Flash Flood, Pennington
- When
- May 24, 5:20 PM MST to 8:30 PM MST
- Where
- Pennington County, 0.56 mi ENE of Rapid City to 2.11 mi SE of Rapid City
- Cause
- Heavy Rain
- Reported by
- Emergency Manager
- Coordinates
- 44.082, -103.209
Flash Flood in South Dakota, May 24, 2009
Two to three inches of rain caused flash flooding along Rapid Creek from Omaha Street and Maple Avenue in Rapid City east to Rapid Valley.
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
The toll
- Deaths
- 0
- Injuries
- 0
- Property damage
- None recorded
- 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.
Two to three inches of rain caused flash flooding along Rapid Creek from Omaha Street and Maple Avenue in Rapid City east to Rapid Valley.
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 May 24, 12:36 PM MST, 4 hours 44 minutes earlier.
Area forecast discussion, May 24, 12:36 PM MST, 4 hours 44 minutes before
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY NATIONAL WEATHER SERVICE RAPID CITY SD 136 PM MDT SUN MAY 24 2009 .DISCUSSION...THE LATEST WATER VAPOR IMAGES SHOWED A BROAD TROUGH OVER THE CNTRL AND NRN ROCKIES WITH SEVERAL EMBEDDED SHORTWAVES... THE MOST NOTABLE OVER WRN-NRN WY. THIS WAVE WAS PRODUCING A BAND OF SHOWERS AND T-STORMS OVER CNTRL WY. ANOTHER WEAKER WAVE WAS MOVING ACROSS WRN SD...AND WAS ASSOCIATED WITH A BAND OF SHOWERS FROM SERN MT THROUGH SCNTRL SD. SOUTHEAST SURFACE FLOW WAS ALLOWING MOIST AIR (DEWPOINTS IN THE 50S) TO SPREAD OVER MOST OF THE CWFA...WITH THE EXCEPTION OF THE FAR ERN AREAS WHERE DEWPOINTS WERE IN THE LOW 40S. A COLD FRONT WAS MOVING SOUTHEAST ACROSS CNTRL MT...ALTHOUGH THE PRESSURE FALLS WERE ONLY 1MB/3HR BEHIND THE FRONT. FOR TONIGHT...THE MIDLEVEL SHORTWAVE TROF OVER WY WILL MOVE THRU THE AREA...WITH THE STRONGEST LIFT OVER THE NORTHERN CWFA AND PLACES TO THE NORTHEAST AS THE LOW-LEVEL JET INCREASES AND FOCUSES ISENTROPIC LIFT IN THAT AREA. WIDESPREAD PRECIP IS EXPECTED WITH SOME LOCALLY HEAVY RAIN AS PW IS 150-200 PERCENT OF AVERAGE. ELEVATED CAPE OF 250-500 J/KG WILL BE SUFFICIENT FOR T-STORMS OVER ALL OF THE AREA. ALTHOUGH DEEP-LAYER SHEAR IS ONLY MARGINALLY FAVORABLE FOR A FEW BRIEFLY ORGANIZED STORMS...LOW-LEVEL SHEAR AND LCL HEIGHTS ARE IN THE FAVORABLE RANGE FOR A BRIEF SPINUP WITH ANY STORM THAT DOES GET ORGANIZED (NERN WY BEARS WATCHING THRU EARLY EVNG). BY 12Z THE MT COLD FRONT SHOULD HAVE REACHED FAR WRN SD...SWITCHING THE WINDS TO THE NORTHWEST. FOR MEMORIAL DAY...WEAK UPPER TROUGH WILL REMAIN OVER AREA ALLOWING FOR RESIDUAL SHOWERS AND T-STORMS. THE BEST CHANCE OF PRECIP WILL BE OVER THE ERN CWFA NEAR THE SURFACE FRONT AND LOW-LEVEL BAROCLINIC ZONE...WHERE MLCAPE WILL BE 500-1000 