Thunderstorms produced damaging winds and large hail in Brule, Douglas, and Gregory Counties of southeast South Dakota 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 damaging winds and large hail in Brule, Douglas, and Gregory Counties of southeast South Dakota 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, 7:25 PM CST, 36 minutes earlier.
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA NATIONAL WEATHER SERVICE SIOUX FALLS SD 825 PM CDT MON AUG 3 2009 .DISCUSSION... CONVECTION BEHAVING ABOUT AS EXPECTED WITH THUNDERSTORMS EAST OF ABERDEEN INTO MINNESOTA HAVING A HARD TIME MAINTAINING UPDRAFT STRENGTH WHILE THUNDERSTORMS IN CENTRAL SD HAVE ACCESS TO BETTER INSTABILITY AND MODERATE SHEAR. EXPECT THE CENTRAL SD THUNDERSTORMS TO CONTINUE FOR AT LEAST THE NEXT FEW HOURS...POSSIBLY TURNING A LITTLE MORE EASTWARD AND HEADING TOWARDS YANKTON. AT THIS TIME IT LOOKS LIKE SEVERE WEATHER THREAT WILL BE ISOLATED THIS EVENING AND AFTER SUNSET WITH QUARTER SIZED HAIL AND WIND GUSTS TO 70 MPH THE MAIN THREATS. OTHERWISE...MADE SOME MINOR TWEAKS TO THE DEW POINT AND TEMPERATURE GRIDS THIS EVENING TO COMPENSATE FOR HIGHER DEW POINTS AND FALLING TEMPERATURES WITHIN CONVECTION IN SC SD. ALSO INCREASED POPS WEST OF THE JAMES FOR THE EVENING HOURS. /08 && .AVIATION... GENLY VFR THRU PD. SPOTTY TRW W OF JAMES RVR AND MOVE SEWD OVERNIGHT INTO TUES MORN. CIGS AND VSBYS OCNLY MVFR IN TRW. && .PREV DISCUSSION... S/W DROPPING SEWD INTO NW SD ATTM AND SHUD PUSH SEWD ACRS CWA AS SFC BNDRY SAGS SWWD INTO SRN CWA. LLM WL LIKELY POOL NEAR THIS BNDRY ACRS SRN CWA THRU THE NIGHT. NOT SURE IF ANY CONVECTION WL GO THIS EVE ALONG FNT ESPEC NRN CWA AS BETTER INSTABIL SETS UP LATER TONIGHT S OF I90 ACRS SCNTRL SD INTO NW IA. SO FOR NOW WL KEEP ONLY 20% ACRS THE N WITH CHC POPS S OF I90 AND W OF I29 TONIGHT. SHUD SEE A FEW TRW FIRE UP THIS EVE ACRS FAR WRN CWA AND THEN SPREAD SLOWLY EWD ALONG AXIS OF INSTABIL AND H85 FNT LATER TONIGHT. WL KEEP THREAT OF PRECIP OUT OF MOST OF NW IA FOR TONIGHT...XCP NR SUX LATER TONIGHT. IF CONVECTION CAN GET GOING ALONG MO RVR...IT SHUD TRACK ESEWD TOWARDS SUX BY MORN. WEATHER PATTERN WILL BEGIN TO CHANGE DURING THE WEEK AS UPPER LOW OFF THE CA COAST WORKS INLAND. WILL ACTUALLY SEE MORE TYPICAL SUMMER LIKE WEATHER RETURN TO THE REGION THIS WEEKEND...AND LIKELY MUCH OF NEXT WEEK. IN THE MEAN TIME...COOLER AIR WILL REMAIN IN PLACE ALONG WITH ON AND OFF CHANCES FOR THUNDERSTORMS. MAIN CHANCES WILL BE ALONG THE MID LEVEL INSTABILITY AXIS WHICH WILL GENERALLY REMAIN ALONG AND WEST OF THE JAMES VALLEY...EXTENDIN THROUGH THE MISSIOURI VALLEY MUCH OF THE WEEK. THUNDERSTORM ACTIVITY TO LARGELY BE DRIVEN DIURNALLY...WITH CONVECTION DEVELOPING IN THE ROCKIES AND MOVING INTO THE PLAINS DURING THE OVERNIGHT...RIDING THE AXIS OF INSTABILITY. STILL...TIMING OF THUNDERSTORM ACTIVITY A BIT TRICKY MUCH OF THE WEEK AS ANY SUBTLE IMPULSE COULD POP CONVECTION. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE.
