A short wave trough, warm air advection, low level convergence, and high moisture profiles resulted in very heavy rains and flash flooding across parts of central South Dakota.
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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 ABR wrote it up.
A short wave trough, warm air advection, low level convergence, and high moisture profiles resulted in very heavy rains and flash flooding across parts of central South Dakota.
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 Aberdeen, SD wrote its last area forecast discussion before the first event at Aug 3, 2:02 PM CST, 7 hours 58 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ABERDEEN SD 302 PM CDT FRI AUG 3 2007 .SHORT TERM...TONIGHT THROUGH SATURDAY THE MAIN CONCERN DURING THIS TIME PERIOD WILL BE PCPN AND HOW MUCH. STILL LOOKS LIKE THINGS ARE ON TRACK FOR DECENT PCPN EVENT ACROSS MOST OF THE CWA AS ENERGY ALOFT ROLLS ACROSS PLAINS WITH INDUCED SFC LOW TRACKING ACROSS SOUTHERN SOUTH DAKOTA. ONLY BIG PROBLEM REALLY IS TRYING FIGURE OUT EXACTLY WHERE THE HEAVIEST PCPN BAND WILL BE. 12Z NAM STUCK TO ITS GUNS WITH HEAVY RAIN ACROSS NORTHERN CWA...GFS ON THE OTHER HAND REMAINS FURTHER SOUTH. TRACK OF UPPER LEVEL FEATURES SUGGESTS NAM IS THE BEST SOLUTION. HOWEVER...CORFIDI VECTORS SAY THAT ANY MCS THAT DEVELOPS OVER WESTERN DAKOTAS MAY WELL SWERVE EAST/SOUTHEAST TOWARD SOUTHERN PART OF STATE. THIS IS WHERE HPC SEEMS TO BE LEANING WITH THEIR PROGS...AND I HAVE NO REAL PROBLEMS WITH THAT. THUS HAVE BACK OFF CONSIDERABLY ON EXPECTED QPF ACROSS NORTHERN CWA. SVR THREAT ALSO APPEARS TO BE GREATEST OVER WESTERN CWA WHERE SOME DIABATIC HEATING HAS CREATED MODERATE AMOUNTS OF SURFACE BASED INSTABILITY THIS AFTERNOON. THE EASTERN CWA HAS SEEN LESS DIABATIC HEATING TODAY...THAT ALONG WITH SOMEWHAT UNFAVORABLE H7 TO H5 LAPSE RATES AND AND MINIMAL AMOUNTS OF AVAILABLE CONVECTIVE ENERGY SUGGESTS THE THREAT OF SEVERE IS RATHER LOW. TEMPERATURES WERE MOSTLY BASED ON ADJMAV WITH SOME MODIFICATIONS WHERE APPROPRIATE. .MID TERM...SATURDAY NIGHT THROUGH SUNDAY NIGHT THE FORECAST AREA APPEARS TO BE BETWEEN SYSTEMS SATURDAY NIGHT INTO THE FIRST HALF OF SUNDAY. BOTH THE GFS AND NAM INDICATE A COLD FRONTAL PASSAGE FROM ASSOCIATED UPPER WAVE MOVING ESEWD ALOFT ALONG THE INTERNATIONAL BORDER OF THE NORTHERN PLAINS AND CANADA. BY SUNDAY NIGHT THE BOUNDARY APPEARS TO BE SAGGING SOUTHWARD INTO THE FORECAST AREA WITH PLENTY OF LOW LEVEL MOISTURE ADVECTING NORTHWARD TO MEET IT. ALL THIS WHILE ANOTHER ALBEIT WEAKER UPPER WAVE IS LIFTING OUT ONTO THE NORTHERN HIGH PLAINS SUNDAY AND EVENTUALLY THIS FORECAST AREA SUNDAY NIGHT. WITH MODELS INDICATING MODEST INSTABILITY ALONG THIS COLD FRONT AS IT SLIPS SOUTHWARD ACROSS THE FORECAST AREA...ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP ALONG THE FRONTAL BOUNDARY AS THIS UPPER WAVE MOVES ACROSS THE REGION. TEMPERATURES SATURDAY NIGHT WILL BE NEAR TO SLIGHTLY BELOW NORMAL WITH WEAK SURFACE HIGH PRESSURE BUILDING INTO THE REGION AND PLENTY OF STABLE...RAIN- COOLED AIR IN PLACE BEHIND THE LOW PRESSURE SYSTEM THAT...BY SATURDAY NIGHT...HAS PUSHED OFF INTO THE MID-MISSISSIPPI RIVER VALLEY. .LONG TERM...MONDAY THROUGH FRIDAY NIGHT THE EXTENDED PERIOD BEGINS IN THE UPPER LEVELS WITH WESTERLY FLOW ACROSS THE NORTHERN PLAINS AND A 135KT JET MAXIMUM OVER NORTH DAKOTA. UPPER LEVEL RIDGING SEEN OVER THE LAST FEW DAYS BEGINS TO BREAK DOWN DURING THE FIRST HALF OF THE EXTENDED PERIOD WITH THE DEPARTURE OF THE UPPER LEVEL HIGH TO THE EAST AND THE APPROACH OF AN UPPER LOW ORIGINATING FROM THE PACIFIC NW. THIS SETS THE STAGE FOR MORE ACTIVE WEATHER WITH THE PASSAGE OF SEVERAL SHORTWAVES THROUGH THE FLOW PATTERN. THE MAIN FORECAST CHALLENGE THROUGH THE EXTENDED PERIOD REMAINS PINPOINTING AREAS OF PRECIPITATION. THE BEST CHANCE IS MONDAY EVENING THROUGH THE OVERNIGHT HOURS AS A SURFACE LOW IS PROGGED TO TRACK ACROSS SOUTHERN SOUTH DAKOTA. BOTH THE 06Z AND 12Z GFS SHOWED DECENT WARM AIR ADVECTION OVERNIGHT