RIVER. THE ECMWF WOULD MEAN A WINTER STORM WARNING LEVEL SNOWFALL WITH THE POSSIBILITY OF NEEDING A WINTER WEATHER ADVISORY FOR ZONES NORTH OF THE MISSOURI RIVER. RSMITH .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY... TUESDAY NIGHT WILL CONTINUE TO SEE ONGOING PRECIPITATION ACROSS THE EAST AND SOUTHEAST FROM THE EXITING STORM SYSTEM. WEDNESDAY INTO WEDNESDAY NIGHT WILL SEE A BRIEF DECREASE IN PRECIPITATION POTENTIAL AS WEAK RIDGING BUILDS INTO NORTHEAST MONTANA AHEAD OF ANOTHER DIGGING PACIFIC TROUGH. THURSDAY INTO SATURDAY SAID PACIFIC TROUGH WILL SLIDE THROUGH BRINGING ANOTHER ROUND OF SCATTERED RAIN AND SNOW SHOWERS. BIGGEST CHANGES WERE TO INCREASE POPS FOR THE EXITING SYSTEM THURSDAY NIGHT. ALSO TWEAKED CHANCES FOR PRECIP WITH THE PACIFIC TROUGH FOR LATE IN THE WEEK. CONTINUED THE BELOW NORMAL TEMPS THROUGH THE PERIOD. GILCHRIST PREVIOUS LONG TERM DISCUSSION...TUESDAY NIGHT THROUGH THURSDAY NIGHT... ANTICIPATED A WEAK RIDGE TO BUILD AND MOVE THROUGH THE REGION DURING THIS SET OF PERIODS AS A SHORTWAVE EJECTS OFF INTO THE GREAT LAKES. A SYNOPTIC SCALE TROUGH WILL ALSO SET UP OFF THE COASTLINES OF THE PACIFIC NORTHWEST AND BRITISH COLUMBIA. A DEEP COLD AND VIGOROUS SHORTWAVE EXISTS ACROSS THE NORTHERN TIER OF THE CANADIAN PRAIRIE PROVINCES AND MODELS ARE HAVING A TOUGH TIME NAILING DOWN WHETHER THIS COLD AIR WILL SURGE SOUTH OR PRESS TO THE EAST. THIS WILL GENERATE SOME UNCERTAINTY FOR THE NEXT SET OF PERIODS. THURSDAY THROUGH FRIDAY... PACIFIC NORTHWEST TROUGH MOVES THROUGH THE HIGH PLAINS OF MONTANA GENERATING THE CHANCE FOR ISOLATED TO SCATTERED SHOWERS EACH AFTERNOON. THE DIFFICULT PART HERE IS DETERMINING WHETHER COLD AIR FROM UP NORTH WILL SURGE SOUTH AND LOWER DAYTIME HIGHS AND OVERNIGHT LOWS OR NOT. CURRENTLY GOING WITH A TEMPERATURE HOLD IN THE PATTERN AS DO NOT BELIEVE THE COLD AIR WILL BE ABLE TO DRIVE FAR ENOUGH SOUTH TO IMPACT NORTHERN MONTANA BEFORE BEING BRUSHED OFF TO THE EAST. FRIDAY NIGHT ONWARDS... IN BOTH THE GFS AND EC A LARGE SCALE SYNOPTIC RIDGE BUILDS INTO THE REGION. AVERAGE CONFIDENCE IN THIS FEATURE FORMING IS ANTICIPATED AS THE RIDGE IS LARGE SCALE AND CONSISTENT ACROSS THE MODELS... BUT IT IS ALSO FOLLOWING A SHAKY GROUND OF THE COLD FRONT/S PASSAGE. THIS PERIOD SHOULD BE MARKED WITH PARTLY CLOUDY TO CLEAR SKIES AND WARMING TEMPERATURES. GAH && .AVIATION... MVFR CEILINGS WILL CONTINUE THROUGH THE NIGHT FOR GLASGOW...BUT IFR AND EVEN LIFR CEILINGS CAN BE EXPECTED FOR SIDNEY WOLF POINT AND ESPECIALLY GLENDIVE. CEILINGS SHOULD RISE MONDAY BUT SNOW SHOWERS MAY KNOCK VISIBILITIES DOWN AS THEY MOVE IN FROM THE WEST. JAMBA && .HYDROLOGY... MODERATE TO MAJOR FLOODING CONTINUES ON THE MILK RIVER. THE RIVER AT THE BJORNBERG BRIDGE NEAR SACO CRESTED FRIDAY AT JUST BELOW 22 FEET AND HAS FALLEN BETTER THAN A FOOT SINCE THEN. THE RIVER IS EXPECTED TO CONTINUE TO DROP THROUGH TONIGHT...BEFORE AGAIN RISING TO MODERATE FLOOD STAGE BY TUESDAY AFTERNOON THANKS TO RUNOFF FROM FRENCHMAN CREEK. IT MAY FALL BELOW FLOOD STAGE LATE AFTERNOON ON THE 21ST. AT TAMPICO THE RIVER CRESTED NEAR 28 FEET FRIDAY EVENING AND IS FALLING VERY SLOWLY. THAT BEING SAID THE RIVER AT TAMPICO WILL REMAIN ABOVE MAJOR FLOOD STAGE. SATURDAY AFTERNOON THE MILK RIVER AT GLASGOW CRESTED JUST ABOVE MAJOR FLOOD AT 32.84 FEET...AND WILL CONTINUE TO SLOWLY FALL THROUGH MIDWEEK. THIS WAS THE THIRD HIGHEST CREST IN HISTORY. NASHUA IS EXPECTED TO CONTINUE ITS STEADY CLIMB AND CREST SOMETIME EARLY TUESDAY ABOVE THE 30 FOOT MAJOR FLOOD STAGE. WATER LEVELS ON THE MILK RIVER FROM HINSDALE TO NASHUA WILL REMAIN ABOVE FLOOD STAGE THROUGH AT LEAST NEXT WEEKEND. THE AREAL FLOOD WARNING FOR EASTERN PHILLIPS AND MOST OF VALLEY COUNTIES CONTINUES. WATER LEVELS ON THE UPPER REACHES OF CREEKS FLOWING INTO THE MILK VALLEY FROM THE SOUTH HAVE SUBSIDED...WITH