In conjunction with the High Wind Episode of the same day, an isolated thunderstorm grew strong enough to produce severe winds.
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.
In conjunction with the High Wind Episode of the same day, an isolated thunderstorm grew strong enough to produce severe winds.
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 29, 8:06 PM MST, 1 hour 34 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GLASGOW MT 906 PM MDT MON APR 29 2013 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH WEDNESDAY... UPDATED FORECAST TO COVER CURRENT RADAR TRENDS AND SHORT TERM PRECIPITATION EXPECTATIONS. WINDS REMAIN STRONG AROUND THE AREA THIS EVENING. EXPECT SOME DECLINE IN SURFACE WIND WITH THE CESSATION OF SURFACE HEATING...HOWEVER...BUFR SOUNDINGS DO NOT SHOW A GREAT DEAL OF DE-COUPLING OF THE SURFACE LAYER. AS 850MB WINDS REMAIN STRONG OVER NIGHT AND INTO TOMORROW...WILL WAIT TO SEE SURFACE WINDS SHOW AN ACTUAL WIDESPREAD DECLINE INTO THE 20S BEFORE EXPIRING THE HIGH WIND PRODUCT...WHICH STILL RUNS UNTIL MIDNIGHT. DID EXPIRE THE FIRE WX HEADLINE AS THE SURFACE IS COOLING SUFFICIENTLY TO PLACE RH VALUES IN THE 40 TO 50 PERCENT RANGE OVER THE AREA. WINDS WILL REMAIN STRONG THROUGH TUESDAY...BUT TEMPERATURES WILL BE MUCH COOLER. AS ALL MODEL GUIDANCE NOW SHOWS WINDS THROUGH SUNSET TUESDAY TO BE AT OR ABOVE 20KTS...LAKE WIND ADVISORY HAS BEEN EXTENDED THROUGH TUESDAY. LARGE SURFACE LOW IS GRADUALLY DESCENDING SOUTHEAST THROUGH EASTERN MONTANA AND THE DAKOTAS. MAJOR COLD FRONT IS EXPECTED BETWEEN MIDNIGHT AND 6AM TUESDAY MORNING. WITH FRONT...WINDS WILL VEER TO BECOME MORE NORTHERLY AND WILL ADVECT COLD AIR INTO THE REGION. LEADING TO POTENTIAL FROST TUESDAY MORNING AND A HARDER FREEZE WEDNESDAY MORNING. MARTIN PREVIOUS DISCUSSION... ACTIVE WEATHER DAY CONTINUES ACROSS NORTHEAST MONTANA. A FRONTAL SYSTEM PASSING THROUGH THE CWA IS BEGINNING TO INITIATE CONVECTIVE SHOWERS AND STORMS WHICH ARE PUSHING FROM NORTHWEST TO SOUTHEAST. SOME OF THESE STORMS WILL ASSIST IN BRINGING DOWN VERY STRONG BURSTS OF WIND FROM ALOFT DOWN TO THE SURFACE. IN ADDITION...LATEST NAM AND GFS CONTINUE TO SHOW 40-45 KT WIND SPEEDS AT 850MB BETWEEN ABOUT 00Z AND 06Z THIS EVENING. THIS IS WHEN THE STRONGEST WINDS CAN BE EXPECTED ACROSS THE CWA. GIVEN WELL MIXED BOUNDARY LAYER DEVELOPING...GOOD LAPSE RATES...AND CAA THIS EVENING...MANY LOCATIONS SHOULD CONTINUE TO SEE WINDS INCREASING THROUGH THE REST OF THE AFTERNOON AND EVENING. WILL LEAVE THE HIGH WIND WARNING AND LAKE WIND ADVISORY AS IS GIVEN THESE ARGUMENTS. STILL FEEL LIKE THE STRONGEST WINDS ARE YET TO COME. LATER TONIGHT THE WINDS WILL BEGIN TO DIMINISH...BUT IT WILL REMAIN BREEZY THROUGH THE OVERNIGHT. TUESDAY THROUGH WEDNESDAY...UPPER TROUGH EXPECTED TO LINGER OVER THE REGION...SO KEPT SLIGHT CHANCE POPS