Thunderstorms produced a tornado, damaging winds, and flash flooding in southeast South Dakota, mostly near Interstate 90, during the evening of August 3rd.
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 FSD wrote it up.
Thunderstorms produced a tornado, damaging winds, and flash flooding in southeast South Dakota, mostly near Interstate 90, during the evening of August 3rd.
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 Sioux Falls, SD wrote its last area forecast discussion before the first event at Aug 3, 5:44 PM CST, 13 minutes earlier.
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA NATIONAL WEATHER SERVICE SIOUX FALLS SD 644 PM CDT TUE AUG 3 2010 .DISCUSSION... QUICK UPDATE TO COVER THE ISOLD STORMS DEVELOPING ALG WK SWRD MOVING OUTFLOW BNDRY INTO AIRMASS OVR SERN SD THAT IS LOCAL MAXIMUM IN POTENTIAL INSTABILITY. OTHER UPDATE NEEDED TO ENHANCE THE THUNDERSTORM THREAT THRU SWRN CWA...MAINLY FOR AREAS ALG/W OF THE JAMES VALLEY WITH SELF SUSTAINING MCS WHICH WL AFFECT WRN CWA MAINLY AFT ABOUT 01Z. CONTINUED DAMAGING WIND THREAT SEEMS IN ORDER GIVEN THE INSTABILITY AND SHEAR PARAMETERS. SHEAR PARAMETERS DECREASE CONSIDERABLY HEADING EWRD THRU THE EVNG...AND EXPECT THAT CURRENT ACTIVITY WK BEGIN TO WKN BY MID EVENING PUSHING TOWARD JAMES VLY... WITH GREATEST INTENSITY SHIFTING SWRD INTO NEBRASKA. ISOLD ERN SD STORMS SO FAR VERY SLOW MOVING...AND ACTUALLY A NET WWRD PROPAGATION TO MANY IN OUR CWA. ENVIRONMENT IS ACTUALLY FAVORABLE FOR A FEW FUNNELS TO DEVELOP IN THIS LINE...GIVEN 0-3KM CAPE AND CONVERGENCE AXIS. && .AVIATION... OVERALL VFR CONDITIONS EXPECTED THROUGH TONIGHT...THOUGH SCATTERED SHOWERS AND THUNDERSTORMS MAY BRIEFLY DROP VISBYS/CIGS INTO THE MVFR/IFR RANGE. BEST CHANCE OF THUNDERSTORM ACTIVITY WILL OCCUR THROUGH THE JAMES RIVER VALLEY BEFORE 06Z...THEN AREAS TO THE EAST BETWEEN 06Z AND 12Z. WINDS WILL BE LIGHT ONCE AGAIN TONIGHT...BUT WITH MORE CLOUD COVER EXPECTING LESS FOG FORMATION. /JM && .PREV DISCUSSION... PRESENT RADAR IMAGE SHOWING LIGHT SHOWERS OVER AREAS ALONG THE MISSOURI RIVER AS ANOTHER IN A SERIES OF SHORTWAVES TRACKS ACROSS THE REGION...INTERACTING WITH LOWER TO MID LEVEL BOUNDARY JUST TO THE SOUTH OF OUR CWA. BACK TO THE WEST...ANOTHER MORE SIGNIFICANT AREA OF THUNDERSTORMS PUSHING INTO WESTERN SOUTH DAKOTA AS ANOTHER SHORTWAVE TRACKS OUT OF THE ROCKIES. QUESTION TONIGHT BECOMES WHETHER THAT CONVECTION CAN MAKE IT INTO OUR WESTERN CWA AS THE WAVE MOVES TO THE EAST. MODELS DIFFERING ON SOLUTIONS...BUT OVERALL TREND IS FOR THESE THUNDERSTORMS TO MOVE EAST THROUGH THE EVENING...THOUGH WEAKENING AS THE ATMOSPHERE BECOMES MORE STABLE WITH LOSS OF HEATING OF THE DAY...AND UPPER LEVEL DIVERGENCE IS LOST AS JET MAX OVER NORTH DAKOTA EXITS TO THE EAST. AT