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE SIOUX FALLS SD 1021 AM CDT MON AUG 03 2009 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- 1021 AM CDT MON AUG 03 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHEAST SOUTH DAKOTA... SOUTHWEST MINNESOTA...NORTHWEST IOWA...AND NORTHEAST NEBRASKA. .DAY ONE...TODAY AND TONIGHT THUNDERSTORMS... WIDELY SCATTERED THUNDERSTORMS SHOULD DEVELOP AHEAD OF A WEAK COLD FRONT MOVING SOUTHEAST OVER THE AREA TONIGHT. ISOLATED STORMS COULD PRODUCE HAIL UP TO NICKEL SIZE AND WIND GUSTS TO 60 MPH NEAR AND WEST OF THE JAMES RIVER VALLEY THIS EVENING. HOWEVER...WIDESPREAD SEVERE WEATHER IS NOT EXPECTED. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY THERE IS A CHANCE OF THUNDERSTORMS MOVING EAST OVER THE AREA FROM LATER TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. THE BEST CHANCE OF ANY SEVERE STORMS SHOULD BE NEAR THE MISSOURI VALLEY FROM CHAMBERLAIN TO YANKTON. THUNDERSTORMS WILL BE POSSIBLE AT ANY TIME FROM THURSDAY INTO THE WEEKEND. THE BEST CHANCE APPEARS TO BE THURSDAY AFTERNOON THROUGH FRIDAY. SEVERE STORMS AND HEAVY RAINS WILL BE POSSIBLE. .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.
The Sioux Falls radar (KFSD), 180 km away, was scanning. The volume nearest the first event began at 02:01 UTC.
6 thunderstorm wind, 6 hail. Local standard time, as filed.
Thunderstorm winds cause tree damage, and moved large, heavy construction barrels.
Thunderstorm winds blew over numerous heavy road construction signs.
Thunderstorm winds caused tree damage, including several branches blown down.
Large hail, up to two inches in diameter, fell in a swath a few miles wide from northwestern to south central Gregory County. The hail broke numerous windows, severely damaged siding and roofs of homes and other buildings, and severely damaged vehicles, while covering the ground in several places. Property damage was especially severe in the town of Gregory. Crop damage was also severe along the swath, with corn crops in some areas destroyed to the point of only small stubble left.
Large hail was accompanied by wind gusts up to 50 mph. The hail damaged vehicles, cracked windows, and damaged roofs and siding on buildings. The hail also caused crop damage in the area. The amount of local property and crop damage was not known, with the hail causing severe damage in a long swath over part of the county.
Large hail broke windows and severely damaged roofs, siding, and vehicles. The hail also stripped leaves from trees, and caused crop damage in the area. The amount of local property and crop damage was not known; the hail being part of a long swath of large hail that affected part of the county. The hail was accompanied by wind gusts up to 50 mph.
Large hail caused damage to vehicles, siding, roofs, and crops. The amount of local; damage was not known; the hail being part of a long swath that affected part of the county. The hail was accompanied by wind gusts up to 60 mph.
Thunderstorm winds caused tree damage, including several branches blown down. The winds were accompanied by large hail, and added to crop damage caused by the hail.
Large hail damaged vehicles and broke windows, and damaged area crops. The amount of local property and crop damage was not known; the hail being part of a long swath that affected part of the county. The hail was accompanied by wind gusts up to 60 mph.
Large hail caused tree damage, including 30 year old trees blown down. The winds were accompanied by large hail, and added to crop damage in the area caused by the hail.
Large hail broke windows, damaged vehicles, roofs, and siding, and caused crop damage, especially to corn crops. The amount of property and crop damage was not known.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in South Dakota in 2009Every state in 2009This day in weather historyWarnings in South Dakota, August 2009
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: 191625, 191626, 191628, 191629, 191978, 191979, 191980, 191981, 191982, 191983, 191984, 191985.