IN THE GRIDS WITH A CHANCE OF SHOWER ACTIVITY. TEMPERATURES ALSO WILL BE BELOW AVERAGE GIVEN LOWERING THICKNESSES. BY WEDNESDAY THE TROUGH AXIS SWINGS THROUGH...RESULTING IN DRIER CONDITIONS AND MODESTLY HIGHER TEMPERATURES. HOWEVER...AFTERNOON HIGHS WILL REMAIN BELOW SEASONAL NORMALS. MALIAWCO .LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY... AS DISCUSSED BELOW THE FORECAST MODELS CONTINUE TO STRUGGLE THROUGHOUT THE EXTENDED FORECAST...THUS CONFIDENCE REMAINS SHAKY. ONLY TWEAKS MADE WERE TO RAISE POPS FOR FRIDAY INTO FRIDAY NIGHT AS ALL OF THE MAJOR MODELS DEPICT A DISTURBANCE IN A NORTHWEST FLOW ALOFT CROSSING OUR WESTERN ZONES. ALSO TRENDED POPS TOWARD CLIMATOLOGY FOR MONDAY AND MONDAY NIGHT AS THE OFTEN BETTER PERFORMING ECMWF AND THE GEM CONTINUE TO SHOW A LARGE LOW PRESSURE SYSTEM IMPACTING THE AREA WHILE THE GFS AND DGEX ARE WARM AND RIDGY. GIVEN THE LARGE SPREAD AND TOTAL LACK OF CONFIDENCE FELT CLIMO WAS THE WAY TO GO. GILCHRIST PREVIOUS LONG TERM DISCUSSION...THE EXTENDED FORECAST HAS A MUCH BELOW CONFIDENCE FORECAST... ESPECIALLY FOR NEXT WEEKEND INTO A WEEK FROM TODAY. MODEL SPREADS AND TRENDS ARE ALL OVER THE PLACE FOR NORTHEAST MONTANA WHICH LEADS TO THE BELOW NORMAL CONFIDENCE FORECAST. THE MAIN CULPRIT IS A DEVELOPING CUT OFF LOW OVER THE MID MISSISSIPPI RIVER VALLEY THAT THE GFS AND EC HANDLE IN VERY DIFFERENT WAYS FOR THE EXTENDED. UPPER LOWS ARE UNPREDICTABLE ON MOVEMENT AND CAN LEAD TO MANY DIFFERENT OUTCOMES FOR THE LATER PERIODS. THEREFORE KEPT POPS FAIRLY LOW THROUGH THE PERIOD WITH ONLY SOME SHOWERS FOR FRIDAY NIGHT AND SATURDAY AS BOTH MODELS TRY TO DEVELOP A CENTRAL MONTANA LEE TROUGH. TEMPERATURES HELD THEM AROUND TO SLIGHTLY BELOW NORMAL...HOWEVER THE ENVELOPE OF POSSIBILITIES RANGES VASTLY. EXAMPLE ON MONDAY MORNING THE RANGE OF LOWS IN THE MODELS FOR GLASGOW RUN FROM 31 DEGREES TO 54 FOR A MORNING LOW AND HIGHS 44 TO 74 THAT AFTERNOON. PROTON && .AVIATION... MAINLY VFR THIS EVENING INTO LATE TONIGHT. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE OVER NORTHEAST MONTANA THIS EVENING...POSSIBLY LOWERING CONDITIONS BRIEFLY TO MVFR. AN MVFR STRATUS DECK WILL PUSH INTO THE REGION OUT OF CANADA LATE TONIGHT INTO TUESDAY MORNING....BEFORE LIFTING BACK UP TO VFR LEVELS BY LATE TUESDAY MORNING. STRONG GUSTY WESTERLY WINDS WILL CONTINUE INTO THIS EVENING...BEFORE GOING MORE NORTHWESTERLY BEHIND A COLD FRONT LATE TONIGHT. WINDS ARE EXPECTED TO REMAIN FAIRLY STRONG OVERNIGHT INTO TUESDAY...I.E. GREATER THAN 20KTS OR SO. GILCHRIST/GFF && .FIRE WEATHER... STRONG GUSTY WINDS WILL CONTINUE INTO THE EVENING HOURS AS RELATIVE HUMIDITY HOVERS IN THE UPPER TEENS TO 20%S. A COLD FRONT WILL SWEEP THROUGH LATE TONIGHT...COOLING TEMPS AND TURNING WINDS TO THE NORTHWEST. WITH THE COOLER TEMPS HUMIDITY WILL RISE ENDING THE CRITICAL CONDITIONS. GUSTY