A stationary front and a weak to moderately-unstable atmosphere combined to form strong to severe thunderstorms across portions of northeast Montana.
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 stationary front and a weak to moderately-unstable atmosphere combined to form strong to severe thunderstorms across portions of northeast Montana.
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 Jun 17, 1:22 PM MST, 1 hour 11 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GLASGOW MT 222 PM MDT WED JUN 17 2015 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH FRIDAY... A TROUGH EXTENSION OFF THE HUDSON BAY STACKED LOW SYSTEM ROTATES THROUGH THE PRAIRIE PROVINCES TODAY SENDING A COLD FRONT PLUNGING THROUGH NORTHEAST MONTANA TODAY AND THIS EVENING. THE COLD FRONT WILL FIND AN UNSTABLE ENVIRONMENT WITH WEAK TO MODERATE CONVECTIVE PARAMETERS...WHICH WILL INITIATE A ROUND OF RAIN SHOWERS AND THUNDERSTORMS LATE THIS AFTERNOON AND TONIGHT...SOME OF WHICH MAY BE STRONG ENOUGH TO PRODUCE SMALL HAIL AND GUSTY WINDS. MODELS SHOW GUSTY NORTHERLY WIND BEHIND THE FRONT WHICH PROMPTED THE ISSUE OF A WIND ADVISORY FOR FORT PECK LAKE...MAINLY FOR THIS EVENING. THE ADVISORY BEGINS IN THE AFTERNOON DUE TO THE UNCERTAINTY OF TIMING WITH NORTHERN WINDS. BOTH GFS AND NAM PINPOINT THE NORTHEAST ZONES FOR THE BEST CHANCE FOR WETTING RAINS TONIGHT...AN AREA THAT HAS BEEN MISSED BY RECENT STORMS. SPC INCLUDES OUR AREA IN THE MARGINAL RISK FOR STRONG TS. THURSDAY AND THURSDAY EVENING...THE FRONTAL BOUNDARY RETREATS EAST AS THE UPPER LEVEL RIDGE AXIS CROSSES EASTERN MONTANA. THE RETREATING BOUNDARY ACTS AS A WARM FRONT...NUDGED NORTH BY DESERT AIR PUSHING INTO SOUTHERN MONTANA. BY LATE AFTERNOON EMBEDDED DISTURBANCES IN THE WESTERLY FLOW ALOFT WILL FIND A MODERATELY UNSTABLE ENVIRONMENT AGAIN...WHICH SHIFTS EAST ACROSS THE CWA DURING THE EVENING. THE BEST CHANCE FOR STRONG STORMS LOCALLY WILL BE IN THE EVENING AND STRONG STORMS COULD CONTINUE LATE INTO THE EVENING AND POSSIBLY AFTER MIDNIGHT. SPC HAS PLACED OUR AREA IN THE SLIGHT RISK FOR SEVERE TS WITH LARGE HAIL AND DAMAGING WINDS POSSIBLE. SO WILL KEEP MENTION IN WX GRIDS. THE WARM FRONT MOVES INTO THE DAKOTAS FRIDAY MORNING. SHORTWAVES IN WSW FLOW ALOFT WILL CONTINUE TO BRING CHANCES FOR SHOWERS AND THUNDERSTORMS TO NORTHEAST MONTANA. SCT .LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY... MODIFIED MAINLY DAYS 4 AND 5 (FRIDAY NIGHT THROUGH SUNDAY NIGHT) CLOSER TO MODEL SOLUTIONS. THIS DECREASED WINDS AND HUMIDITIES SATURDAY. TFJ PREVIOUS DISCUSSION... A LARGE AREA OF HOT HIGH PRESSURE IS CENTERED OVER THE DESERT SOUTHWEST AND THE FOUR CORNERS. A PARTIALLY CLOSED LOW SETS OVER BRITISH COLUMBIA. BETWEEN THESE TWO LARGE AIR MASSES ZONAL FLOW RUNS FROM THE PACIFIC NORTHWEST THROUGH NORTHEAST MONTANA AND INTO THE DAKOTAS. THIS PATTERN IS EXPECTED TO STAY ROUGHLY INTACT THROUGHOUT THE LONG RANGE WITH ONLY WEAK RIDGING AND TROUGH BUILDING AND WANING OVER IDAHO. THIS WILL BEND FLOW SLIGHTLY NORTHWEST OR SOUTHWEST RESPECTIVELY... AND ALLOW WEAK SHORTWAVES BY AND INTO EASTERN MONTANA. CONFIDENCE IN THE TIMING OF THESE WAVES IS ABOUT AVERAGE. CURRENTLY WEAK RIDGING LOOKS TO BE AROUND SUNDAY TO MONDAY WHILE THE WEAK TROUGHS AND SHORTWAVES OCCUR ON THE REMAINING PERIODS. THERE IS SOME EVIDENCE TO SUGGEST THAT THE MONDAY NIGHT PERIOD ONWARD MAY HAVE MORE MOISTURE AROUND 700 MB DUE TO ATMOSPHERIC RIVER EFFECT AND THEREFORE INCREASING POPS FROM SLIGHT CHANCE TO CHANCE. BUT THIS COULD QUICKLY CHANGE WITH NEW UPDATES. GAH && .AVIATION... VFR. SHOWERS/TSTORMS ARE MOVING INTO THE AREA THIS AFTERNOON. BEFORE THEY DEPART THIS EVENING...THE HEAVIEST SHOWER MAY BRIEFLY