Flash Flood in South Dakota, July 30 to 31, 2013

Name: Flash Flood in South Dakota, July 30 to 31, 2013
Start: 2013-07-30T16:00
End: 2013-07-31T01:00
Location: South Dakota

July 30 to 31, 2013 · NWS UNR · 1 event in 1 county or zone

Heavy rain fell over portions of the Rosebud Reservation. Rain runoff, debris flows from the 2012 Longhorn Fire Complex, and the failure of Omaha Boy Dam caused flash flooding in the Rosebud area of central Todd County.

Where it happened

Every event with a place to put it. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: $60,000
Crop damage: None recorded
Events: 1

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.

What happened

The episode as NWS UNR wrote it up.

What forecasters said that day

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 Jul 30, 2:13 PM CST, 1 hour 47 minutes earlier.

Area forecast discussion, Jul 30, 2:13 PM CST, 1 hour 47 minutes before

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
213 PM MDT TUE JUL 30 2013

.SHORT TERM...THIS EVENING THROUGH WEDNESDAY NIGHT
ISSUED AT 159 PM MDT TUE JUL 30 2013

WATER VAPOR SHOWS SHORT WAVE TROF EXTENDING FROM SWRN ND/NWRN SD
THROUGH SERN WY. ANOTHER SHORT WAVE IS NOTED MOVING THROUGH SCNTRL
MT/NCNTRL WY. AT THE SURFACE...COLD FRONT/BOUNDARY IS PUSHING SWD
THROUGH NWRN SD AND NEARING THE BLKHLS...WHERE A BROAD LOW IS
LOCATED.

THIS AFTN/TONIGHT...EXPECT STORMS TO CONTINUE FIRING THIS AFTN
FROM AROUND THE BLKHLS EWD AS COLD FRONT CONTINUES TO PUSH
SOUTH. MLCAPE OF AROUND 1500J/KG LOCATED FROM NWRN SD INTO NCNTRL
NEB COMBINED WITH EFFECTIVE BULK SHEAR OF 40-60KTS MORE THAN
SUFFICIENT FOR STRONG ROTATING UPDRAFTS IN THAT CORRIDOR...WITH
INSTABILITY AXIS SHIFTING SLOWLY EWD THIS EVE. THE UPSTREAM
SHORTWAVE (NEAR THE BIGHORNS) WILL ALSO AID IN FURTHER DEVELOPMENT
THIS EVENING AND OVERNIGHT. ACTIVITY WILL LIKELY LINGER MUCH OF
THE NIGHT ON THE SD PLAINS FOR BEFORE PUSHING EAST OF THE CWFA.

WEDNESDAY...SURFACE HIGH BUILDS INTO THE CWFA BEHIND THIS
AFTNS/TONIGHTS CONVECTION BRINGING MOSTLY DRY CONDITIONS AND
COOLER TEMPS. RETURN FLOW LATE IN THE DAY IN OUR WRN ZONES WILL
COMBINE WITH MLCAPE AROUND 500J/KG FOR A FEW LATE DAY STORMS IN
NERN WY AND THE BLKHLS...ALTHOUGH SVR STORMS NOT EXPECTED.
ADDITIONAL ACTIVITY IS POSSIBLE OVERNIGHT IN NERN WY AND SWRN SD
AS A WEAK PERTURBATION IN THE WNW FLOW ALOFT MOVES THROUGH.

&&

.LONG TERM...THURSDAY THROUGH TUESDAY
ISSUED AT 159 PM MDT TUE JUL 30 2013

UNSETTLED PATTERN CONTINUES THROUGH THE UPCOMING WEEKEND AS
SERIES OF UPPER LEVEL DISTURBANCES MOVE THROUGH W/NW FLOW BRINGING
CONTINUED CHANCES FOR STORMS THROUGH THE PERIOD. SLIGHTLY COOLER
THAN AVERAGE TEMPS WILL REMAIN THROUGH THIS WEEK WITH A MODEST
WARMING TREND POSSIBLE EARLY NEXT WEEK.

&&

.AVIATION...FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON
ISSUED AT 159 PM MDT TUE JUL 30 2013

STORMS WILL CONTINUE TO DEVELOP THIS AFTERNOON/EVENING.
A FEW STORMS MAY BECOME SEVERE. OTHERWISE...VFR CONDITIONS ARE
EXPECTED.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

SHORT TERM...JOHNSON
LONG TERM...13
AVIATION...13

Hazardous weather outlook, Jul 30, 5:00 AM CST, 11 hours before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE RAPID CITY SD
500 AM MDT TUE JUL 30 2013

SDZ001-002-012>014-024>032-041>044-046-047-049-072>074-WYZ054>058-
071-311300-
BENNETT-BUTTE-CENTRAL BLACK HILLS-CUSTER CO PLAINS-FALL RIVER-HAAKON-
HARDING-HERMOSA FOOT HILLS-JACKSON-MELLETTE-NORTHEASTERN CROOK-
NORTHERN BLACK HILLS-NORTHERN CAMPBELL-NORTHERN FOOT HILLS-
NORTHERN MEADE CO PLAINS-PENNINGTON CO PLAINS-PERKINS-RAPID CITY-
SHANNON-SOUTHERN BLACK HILLS-SOUTHERN CAMPBELL-SOUTHERN FOOT HILLS-
SOUTHERN MEADE CO PLAINS-STURGIS/PIEDMONT FOOT HILLS-TODD-TRIPP-
WESTERN CROOK-WESTON-WYOMING BLACK HILLS-ZIEBACH-
500 AM MDT (600 AM CDT) TUE JUL 30 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN SOUTH DAKOTA AND
NORTHEASTERN WYOMING.