COUPLED WITH A WEAK LOW LEVEL JET TO SUPPORT OVERNIGHT CONVECTION. IN ADDITION...THE MODELS SHOWED SOME MID LEVEL FORCING THROUGH MOST OF THE NIGHT WITH RATHER DECENT 700MB THETA E ADVECTION AND MID LEVEL LIFT. WENT WITH 20S AND 30S POPS ACROSS MOST OF CWA FOR NOW. OTHER FOCUS TIMES ARE WEDNESDAY EVENING INTO THE NIGHT AND FRIDAY EVENING INTO THE NIGHT. WENT WITH SLIGHTLY LOWER POPS FOR NOW...AS THE MODELS ARE NOT YET TERRIBLY CONSISTENT WITH PLACEMENT DURING THESE TIME PERIODS. && .AVIATION... FOR THE MOST PART...VFR CONDITIONS ARE EXPECTED OVER CENTRAL/NORTHEAST SOUTH DAKOTA INTO THE EVENING. HOWEVER...CIGS AND VSBYS WITH SCT THUNDERSTORMS COULD FALL INTO THE IFR/MVFR RANGE FOR SHORT PERIODS OF TIME. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && SHORT TERM...TDK LONG TERM...GIONTA AVIATION...TDK
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE ABERDEEN SD 507 AM CDT FRI AUG 3 2007 SDZ003-004-009-015-016-033>035-045-048-041015- CORSON-CAMPBELL-WALWORTH-DEWEY-POTTER-STANLEY-SULLY-HUGHES-JONES- LYMAN- 507 AM CDT FRI AUG 3 2007 /407 AM MDT FRI AUG 3 2007/ THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL SOUTH DAKOTA AND NORTH CENTRAL SOUTH DAKOTA. .DAY ONE...TODAY AND TONIGHT AN AREA OF LOW PRESSURE WILL MOVE INTO THE UPPER PLAINS LATER THIS AFTERNOON. SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP WITH THIS FEATURE. SOME OF THE STORMS COULD BECOME STRONG TO SEVERE. LARGE HAIL...DAMAGING WIND GUSTS AND LOCALLY HEAVY RAIN IS POSSIBLE. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY THERE IS A SLIGHT CHANCE OF FURTHER THUNDERSTORM DEVELOPMENT SUNDAY THROUGH MONDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED AFTER 2PM CDT THIS AFTERNOON. SDZ005-006-010-017-018-036-037-051-041015- MCPHERSON-BROWN-EDMUNDS-FAULK-SPINK-HYDE-HAND-BUFFALO- 507 AM CDT FRI AUG 3 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL SOUTH DAKOTA...NORTH CENTRAL SOUTH DAKOTA AND NORTHEAST SOUTH DAKOTA. .DAY ONE...TODAY AND TONIGHT LOW PRESSURE WILL EJECT INTO THE UPPER MIDWEST LATER TODAY. THIS LOW WILL ENTERACT WITH THE INCREASINGLY MORE HUMID AND UNSTABLE AIR MOVING TO THE NORTH. THIS WILL RESULT IN WIDESPREAD SHOWERS AND THUNDERSTORMS LATE THIS AFTERNOON INTO THE EVENING. LARGE HAIL AND DAMAGING WINDS ARE THE MAIN THREAT. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY ISOLATED SHOWERS AND THUNDERSTORMS ARE AGAIN POSSIBLE LATE SUNDAY AFTERNOON. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED AFTER 5PM CDT THIS AFTERNOON. MNZ039-046-SDZ007-008-011-019>023-041015- TRAVERSE-BIG STONE-MARSHALL-ROBERTS-DAY-CLARK-CODINGTON-GRANT- HAMLIN-DEUEL- 507 AM CDT FRI AUG 3 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF WEST CENTRAL MINNESOTA AND NORTHEAST SOUTH DAKOTA. .DAY ONE...TODAY AND TONIGHT SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS EVENING IN RESPONSE TO AN ARA OF LOW PRESSURE MOVING INTO THE PLAINS. DAMAGING WINDS...LARGE HAIL AND BRIEF HEAVY RAIN ARE ALL POSSIBLE WITH THE STORMS. .DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY ISOLATED SHOWERS AND THUNDERSTORMS ARE AGAIN POSSIBLE LATE SUNDAY AFTERNOON. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED AFTER 8PM CDT.
The Aberdeen radar (KABR), 131 km away, was scanning. The volume nearest the first event began at 04:02 UTC.
3 flash flood. Local standard time, as filed.
Heavy rains of 4 to 6 inches caused flash flooding of roads in and around Highmore. Some homes also received water in their basements.
Heavy rains of 5 to 7 inches caused flash flooding of streets and roads in and around Miller for several hours. A few homes received some water in them, some sewers backed up, and several roads were closed.
A county road was underwater three miles south of Onida for several hours.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in South Dakota in 2007Every state in 2007This day in weather historyWarnings in South Dakota, August 2007
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: 57372, 57393, 57381.