KNOCK VISIBILITY DOWN BELOW VFR. SCATTERED CLOUDS MAY LOWER TO THE MVFR LATE TONIGHT THEN BURN OFF THURSDAY. NORTHEAST WINDS OF 10 TO 20 KTS THIS EVENING WILL FOLLOW IN THE WAKE OF A COLD FRONT. THEN WINDS WILL BECOME LIGHT EAST OVERNIGHT THEN INCREASE FROM THE SOUTHEAST THURSDAY BEFORE ANOTHER CHANCE THUNDERSTORMS MOVE IN LATER IN THE DAY. TFJ && .GLASGOW WATCHES/WARNINGS/ADVISORIES... LAKE WIND ADVISORY UNTIL MIDNIGHT MDT TONIGHT FOR CENTRAL AND SOUTHEAST PHILLIPS...CENTRAL AND SOUTHERN VALLEY...GARFIELD... MCCONE...PETROLEUM. && WEATHER.GOV/GLASGOW
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GLASGOW MT 331 AM MDT WED JUN 17 2015 MTZ016>027-059>062-181100- 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- 331 AM MDT WED JUN 17 2015 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHEAST MONTANA. .DAY ONE...TODAY AND TONIGHT A LAKE WIND ADVISORY IS IN EFFECT FOR FORT PECK LAKE FROM 3 PM THIS AFTERNOON THROUGH MIDNIGHT TONIGHT. NORTH TO NORTHEAST WIND 15 TO 25 MPH ARE EXPECTED. A COLD FRONT WILL MOVE THROUGH NORTHEAST MONTANA THIS AFTERNOON AND EVENING WITH A CHANCE OF THUNDERSTORMS. SOME STORMS MAY BE STRONG WITH SMALL HAIL AND STRONG WINDS. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY A WARM FRONT IS EXPECTED TO MOVE THROUGH NORTHEAST MONTANA THURSDAY AFTERNOON AND EVENING WITH A CHANCE OF THUNDERSTORMS. THERE IS THE POSSIBILITY THAT SOME STORMS MAY BECOME SEVERE WITH LARGE HAIL AND DAMAGING WINDS. .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
246 PM MDT WED JUN 17 2015
MTZ019-172145-
SHERIDAN-
246 PM MDT WED JUN 17 2015
THE NATIONAL WEATHER SERVICE IN GLASGOW HAS ISSUED A
SIGNIFICANT WEATHER ADVISORY FOR...
NORTHEASTERN SHERIDAN COUNTY IN NORTHEAST MONTANA...
UNTIL 345 PM MDT.
AT 240 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM NEAR RAYMOND PORT OF ENTRY...MOVING SOUTHEAST AT
20 MPH.
WIND GUSTS UP TO 40 MPH ARE EXPECTED WITH THIS STORM.
LOCATIONS IN THE ADVISORY INCLUDE...
RURAL AREAS OF NORTHERN SHERIDAN COUNTY...
RURAL AREAS OF EASTERN SHERIDAN COUNTY...
LAT...LON 4889 10404 4876 10404 4862 10422 4898 10479
4901 10475 4901 10429
TIME...MOT...LOC 2046Z 310DEG 17KT 4900 10454
TFJ
WEATHER.GOV/GLASGOWSPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE GLASGOW MT 257 PM MDT WED JUN 17 2015 MTZ016-059-172200- PHILLIPS- 257 PM MDT WED JUN 17 2015 THE NATIONAL WEATHER SERVICE IN GLASGOW HAS ISSUED A SIGNIFICANT WEATHER ADVISORY FOR... CENTRAL PHILLIPS COUNTY IN NORTHEAST MONTANA... UNTIL 400 PM MDT. AT 249 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A STRONG THUNDERSTORM 15 MILES SOUTH OF LORING...MOVING EAST AT 20 MPH. HAIL UP TO ONE-HALF INCH IN DIAMETER AND WIND GUSTS UP TO 40 MPH ARE EXPECTED WITH THIS STORM. LOCATIONS IN THE ADVISORY INCLUDE... RURAL AREAS OF CENTRAL PHILLIPS COUNTY... RURAL AREAS OF EASTERN PHILLIPS COUNTY... LAT...LON 4862 10729 4834 10735 4846 10803 4869 10801 TIME...MOT...LOC 2057Z 282DEG 15KT 4858 10790 TFJ WEATHER.GOV/GLASGOW
The Glasgow radar (KGGW), 79 km away, was scanning. The volume nearest the first event began at 21:31 UTC.
2 thunderstorm wind, 1 hail. Local standard time, as filed.
Trained spotter reported dime-sized hail, 30-40 mph winds, brief wind gusts of 50 mph along with heavy rain.
The Glasgow Airport ASOS site measured a 58 mph wind gust. No impacts were reported from this wind gust.
Public reported 5 power poles snapped by thunderstorm winds. Time based on radar velocity data at this location.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2015Every state in 2015This day in weather historyWarnings in Montana, June 2015
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: 576774, 576775, 576778.