J/KG. DEEP LAYER SHEAR WILL BE RATHER WEAK SO DO NOT EXPECT ORGANIZED STORMS. ON MONDAY EVENING...FRONT WILL PUSH THROUGH ALL OF CWFA...BUT UPPER TROUGH WILL REMAIN OVER CNTRL SD...KEEPING A CHANCE OF PRECIP IN THAT AREA...WITH ISOLATED ACTIVITY OVER THE REST OF THE CWFA. FLOW FROM THE NORTH WILL GRADUALLY BRING IN DRIER AND COOLER AIR. FOR TUESDAY AND TUESDAY NIGHT...HEIGHTS WILL BE BUILDING AS A SHORTWAVE RIDGE ESTABLISHES ITSELF OVER THE AREA. DRY AIR WILL CONTINUE TO FILTER INTO THE CWFA...AND TEMPERATURE ADVECTION WILL BE WEAK NEGATIVE TO NEUTRAL. RETURN SOUTHERLY FLOW WILL DEVELOP TUESDAY NIGHT OVER NERN WY AND FAR WRN SD...SIGNALING THE BEGINNING OF A WARMING TREND. EXTENDED...MAINLY DRY WX IS ANTICIPATED FOR THE MIDDLE AND LATTER PART OF NEXT WEEK AS UPPER LEVEL RIDGING BUILDS OVER THE NORTHERN ROCKIES. HOWEVER...THERE COULD BE A FEW AFTERNOON AND EVENING THUNDERSTORMS ACROSS WESTERN PORTIONS OF THE AREA...MAINLY NORTHEAST WY AND THE BLACK HILLS...DUE TO HEATING OF THE DAY AND WEAK ENERGY ROTATING AROUND THE RIDGE. TEMPERATURES WILL GENERALLY BE ABOVE AVERAGE...WITH HIGHS IN THE 70S AND 80S. && .AVIATION...RAIN SHOWERS AND MVFR/IFR CONDITIONS WILL CONTINUE ACROSS MUCH OF THE AREA THIS AFTERNOON AND CONTINUE INTO TONIGHT. A FEW THUNDERSTORMS ARE ALSO EXPECTED...ESPECIALLY ACROSS NORTHEAST WY AND SOUTHERN SOUTH DAKOTA...DURING THE LATE AFTERNOON AND EVENING HOURS. MAIN BAND OF HEAVIER SHOWERS AND THUNDERSTORMS SHOULD PUSH EAST BY MIDDAY MONDAY...WITH A RETURN TO MAINLY VFR CONDITIONS BY MONDAY AFTERNOON. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...NONE. WY...NONE. && BUNKERS/RUDGE
Hazardous weather outlook, May 24, 3:21 AM MST, 13 hours 59 minutes before
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE RAPID CITY SD 421 AM MDT SUN MAY 24 2009 SDZ001-002-012>014-024>032-041>044-046-047-049-072>074-WYZ054>058- 071-251300- 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- 421 AM MDT (521 AM CDT) SUN MAY 24 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR WESTERN SOUTH DAKOTA AND NORTHEASTERN WYOMING. .DAY ONE...TODAY AND TONIGHT WIDESPREAD SHOWERS AND THUNDERSTORMS WILL SPREAD NORTH ACROSS THE REGION TODAY AND TONIGHT...AS A STRONG UPPER LEVEL DISTURBANCE MOVES THROUGH THE NORTHERN PLAINS. THE BIGGEST THREAT FROM THUNDERSTORMS WILL BE LOCALLY HEAVY RAINFALL. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY WIDESPREAD SHOWERS AND THUNDERSTORMS WILL CONTINUE ACROSS THE AREA INTO EARLY MONDAY...THEN SLOWLY END FROM WEST TO EAST LATE MONDAY OR MONDAY NIGHT. WHILE WIDESPREAD SEVERE STORMS ARE NOT EXPECTED... LOCALLY HEAVY RAINFALL WILL BE POSSIBLE. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY.
