Flash flooding occurred in southern Tripp County after three to five inches of rain fell in less than six hours south of Colome.
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 UNR wrote it up.
Flash flooding occurred in southern Tripp County after three to five inches of rain fell in less than six hours south of Colome.
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 Rapid City, SD wrote its last area forecast discussion before the first event at Sep 22, 11:07 PM CST, 53 minutes earlier.
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY NATIONAL WEATHER SERVICE RAPID CITY SD 1107 PM MDT TUE SEP 22 2015 .SHORT TERM...THIS EVENING THROUGH WEDNESDAY NIGHT ISSUED AT 220 PM MDT TUE SEP 22 2015 REMNANT TROPICAL IMPULSE CONTINUES TO SHIFT NE TODAY WHILE THE REGION REMAINS UNDER MOIST LL SE FLOW. CLOUDS COMBINED WITH MOIST UPSLOPE FLOW HAS STRONGLY LIMITED T RISES TODAY ACROSS THE FA AND HAVE CONTINUED TO TREND HIGHS DOWN IN LINE WITH TRENDS. PRESSURE FALLS COMBINED WITH INCREASING DEEP LAYER MOISTURE UNDER STEEP MID LEVEL LAPSE RATES AND A LLJ WILL SUPPORT INCREASING CHANCES FOR SHOWERS OVER CENTRAL SD TONIGHT...POSSIBLY SKIRTING PORTIONS OF WESTERN SD. OVERLAP OF STRONGEST DEEP LAYER ASCENT/MOISTURE TRANSPORT AND LL CONVERGENCE WILL REMAIN MOSTLY EAST OF THE FA...WITH SCENTRAL SD SEEING THE BEST CHANCES FOR RAIN. AMPLE LL MOISTURE IN UPSLOPE FLOW MAY ALSO SUPPORT FOG DEVELOPMENT OVER THE SOUTHERN THIRD TONIGHT HENCE...HAVE ADDED A PATCHY FOG MENTION. WED...BULK OF FORCING WILL SHIFT OVER CENTRAL/EASTERN SD WITH SHOWERS EXPECTED OVER THE FAR EASTERN FA...ESP SCENTRAL SD. HAVE RAISED POPS TO CAT THERE. THUNDER ALSO POSSIBLE GIVEN SUFFICIENT INSTABILITY PROGGED IN FORECAST MODELS. MEAN QPF PROGS SUGGEST AROUND AN INCH OF RAIN WILL BE POSSIBLE FROM WINNER EAST GIVEN AMPLE MOISTURE WITH THIS SYSTEM. ADJUSTED TEMPS DOWN ACROSS THE SE HALF WHERE CLOUDS AND POSSIBLE RAIN WILL LIMIT HIGHS. IT COULD CERTAINLY END UP BEING COOLER THAN CURRENT FORECAST NUMBERS OVER SCENTRAL SD. OTHERWISE...THE NW HALF WILL SEE DRY CONDS WITH WARM TEMPS...ESP OVER NE WY. SHOWERS WILL BEGIN TO SHIFT EAST OVER SCENTRAL SD WED NIGHT...WITH DRY CONDS ALL OTHER PLACES. .LONG TERM...THURSDAY THROUGH TUESDAY ISSUED AT 220 PM MDT TUE SEP 22 2015 A FEW SHOWERS AND THUNDERSTORMS MAY LINGER ACROSS SOUTH CENTRAL SD THURSDAY...BUT THEN DRY WEATHER IS EXPECTED INTO THE WEEKEND AS UPPER LEVEL RIDGING BUILDS IN BEHIND THE DEPARTING WAVE. TEMPS WILL GRADUALLY RISE THURSDAY THROUGH SATURDAY AS THE THERMAL RIDGE SLOWLY SHIFTS EASTWARD OVER THE REGION...WITH WELL ABOVE AVERAGE TEMPS OVER WESTERN PORTIONS OF THE CWA ON FRIDAY AND ACROSS THE ENTIRE AREA ON SATURDAY AND SUNDAY. SOME MODEL DISAGREEMENT ENTERS THE PICTURE LATE IN THE WEEKEND AND