Thunderstorms formed along and ahead of a very strong cold front and deep upper level low. Some storms became severe producing strong wind gusts.
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 BIS wrote it up.
Thunderstorms formed along and ahead of a very strong cold front and deep upper level low. Some storms became severe producing strong wind gusts.
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 Bismarck, ND wrote its last area forecast discussion before the first event at Jul 27, 12:52 PM MST, 3 hours 38 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BISMARCK ND 252 PM CDT MON JUL 27 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 233 PM CDT MON JUL 27 2015 CONSIDERABLE SUNSHINE ALLOWING FULL HEATING ACROSS MUST OF WEST AND CENTRAL NORTH DAKOTA THIS AFTERNOON. DEWPOINTS INTO THE MID 60S TO THE MID 70S. NAM BUFKIT SOUNDINGS HAVE 4000+ CAPE WITH 20-30 KTS BULK SHEAR ACROSS WEST AND CENTRAL NORTH DAKOTA. WAITING FOR CAP TO ERODE. HEAVY RAIN AMOUNTS IN THE THUNDERSTORM AREAS OF ONE TO NEARLY 2 INCHES MAINLY NORTH. ISOLATED MUCH HIGHER AMOUNTS CERTAINLY POSSIBLE. ON TUESDAY...EXPANDED THE HIGH WIND WATCH EAST THROUGH THE CWA. MODELS DELAYED THE HIGHER WINDS ABOUT 3 TO 6 HOURS. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 233 PM CDT MON JUL 27 2015 THE LONG TERM WILL START WITH WINDY CONDITIONS AND SCATTERED SHOWERS TUESDAY NIGHT THROUGH WEDNESDAY MORNING. THE DEPARTING LOW WILL PRODUCE WRAP AROUND SHOWERS...MAINLY ACROSS NORTHERN NORTH DAKOTA. ADDITIONALLY WITH DOWNSLOPING WINDS AND STRONG CAA WEDNESDAY LOOKS LIKE ANOTHER WINDY DAY...ALBEIT MUCH LESS THAN TUESDAY. THEREAFTER WE WILL SEE A TRANSITION TO NORTHWEST FLOW...WITH RELATIVELY COOL AND DRY CONDITIONS THROUGH THE REST OF THE WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 233 PM CDT MON JUL 27 2015 MAIN HAZARDS TO AVIATION ARE THUNDERSTORMS THIS AFTERNOON WEST SPREADING EAST TONIGHT. ON TUESDAY STRONG WINDS. MAINLY VFR CONDITIONS EXPECTED ALTHOUGH LOCAL MVFR TO IFR POSSIBLE IN THUNDERSTORMS. WEST WINDS INCREASING TO 30 TO 48 KTS AFTER 12Z TUESDAY WESTERN PORTION. STRONG WINDS SPREADING EAST AFTER 18Z. && .BIS WATCHES/WARNINGS/ADVISORIES... HIGH WIND WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING FOR NDZ001>003-009>011-017>021-031>035-040>046. HIGH WIND WATCH FROM TUESDAY AFTERNOON THROUGH TUESDAY EVENING FOR NDZ004-005-012-013-022-023-025-036-037-047-048-050-051. && SHORT TERM...WAA LONG TERM...AJ AVIATION...WAA
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE BISMARCK ND 320 PM CDT MON JUL 27 2015 NDZ001>005-009>013-017>023-025-031>037-040>048-050-051-282030- DIVIDE-BURKE-RENVILLE-BOTTINEAU-ROLETTE-WILLIAMS-MOUNTRAIL-WARD- MCHENRY-PIERCE-MCKENZIE-DUNN-MERCER-OLIVER-MCLEAN-SHERIDAN-WELLS- FOSTER-GOLDEN VALLEY-BILLINGS-STARK-MORTON-BURLEIGH-KIDDER- STUTSMAN-SLOPE-HETTINGER-GRANT-BOWMAN-ADAMS-SIOUX-EMMONS-LOGAN- LA MOURE-MCINTOSH-DICKEY- 320 PM CDT MON JUL 27 2015 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL NORTH DAKOTA...NORTHWEST NORTH DAKOTA...SOUTH CENTRAL NORTH DAKOTA...SOUTHEAST NORTH DAKOTA AND SOUTHWEST NORTH DAKOTA. .DAY ONE...THIS AFTERNOON AND TONIGHT SEVERE THUNDERSTORMS CAN BE EXPECTED ACROSS FAR WESTERN NORTH DAKOTA THIS AFTERNOON. SEVERE THUNDERSTORMS ARE EXPECTED TO MOVE FROM WEST TO EAST ACROSS THE STATE TONIGHT. THE HIGHEST PROBABILITY FOR SEVERE WEATHER WILL BE MONDAY EVENING. LARGE HAIL...DAMAGING WINDS...VERY HEAVY RAIN...AND ISOLATED TORNADOES ARE THE MAIN THREATS. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY STRONG WEST WINDS WILL DEVELOP TUESDAY MORNING SPREADING EAST BY TUESDAY AFTERNOON. WIND GUSTS TO AROUND 60 MPH ARE POSSIBLE. SCATTERED THUNDERSTORMS ARE POSSIBLE WEST AND NORTH TUESDAY. .SPOTTER INFORMATION STATEMENT... PLEASE REPORT ALL HAIL...WINDS OVER 40 MPH...FLOODING...AND TORNADOES...TO THE NATIONAL WEATHER SERVICE AT 701-223-4582 OR VIA SOCIAL MEDIA. WAA
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE BISMARCK ND
455 PM MDT MON JUL 27 2015
NDZ040-043-272330-
SLOPE-BOWMAN-
455 PM MDT MON JUL 27 2015
...A STRONG THUNDERSTORM WILL AFFECT SOUTHWESTERN SLOPE AND WESTERN
BOWMAN COUNTIES...
AT 455 PM MDT...A STRONG THUNDERSTORM WAS 13 MILES WEST OF MUD
BUTTES...OR 25 MILES EAST OF EKALAKA...MOVING NORTHEAST AT 50 MPH.
WIND GUSTS OF 50 TO 55 MPH ARE POSSIBLE WITH THIS STORM.
LOCATIONS IMPACTED INCLUDE...
RHAME...MARMARTH...MUD BUTTES...GRIFFIN...PRETTY BUTTE AND SUNSET
BUTTE.
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 4647 10405 4631 10338 4594 10358 4594 10403
4595 10405
TIME...MOT...LOC 2255Z 204DEG 42KT 4598 10404
HEINERTThe Bismarck radar (KBIS), 245 km away, was scanning. The volume nearest the first event began at 23:31 UTC.
9 thunderstorm wind. Local standard time, as filed.
Strong thunderstorm wind gusts were reported by the public.
Strong thunderstorm wind gusts were reported by a trained spotter.
The strong thunderstorm wind gusts were reported by a trained spotter.
Shingles were blown off a roof, and barn doors were blown out.
A tree blew over onto a garage roof, damaging the roof.
The strong thunderstorm wind gusts were reported by a trained spotter.
The strong thunderstorm wind gusts were reported by the public.
The strong thunderstorm wind gusts were reported by a COOP observer.
The strong thunderstorm wind gusts were reported by a broadcast media partner.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in North Dakota in 2015Every state in 2015This day in weather historyWarnings in North Dakota, July 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: 594998, 594999, 595002, 595004, 595000, 595001, 595003, 595005, 595006.