FLOODING CONTINUING WHERE THESE CREEKS ENCOUNTER THE MILK RIVER. THIS INCLUDES BEAVER CREEK FROM THE SACO FLATS THROUGH HINSDALE AND ANTELOPE...BRAZIL AND WILLOW CREEKS NEAR GLASGOW. FLOODING IS ALSO OCCURRING ON THE STREAMS FEEDING INTO THE MILK RIVER FROM THE NORTH...INCLUDING ROCK...BEAR AND BUGGY CREEKS. THE FRENCHMAN RIVER AT THE CANADIAN BORDER IS ABOVE THE FLOOD STAGE OF 12 FEET AND IS EXPECTED TO CONTINUE TO FLUCTUATE ABOVE FLOOD STAGE THROUGH THE WEEK AS RUNOFF CONTINUES. AREAS OF NORTHERN VALLEY AND PHILLIPS COUNTY STILL HAVE SIGNIFICANT AMOUNTS OF SNOW COVER. AN AREAL FLOOD ADVISORY WAS ISSUED FOR THE SOUTHERN PART OF THE BIG MUDDY DRAINAGE IN ROOSEVELT AND SHERIDAN COUNTIES AS LOCAL OFFICIALS AND THE SHERIFFS DEPT REPORTED THE BIG MUDDY BEING OVER AREA ROADS. && .GLASGOW WATCHES/WARNINGS/ADVISORIES... WINTER STORM WATCH FROM LATE MONDAY NIGHT THROUGH LATE TUESDAY NIGHT FOR PETROLEUM...GARFIELD...MCCONE...RICHLAND...DAWSON... PRAIRIE...WIBAUX. && WEATHER.GOV/GLASGOW
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GLASGOW MT 313 PM MDT SUN APR 17 2011 MTZ016-017-059>061-181100- CENTRAL AND SOUTHEAST PHILLIPS-CENTRAL AND SOUTHERN VALLEY- NORTHERN PHILLIPS-SOUTHWEST PHILLIPS-NORTHERN VALLEY- 313 PM MDT SUN APR 17 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...THIS AFTERNOON AND TONIGHT FLOOD WARNINGS REMAIN IN EFFECT FOR THE MILK RIVER FROM BJORNBERG BRIDGE NEAR SACO TO NASHUA AND FOR NUMEROUS SMALL STREAMS ACROSS NORTHERN PHILLIPS AND VALLEY COUNTIES DUE TO CONTINUED SNOW MELT. ABOVE FREEZING TEMPERATURES MOST OF THIS WEEK WILL CONTINUE MELTING THE REMAINING SNOW PACK AND SUPPORT CONTINUED FLOOD PROBLEMS. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY A LOW PRESSURE SYSTEM WILL CROSS THE NORTHERN ROCKIES AND INTO SOUTHERN MONTANA MONDAY NIGHT THROUGH EARLY WEDNESDAY MORNING. LIGHT ACCUMULATING SNOWFALL IS POSSIBLE. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ018-020-181100- DANIELS-WESTERN ROOSEVELT- 313 PM MDT SUN APR 17 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...THIS AFTERNOON AND TONIGHT LIGHT ACCUMULATIONS OF SNOW WILL BE POSSIBLE THROUGH THIS EVENING. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY A LOW PRESSURE SYSTEM WILL CROSS THE NORTHERN ROCKIES AND INTO SOUTHERN MONTANA MONDAY NIGHT THROUGH EARLY WEDNESDAY MORNING. LIGHT ACCUMULATING SNOWFALL IS POSSIBLE. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ021>027-181100- PETROLEUM-GARFIELD-MCCONE-RICHLAND-DAWSON-PRAIRIE-WIBAUX- 313 PM MDT SUN APR 17 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...MONDAY THROUGH SATURDAY A LOW PRESSURE SYSTEM WILL CROSS THE NORTHERN ROCKIES AND INTO SOUTHERN MONTANA MONDAY NIGHT THROUGH EARLY WEDNESDAY MORNING. SIGNIFICANT ACCUMULATING SNOWFALL LOOKS TO BE A GROWING THREAT WITH THIS SYSTEM. A WINTER STORM WATCH IS IN EFFECT. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ019-062-181100- SHERIDAN-EASTERN ROOSEVELT- 313 PM MDT SUN APR 17 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...THIS AFTERNOON AND TONIGHT A FLOOD ADVISORY IS IN EFFECT FOR THE LOWER PORTION OF BIG MUDDY CREEK IN SOUTHERN SHERIDAN AND EASTERN ROOSEVELT COUNTIES. WATER IS OVER AREA ROADS AS THE BIG MUDDY CREEK CONTINUES TO RUN HIGH. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY A LOW PRESSURE SYSTEM WILL CROSS THE NORTHERN ROCKIES AND INTO SOUTHERN MONTANA MONDAY NIGHT THROUGH EARLY WEDNESDAY MORNING. LIGHT ACCUMULATING SNOWFALL IS POSSIBLE. .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.
1 winter storm. Local standard time, as filed.
Observers around Hinsdale (and one 20 miles north of Saco) observed 6 to 7 inches of snow total from this system.
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, April 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: 290229.