EARLY NEXT WEEK WITH REGARD TO A POSSIBLE BREAKDOWN OF THE RIDGE. GFS MORE AGGRESSIVE WITH THIS POSSIBILITY...BRINGING A TROF ACROSS THE REGION EARLY IN THE WEEK...WHILE THE EC KEEPS THE SYSTEM FURTHER NORTH AND BUILDS THE RIDGE BACK UP EARLY IN THE WEEK. WILL LEAN TOWARD THE GFS AT THIS POINT AND KEEP CHANCES FOR PCPN IN THE FORECAST FOR SUNDAY NIGHT INTO TUESDAY...WITH THE BEST CHANCES LOOKING TO BE SUNDAY NIGHT INTO MONDAY. TEMPS WILL DROP BACK AT LEAST A LITTLE EARLY NEXT WEEK...BUT WILL BE BACK TO MORE SEASONABLE LEVELS BY TUESDAY IF THE GFS IS CORRECT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1103 PM MDT TUE SEP 22 2015 MVFR/LOCAL IFR/LIFR CIGS WILL COVER MOST OF WESTERN SD THROUGH MIDDAY WEDNESDAY WHEN IT WILL THEN SLOWLY ERODE FROM THE WEST IN THE AFTERNOON. AREAS IFR VSBYS DUE TO BR WILL OCCUR NEAR THE NE/WY BORDER. IFR CIGS WILL PUSH INTO NORTHEAST WY OVERNIGHT INTO EARLY WEDNESDAY MORNING AND THEN QUICKLY BURN OFF. SHRA/TSRA WILL CONTINUE OVER CENTRAL SD THROUGH WEDNESDAY AFTERNOON WITH LOCAL LIFR CONDITIONS DUE TO ST/HEAVY RAIN. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && SHORT TERM...JC LONG TERM...26 AVIATION...HELGESON
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE RAPID CITY SD 243 AM MDT TUE SEP 22 2015 SDZ001-002-012>014-024>032-041>044-046-047-049-072>074-WYZ054>058- 071-231400- HARDING-PERKINS-BUTTE-NORTHERN MEADE CO PLAINS-ZIEBACH- NORTHERN BLACK HILLS-NORTHERN FOOT HILLS-RAPID CITY- SOUTHERN FOOT HILLS-CENTRAL BLACK HILLS-SOUTHERN BLACK HILLS- CUSTER CO PLAINS-PENNINGTON CO PLAINS-HAAKON-FALL RIVER-SHANNON- JACKSON-BENNETT-MELLETTE-TODD-TRIPP-STURGIS/PIEDMONT FOOT HILLS- SOUTHERN MEADE CO PLAINS-HERMOSA FOOT HILLS-NORTHERN CAMPBELL- SOUTHERN CAMPBELL-WESTERN CROOK-WYOMING BLACK HILLS-WESTON- NORTHEASTERN CROOK- 243 AM MDT TUE SEP 22 2015 /343 AM CDT TUE SEP 22 2015/ THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN SOUTH DAKOTA AND NORTHEASTERN WYOMING. .DAY ONE...TODAY AND TONIGHT ISOLATED THUNDERSTORMS ARE POSSIBLE OVER PARTS OF WESTERN AND CENTRAL SOUTH DAKOTA TONIGHT. SEVERE THUNDERSTORMS ARE NOT EXPECTED. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY THERE IS A SLIGHT CHANCE OF THUNDERSTORMS OVER PARTS OF CENTRAL SOUTH DAKOTA ON WEDNESDAY AND THURSDAY. SEVERE THUNDERSTORMS ARE NOT EXPECTED. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY. && STAY TUNED TO NOAA WEATHER RADIO FOR FURTHER DETAILS OR UPDATES... OR CHECK OUR WEB SITE AT WEATHER.GOV/RAPIDCITY
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE RAPID CITY SD
1027 PM CDT TUE SEP 22 2015
SDZ046-047-049-230415-
TODD SD-MELLETTE SD-TRIPP SD-
1027 PM CDT TUE SEP 22 2015
...SIGNIFICANT WEATHER ADVISORY FOR TODD...SOUTHEASTERN MELLETTE AND
TRIPP COUNTIES UNTIL 1115 PM CDT...