THE SAME TIME...ANOTHER WAVE IS EXPECTED TO PUSH OUT OF NEBRASKA TONIGHT...SO CANNOT RULE OUT SCATTERED SHOWERS/THUNDERSTORMS WITH BOUNDARY SO CLOSE BY...THOUGH NO LOW LEVEL JET DYNAMICS WILL COME INTO PLAY WITH LOW LEVEL WINDS LIGHT...SO KEPT IN THE SMALL CHANCE RANGE. WHILE WINDS WILL BE VERY LIGHT TONIGHT...NOT WORRIED AS MUCH ABOUT FOG WITH MORE CLOUD COVER EXPECTED THAN PREVIOUS NIGHTS. LOWS WILL DROP DOWN INTO THE LOWER TO MID 60S. /JM ON WED...S/W WL BE MOVG THRU ERN CWA AND QUESTION IS HOW FAR THEY CAN GO BEFORE DISSIPATING WITH LOW LEVEL NELY FLOW LATER TONIGHT BRINGING DRIER AIR INTO THE LOW LEVELS E OF I29. STORMS MAY HAVE A HARD TIME MOVG ACRS SW MN ON WED SO WL ONLY GO SLIGHT CHC THERE WITH 30% POPS ALONG THE I29 CORRIDOR INTO NW IA. WL KEEP SMALL POPS ACRS CWA DURING THE AFTN WITH WEAK SECONDARY FNT WITH CAPES OF 1000 TO 2000 IN THE AFTN. PBLY WL ONLY BE ISOLD AT BEST AS NO S/W REALLY TO TRIGGER ANYTHING MORE. ANY ACTIVITY THAN DOES DEVELOP IN THE AFTN SHUD FALL APART QUICKLY IN THE EVE. WED NITE AND THU SHUD BE A QUIET PD WITH NEAR NORM TEMPS BUT NOT AS HUMID. RETURN FLOW AND WAA WILL PUSH WRMFNT N THRU CWA LATE THU NITE INTO FRI MORN. CUD SEE A FEW HIGH BAST TRW DEVELOPING MAINLY ALONG AND N OF I90 LATE THU NITE INTO FRI MORN SO WL INTRODUCE A SMALL POP ACRS NRN CWA. ANOTHER S/W MOVES EWD ACRS THE NRN PLAINS SAT AND SAT NITE. THIS TIME AROUND IT APPEARS THAT MOST OF THE ENERGY WL GO N OF CWA AS EC AND GFS DOES SHOW A PRETTY STOUT CAP DEVELOPING AS RIDGE ALOFT BUILDS ON SAT. SO WL NOT GO TOO WILD WITH POPS AND KEEP THEM IN THE 20 TO 30% RANGE FOR SAT AND SAT NIGHT. SUN SHUD BE WARM AND HUMID WITH CWA CAPPED OFF. NEXT S/W WL BRING A CHC OF STORMS MON AND MON NITE AS WEAK CDFNT PUSHES EWD THRU CWA. OTHER THAN A BRIEF RESPITE FM THE HUMIDITY ON THU...SHUD BE WARM AND HUMID FOR THE NEXT 7 DAYS. && .FSD WATCHES/WARNINGS/ADVISORIES... IA...NONE. MN...NONE. NE...NONE. SD...NONE. &&
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE SIOUX FALLS SD 1054 AM CDT TUE AUG 03 2010 SDZ038>040-050-052>071-MNZ071-072-080-081-089-090-097-098- IAZ001>003-012>014-020>022-031-032-NEZ013-014-041200- AURORA-BEADLE-BON HOMME-BROOKINGS-BRULE-BUENA VISTA IA- CHARLES MIX-CHEROKEE IA-CLAY-CLAY IA-COTTONWOOD MN-DAKOTA NE- DAVISON-DICKINSON IA-DIXON NE-DOUGLAS-GREGORY-HANSON-HUTCHINSON- IDA IA-JACKSON MN-JERAULD-KINGSBURY-LAKE-LINCOLN-LINCOLN MN- LYON IA-LYON MN-MCCOOK-MINER-MINNEHAHA-MOODY-MURRAY MN-NOBLES MN- OBRIEN IA-OSCEOLA IA-PIPESTONE MN-PLYMOUTH IA-ROCK MN-SANBORN- SIOUX IA-TURNER-UNION-WOODBURY IA-YANKTON- 1054 AM CDT TUE AUG 03 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST SOUTH DAKOTA... SOUTHWEST MINNESOTA...NORTHWEST IOWA...AND NORTHEAST NEBRASKA. .DAY ONE...TODAY AND TONIGHT THUNDERSTORMS... ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP FROM THE WEST LATE THIS AFTERNOON AND TONIGHT. SEVERE STORMS ARE NOT EXPECTED AT THIS TIME...ALTHOUGH ISOLATED STORMS COULD PRODUCE SMALL HAIL. FLOODING... RIVER FLOODING WILL CONTINUE ALONG THE JAMES RIVER FOR AN EXTENDED PERIOD. RIVER FLOODING IS ALSO OCCURRING OVER PORTIONS OF THE VERMILION RIVER...BIG SIOUX RIVER...AND FIRESTEEL CREEK...BUT WITHOUT ADDITIONAL RAINFALL...THESE RIVERS WILL DROP BELOW FLOOD STAGE OVER THE NEXT FEW DAYS. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY ISOLATED TO SCATTERED THUNDERSTORMS ARE POSSIBLE WEDNESDAY. THE THUNDERSTORMS SHOULD END FROM THE NORTH WEDNESDAY NIGHT. SEVERE STORMS ARE NOT EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY AND TONIGHT. && FOR MORE INFORMATION PLEASE VISIT OUR WEBSITE AT WWW.WEATHER.GOV/SIOUXFALLS. THIS INCLUDES THE GRAPHICAL HAZARDOUS WEATHER OUTLOOK.
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SIOUX FALLS SD 647 PM CDT TUE AUG 3 2010 SDZ053>056-059>062-040200- SANBORN-MINER-LAKE-MOODY-DAVISON-HANSON-MCCOOK-MINNEHAHA- INCLUDING THE CITIES OF...WOONSOCKET...HOWARD...MADISON... FLANDREAU...MITCHELL...ALEXANDRIA...EMERY...SALEM...CANISTOTA... BRIDGEWATER...MONTROSE...SIOUX FALLS 647 PM CDT TUE AUG 3 2010 ...SPECIAL WEATHER STATEMENT... ISOLATED FUNNEL CLOUDS WILL BE POSSIBLE ALONG A LINE OF SHOWERS AND THUNDERSTORMS JUST NORTH OF INTERSTATE 90. THE FUNNEL CLOUDS ARE EXPECTED TO BE BRIEF AND SHOULD NOT BECOME TORNADOES.
The Sioux Falls radar (KFSD), 92 km away, was scanning. The volume nearest the first event began at 23:58 UTC.
4 thunderstorm wind, 2 tornado, 2 flash flood, 1 heavy rain. Local standard time, as filed.
A brief tornado near the county line raised dust, but caused no reported damage. The tornado crossed briefly into Miner County before dissipating.
A brief tornado caused no reported damage. The tornado crossed into Miner County from Hanson County before quickly dissipating.
Thunderstorm winds caused tree damage.
Thunderstorm winds caused tree damage, including branches blown down.
Heavy rain from thunderstorms caused flash flooding of several streets in the town of Wessington Springs.
Thunderstorm winds caused tree damage, including several branches blown down.
Thunderstorm winds caused minor tree damage.
Heavy rain from thunderstorms produced flash flooding of several streets in Sioux Falls, with several vehicles stalled.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in South Dakota in 2010Every state in 2010This day in weather historyThe tornado archive for South Dakota, 2010Warnings in South Dakota, August 2010
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: 255983, 255984, 255985, 255986, 255988, 255990, 255991, 255993, 255994.