In the hours before
Special weather statement, May 24, 3:24 PM MST, 1 hour 56 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE RAPID CITY SD 424 PM MDT SUN MAY 24 2009 SDZ024-028-029-WYZ056>058-242330- CENTRAL BLACK HILLS-NORTHERN BLACK HILLS-SOUTHERN BLACK HILLS- WESTERN CROOK-WESTON-WYOMING BLACK HILLS- INCLUDING THE CITIES OF...BUCKHORN...CLARETON... DEERFIELD AND DEERFIELD RESERVOIR 424 PM MDT SUN MAY 24 2009 ...STRONG THUNDERSTORM APPROACHING THE AREA... AT 423 PM MDT...DOPPLER RADAR INDICATED A THUNDERSTORM WITH PENNY SIZED HAIL AND FREQUENT CLOUD TO GROUND LIGHTNING. THIS STORM WAS LOCATED NEAR CLARETON...OR 27 MILES WEST OF DOWNTOWN NEWCASTLE...AND WAS MOVING NORTHEAST AT 30 MPH. LOCATIONS IMPACTED INCLUDE... DOWNTOWN NEWCASTLE... OSAGE... UPTON... MOON... INYAN KARA MOUNTAIN AND FOUR CORNERS... THIS INCLUDES INTERSTATE 90 BETWEEN WYOMING MILE MARKERS 159 AND 186... HELGESON
Special weather statement, May 24, 3:26 PM MST, 1 hour 54 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE RAPID CITY SD 426 PM MDT SUN MAY 24 2009 SDZ027>029-041-242330- CENTRAL BLACK HILLS-FALL RIVER-SOUTHERN BLACK HILLS- SOUTHERN FOOT HILLS- INCLUDING THE CITIES OF...ARGYLE...BLUE BELL... CENTER LAKE AND CRAZY HORSE MEMORIAL 426 PM MDT SUN MAY 24 2009 ...STRONG THUNDERSTORM APPROACHING THE AREA... AT 425 PM MDT...DOPPLER RADAR INDICATED A THUNDERSTORM WITH PENNY SIZED HAIL AND FREQUENT CLOUD TO GROUND LIGHTNING. THIS STORM WAS LOCATED NEAR EDGEMONT...AND WAS MOVING NORTH AT 30 MPH. LOCATIONS IMPACTED INCLUDE... ARGYLE... PRINGLE... SANATOR AND JEWEL CAVE... BLUE BELL... CRAZY HORSE MEMORIAL...DOWNTOWN CUSTER...SYLVAN LAKE AND STOCKADE LAKE... HELGESON
Special weather statement, May 24, 4:28 PM MST, 52 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE RAPID CITY SD 528 PM MDT SUN MAY 24 2009 SDZ001-002-012>014-024>031-041-042-072>074-WYZ054-056>058-071-250100- BUTTE-CENTRAL BLACK HILLS-CUSTER CO PLAINS-FALL RIVER-HARDING- HERMOSA FOOT HILLS-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 FOOT HILLS-SOUTHERN MEADE CO PLAINS- STURGIS/PIEDMONT FOOT HILLS-WESTERN CROOK-WESTON-WYOMING BLACK HILLS- ZIEBACH- INCLUDING THE CITIES OF...ALADDIN...ALVA... ANGOSTURA RESERVOIR AND ARDMORE 528 PM MDT SUN MAY 24 2009 ...STRONG THUNDERSTORMS APPROACHING THE AREA... AT 526 PM MDT...DOPPLER RADAR INDICATED A LINE OF THUNDERSTORMS WITH HEAVY RAIN...SMALL HAIL...AND FREQUENT CLOUD TO GROUND LIGHTNING. SOME AREAS MAY RECEIVE AS MUCH AS 1 INCH OF RAIN IN A COUPLE OF HOURS. THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM 5 MILES SOUTHEAST OF HULETT TO 5 MILES EAST OF RED SHIRT...AND WERE MOVING NORTHEAST AT 35 MPH. LOCATIONS IMPACTED INCLUDE... FOLSOM...TERRY PEAK...BROWNSVILLE AND NEMO... DOWNTOWN RAPID CITY...CENTRAL CITY...LEAD AND BEULAH... RAPID VALLEY AND RAPID CITY AIRPORT... THIS INCLUDES INTERSTATE 90 BETWEEN SOUTH DAKOTA MILE MARKERS 1 AND 100... THIS INCLUDES INTERSTATE 90 BETWEEN WYOMING MILE MARKERS 148 AND 207... HELGESON
The radar
The Rapid City radar (KUDX), 31 km away, was scanning. The volume nearest the first event began at 00:19 UTC.
Event by event
1 flash flood. Local standard time, as filed.
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
- Flash Flooding in Arkansas, May 24, 2009
- Damaging Wind in Florida, May 24, 2009
- Flooding and Hail in Massachusetts, May 24, 2009
- Hail and Damaging Wind in Florida, May 24 to 25, 2009
- Hail and Damaging Winds in Texas, May 24, 2009
- Tornado and Flash Flooding in Tennessee, May 24, 2009
- Hail and Damaging Winds in Connecticut, May 24, 2009
- Tornado in Texas, May 24, 2009
- Hail and Damaging Winds in Connecticut, May 24, 2009
- Tornado and Hail in Maine, May 24, 2009
- Damaging Winds and Lightning Strike in New Jersey, May 24, 2009
- Marine Thunderstorm Wind in Gulf of Mexico, May 24, 2009
More
Every storm in South Dakota in 2009Every state in 2009This day in weather historyWarnings in South Dakota, May 2009
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 2026-09-24. Each event’s entry at NCEI: 176267.