AT 1027 PM CDT...DOPPLER RADAR WAS TRACKING A LINE OF STRONG
THUNDERSTORMS ALONG A LINE EXTENDING FROM 7 MILES SOUTH OF BURKE TO
NEAR ROSEBUD...AND MOVING NORTHEAST AT 15 MPH.
NICKEL SIZE HAIL WILL BE POSSIBLE WITH THESE STORMS.
LOCATIONS IMPACTED INCLUDE...
WINNER...MISSION...ROSEBUD...SAINT FRANCIS...COLOME...OKREEK...SPRING
CREEK...WOOD...CARTER...MILLBORO...MOSHER...KEYAPAHA...WITTEN...
LAKEVIEW...WEWELA...LITTLEBURG...CLEARFIELD AND HIDDEN TIMBER.
LAT...LON 4299 9954 4300 10111 4356 10082 4339 9953
4300 9954
TIME...MOT...LOC 0327Z 218DEG 12KT 4308 9934 4329 10090
HELGESONSPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE RAPID CITY SD
1150 PM CDT TUE SEP 22 2015
SDZ046-049-230530-
MELLETTE SD-TRIPP SD-
1150 PM CDT TUE SEP 22 2015
...SIGNIFICANT WEATHER ADVISORY FOR EAST CENTRAL MELLETTE AND WEST
CENTRAL TRIPP COUNTIES UNTIL 1230 AM CDT...
AT 1150 PM CDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM
NEAR MOSHER...OR 20 MILES EAST OF WHITE RIVER...MOVING NORTHEAST AT
15 MPH.
NICKEL SIZE HAIL WILL BE POSSIBLE WITH THIS STORM.
LOCATIONS IMPACTED INCLUDE...
MOSHER.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY LEAD
TO FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.
&&
LAT...LON 4351 10043 4370 10023 4369 10021 4370 10020
4371 10018 4350 10014 4343 10035
TIME...MOT...LOC 0450Z 232DEG 13KT 4351 10033
HELGESONSPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE RAPID CITY SD
1224 AM CDT WED SEP 23 2015
SDZ049-230630-
TRIPP SD-
1224 AM CDT WED SEP 23 2015
...SIGNIFICANT WEATHER ADVISORY FOR NORTHERN TRIPP COUNTY UNTIL 130
AM CDT...
AT 1224 AM CDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM 7
MILES NORTH OF WITTEN...OR 17 MILES NORTHWEST OF WINNER...MOVING
NORTHEAST AT 20 MPH.
NICKEL SIZE HAIL WILL BE POSSIBLE WITH THIS STORM.
LOCATIONS IMPACTED INCLUDE...
IDEAL.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY LEAD
TO FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.
&&
LAT...LON 4354 9963 4348 10013 4357 10020 4371 10004
4371 10001 4369 10000 4369 9993 4370 9990
4367 9987 4370 9986 4369 9984 4370 9980
TIME...MOT...LOC 0524Z 240DEG 17KT 4355 10012
HELGESONThe North Platte radar (KLNX), 158 km away, was scanning. The volume nearest the first event began at 05:59 UTC.
1 flash flood. Local standard time, as filed.
Water overflowed 290th Street west of Highway 183. Dry stock ponds quickly filled and gravel was washed off some roads in southern Tripp County.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in South Dakota in 2015Every state in 2015This day in weather historyWarnings in South Dakota, September 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: 597447.