NORTHWEST WINDS ARE EXPECTED TO CONTINUE INTO TUESDAY...BUT HUMIDITY WILL BE HIGHER. && .HYDROLOGY... AS THE SPRING THAW CONTINUES...CREEKS AND STREAMS IN FAR NORTHEAST MONTANA WILL CONTINUE TO RUN HIGH. THE POPLAR RIVER...THE EAST FORK OF THE POPLAR RIVER AND BIG MUDDY CREEK WILL MAINTAIN HIGHER WATER LEVELS INTO EARLY MAY AS THE REMAINING SNOW OVER SOUTHERN SASKATCHEWAN MELTS. MINOR SMALL STREAM AND LOW LAND FLOODING WILL BE POSSIBLE. && .GLASGOW WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING UNTIL MIDNIGHT MDT TONIGHT FOR CENTRAL AND SOUTHEAST PHILLIPS...PETROLEUM...GARFIELD...SOUTHWEST PHILLIPS. LAKE WIND ADVISORY UNTIL 9 PM MDT TUESDAY FOR FORT PECK LAKE. LAKE WIND ADVISORY UNTIL 9 PM MDT TUESDAY FOR FORT PECK LAKE. && WEATHER.GOV/GLASGOW
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GLASGOW MT 915 PM MDT MON APR 29 2013 MTZ018>020-024>027-059-061-062-010315- DANIELS-SHERIDAN-WESTERN ROOSEVELT-RICHLAND-DAWSON-PRAIRIE-WIBAUX- NORTHERN PHILLIPS-NORTHERN VALLEY-EASTERN ROOSEVELT- 915 PM MDT MON APR 29 2013 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...TONIGHT A FRONTAL SYSTEM WILL CONTINUE TO PUSH THROUGH THE AREA THIS EVENING BRINGING A PERIOD OF STRONG WINDS. SUSTAINED WEST TO NORTHWEST WIND SPEEDS OF 25 TO 35 MPH WITH GUSTS TO 45 MPH ARE EXPECTED THROUGH THIS EVENING. THE WINDS SHOULD BEGIN TO DIMINISH AFTER MIDNIGHT. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ016-021-022-060-010315- CENTRAL AND SOUTHEAST PHILLIPS-PETROLEUM-GARFIELD- SOUTHWEST PHILLIPS- 915 PM MDT MON APR 29 2013 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...TONIGHT STRONG GUSTY WINDS ARE EXPECTED TO CONTINUE THROUGH THIS EVENING AS A FRONTAL SYSTEM PUSHES THROUGH THE AREA. WEST TO NORTHWEST WIND SPEEDS OF TO 35 TO 45 MPH ARE EXPECTED WITH GUSTS AS HIGH AS 60 MPH. THE WINDS WILL BEGIN TO DIMINISH AFTER MIDNIGHT. THUS...A HIGH WIND WARNING REMAINS IN EFFECT THROUGH MIDNIGHT TONIGHT. AFTER MIDNIGHT...WINDS WILL REMAIN ABOVE 20 MPH AND A LAKE WIND ADVISORY WILL BEGIN FOR FT. PECK LAKE UNTIL 9PM TUESDAY. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY A LAKE WIND ADVISORY FOR FT. PECK LAKE IS IN EFFECT FOR WINDS OF 15 TO 25 MPH UNTIL 9PM TUESDAY. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. MTZ017-023-010315- CENTRAL AND SOUTHERN VALLEY-MCCONE- 915 PM MDT MON APR 29 2013 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...TONIGHT STRONG WINDS ARE EXPECTED TO CONTINUE THROUGH THIS EVENING AS A FRONTAL SYSTEM PUSHES THROUGH THE REGION. WEST TO NORTHWEST WINDS OF 25 TO 35 MPH WITH GUSTS TO 45 MPH ARE EXPECTED. THE WINDS WILL BEGIN TO DIMINISH AFTER MIDNIGHT. A LAKE WIND ADVISORY IS IN EFFECT THROUGH 9PM TUESDAY. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY A LAKE WIND ADVISORY FOR FT. PECK LAKE IS IN EFFECT FOR WINDS OF 15 TO 25 MPH UNTIL 9PM TUESDAY. .