.DAY ONE...TODAY AND TONIGHT

SCATTERED THUNDERSTORMS ARE EXPECTED TODAY AND TONIGHT. THERE IS A
SLIGHT RISK FOR SEVERE THUNDERSTORMS OVER WESTERN AND SOUTH CENTRAL
SOUTH DAKOTA INTO FAR NORTHEASTERN WYOMING. THE PRIMARY THREAT FROM
THESE STORMS WILL BE LARGE HAIL AND DAMAGING WINDS.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THERE IS A CHANCE OF THUNDERSTORMS OVER THE AREA ON WEDNESDAY.
HOWEVER...SEVERE WEATHER IS NOT EXPECTED.

SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP THURSDAY AFTERNOON
AND EVENING. THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER
PORTIONS OF NORTHEASTERN WYOMING AND SOUTHWESTERN SOUTH DAKOTA...
WITH LARGE HAIL AND DAMAGING WIND GUSTS BEING THE PRIMARY THREATS.

CHANCES FOR THUNDERSTORMS CONTINUE THROUGH MONDAY WITH WIDESPREAD
SEVERE THUNDERSTORMS NOT EXPECTED AT THIS TIME. HOWEVER...ISOLATED
SEVERE WEATHER WILL BE POSSIBLE.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AND EVENING.

&&

STAY TUNED TO NOAA WEATHER RADIO FOR FURTHER DETAILS OR UPDATES...
OR CHECK OUR WEB SITE AT WEATHER.GOV/RAPIDCITY

In the hours before

Special weather statement, Jul 30, 2:23 PM CST, 1 hour 37 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE RAPID CITY SD
223 PM MDT TUE JUL 30 2013

SDZ030-031-302115-
CUSTER CO PLAINS SD-PENNINGTON CO PLAINS SD-
223 PM MDT TUE JUL 30 2013

...STRONG THUNDERSTORMS MOVING OVER NORTHEASTERN CUSTER AND
CENTRAL PENNINGTON COUNTIES UNTIL 315 PM MDT...

AT 220 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM NEAR FARMINGDALE...OR 16 MILES SOUTHEAST OF
DOWNTOWN RAPID CITY...MOVING SOUTHEAST AT 20 MPH.

HAIL UP TO THE SIZE OF NICKELS IS EXPECTED WITH THIS STORM.

LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE...
  FARMINGDALE...
  FOLSOM...

THIS STORM MAY INTENSIFY...AND A SEVERE THUNDERSTORM WATCH IS IN
EFFECT FOR THIS AREA.

&&

LAT...LON 4397 10245 4372 10276 4395 10307 4410 10293
TIME...MOT...LOC 2023Z 305DEG 19KT 4398 10290

BUNKERS

Local storm report, Jul 30, 2:36 PM CST, 1 hour 24 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
236 PM MDT TUE JUL 30 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0230 PM     HAIL             7 SE ENNING             44.51N 102.46W
07/30/2013  M1.00 INCH       MEADE              SD   PUBLIC

&&

KCLARK

Local storm report, Jul 30, 3:13 PM CST, 47 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RAPID CITY SD
313 PM MDT TUE JUL 30 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0309 PM     HAIL             3 NNE CREIGHTON         44.29N 102.18W
07/30/2013  M1.00 INCH       PENNINGTON         SD   TRAINED SPOTTER

&&

KCLARK

Special weather statement, Jul 30, 3:27 PM CST, 33 minutes before

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Local storm report, Jul 30, 3:46 PM CST, 14 minutes before

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Local storm report, Jul 30, 3:50 PM CST, 10 minutes before

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The radar

The North Platte radar (KLNX), 157 km away, was scanning. The volume nearest the first event began at 22:02 UTC.

Open the radar archive at this moment

Event by event

1 flash flood. Local standard time, as filed.

Flash Flood, Todd

When: July 30, 4:00 PM CST to July 31, 1:00 AM CST
Where: Todd County, 6.38 mi ENE of Parmelee to 7.56 mi SSE of Parmelee
Cause: Heavy Rain
Property damage: $60,000
Reported by: Other Federal Agency
Coordinates: 43.350, -100.900

Debris clogged the outlet works at Ghost Hawk Dam and Rosebud Dam, causing the dams to overflow after heavy rain. In addition, a breach of Omaha Boy Dam, about a mile southwest of the Rosebud Dam, increased inflows into the lake. Several culverts and roads were damaged by the flooding, including Ghost Hawk Road and Grass Mountain Road. The Little White River near Rosebud rose from less than 100 cfs to over 1000 cfs in less than four hours, with a peak flow of 1300 cfs.

What these are

Flash Flood: Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in South Dakota in 2013 Every state in 2013 This day in weather history Warnings in South Dakota, July 2013

Sources

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 2026-10-01. Each event’s entry at NCEI: 469293.