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 527 PM MDT MON APR 29 2013 MTZ019-300030- SHERIDAN- 527 PM MDT MON APR 29 2013 THE NATIONAL WEATHER SERVICE IN GLASGOW HAS ISSUED A SIGNIFICANT WEATHER ADVISORY FOR... NORTHERN SHERIDAN COUNTY IN NORTHEAST MONTANA... UNTIL 630 PM MDT. AT 525 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM NEAR REDSTONE...MOVING EAST AT 45 MPH. HAIL UP TO ONE-HALF INCH IN DIAMETER AND WIND GUSTS UP TO 50 MPH ARE EXPECTED WITH THIS STORM. LOCATIONS IN THE ADVISORY INCLUDE... PLENTYWOOD... OUTLOOK... RAYMOND... WESTBY... THIS STORM MAY INTENSIFY...SO 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 4900 10405 4865 10406 4865 10503 4899 10501 TIME...MOT...LOC 2327Z 253DEG 37KT 4879 10493 GFF WEATHER.GOV/GLASGOW
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE GLASGOW MT 551 PM MDT MON APR 29 2013 MTZ017-300045- VALLEY- 551 PM MDT MON APR 29 2013 THE NATIONAL WEATHER SERVICE IN GLASGOW HAS ISSUED A SIGNIFICANT WEATHER ADVISORY FOR... CENTRAL VALLEY COUNTY IN NORTHEAST MONTANA... UNTIL 645 PM MDT. AT 548 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM OVER HINSDALE AND THE LARB HILLS SOUTH OF HINSDALE...MOVING EAST AT 40 MPH. WIND GUSTS UP TO 50 MPH ARE EXPECTED WITH THIS STORM. LOCATIONS IN THE ADVISORY INCLUDE... TAMPICO... SAINT MARIE... GLASGOW... NASHUA... THIS STORM MAY INTENSIFY...SO 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 4856 10585 4803 10591 4813 10715 4855 10707 TIME...MOT...LOC 2349Z 273DEG 36KT 4842 10697 GFF WEATHER.GOV/GLASGOW
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GLASGOW MT
630 PM MDT MON APR 29 2013
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0617 PM TSTM WND GST GLASGOW 48.20N 106.64W
04/29/2013 M51 MPH VALLEY MT ASOS
MEASURED 51 MPH WIND GUST AT THE GLASGOW ASOS.
&&
RMORGANPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GLASGOW MT
705 PM MDT MON APR 29 2013
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0431 PM NON-TSTM WND GST 5 WNW LANDUSKY 47.92N 108.73W
04/29/2013 M55.00 MPH PHILLIPS MT MESONET
0453 PM NON-TSTM WND GST 11 ENE ZORTMAN 47.96N 108.31W
04/29/2013 M65.00 MPH PHILLIPS MT MESONET
MALTA SOUTH DOT SITE ON US 191 MP 122
0644 PM NON-TSTM WND GST 14 NNW HELL CREEK REC A 47.80N 107.02W
04/29/2013 M60.00 MPH VALLEY MT MESONET
KING COULEE RAWS
&&
GREGFThe Glasgow radar (KGGW), 43 km away, was scanning. The volume nearest the first event began at 04:42 UTC.
1 thunderstorm wind. Local standard time, as filed.
Trained spotters estimated thunderstorm wind gusts of 58 to 60 mph across central portions of Valley County.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2013Every state in 2013This day in weather historyWarnings in Montana, April 2013
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: 448622.