Thunderstorm Wind, Stanley
- When
- July 21, 12:10 AM CST
- Where
- Stanley County, 5 mi W of Ft Pierre
- Measured
- 52 kt (60 mph)
- Reported by
- GENERAL PUBLIC
- Coordinates
- 44.350, -100.467
Sixty mph winds brought many tree branches down.
Damaging Winds in South Dakota, July 21, 2002
11 thunderstorm wind, as filed by the National Weather Service.
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
- 11
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 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 Aberdeen, SD wrote its last area forecast discussion before the first event at Jul 20, 8:35 PM CST, 3 hours 35 minutes earlier.
Area forecast discussion, Jul 20, 8:35 PM CST, 3 hours 35 minutes before
AREA FORECAST DISCUSSION FOR CENTRAL/N-EAST SD AND W-CENTRAL MN NATIONAL WEATHER SERVICE ABERDEEN SD 935 PM CDT SAT JUL 20 2002 CONVECTION IN W SD LATE THIS EVENING WAS INCREASING IN COVERAGE AS SHOWN BY RADARS...COOLING AND EXPANDING TOPS ON SATELLITE AND INCREASING LIGHTNING ACTIVITY. AS THE LLJ INCREASES FROM THE S THROUGH THE NIGHT AND INTERSECTS THE BOUNDARY ACROSS S SD WHILE THE CAP TO THE NORTH OF THE BOUNDARY WEAKENS...THIS CONVECTION SHOULD CONTINUE TO EXPAND NORTHEAST ACROSS MUCH OF THE ABR CWA THROUGH THE NIGHT AND EXIT NE SD AND WC MN SUN MRNG. THEREFORE...HAVE INCREASED POPS FOR TONIGHT ACROSS THE AREA AND CONTINUED THEM IN THE NE PART OF THE CWA ON SUN MRNG. TEMPS WILL FALL INTO THE UPPER 60S TO THE LOWER 70S BY MRNG WITH N TO NE WINDS AT 5 TO 15 MPH CONTINUING N OF THE BOUNDARY. UPDATED FORECAST AND MADE CHANGES. .ABR...NONE MOHR
The radar
The national radar mosaic for the moment the first event began.
Event by event
11 thunderstorm wind. Local standard time, as filed.
Thunderstorm Wind, Hughes
- When
- July 21, 12:25 AM CST
- Where
- Hughes County, Pierre
- Measured
- 51 kt (59 mph)
- Reported by
- AWOS,ASOS,MESONET,ETC
- Coordinates
- 44.367, -100.333
Thunderstorm Wind, Edmunds
- When
- July 21, 2:40 AM CST
- Where
- Edmunds County, Mina
- Measured
- 52 kt (60 mph)
- Reported by
- GENERAL PUBLIC
- Coordinates
- 45.433, -98.767
Many tree branches were brought down near Mina.
Thunderstorm Wind, Spink
- When
- July 21, 2:45 AM CST
- Where
- Spink County, Mellette
- Measured
- 65 kt (75 mph)
- Reported by
- AWOS,ASOS,MESONET,ETC
- Coordinates
- 45.150, -98.500
Some tree branches were brought down by winds over 70 mph.
Thunderstorm Wind, Clark
- When
- July 21, 3:00 AM CST
- Where
- Clark County, 7 mi SE of Bradley
- Measured
- 52 kt (60 mph)
- Reported by
- GENERAL PUBLIC
- Coordinates
- 45.017, -97.533
Thunderstorm Wind, Codington
- When
- July 21, 3:00 AM CST
- Where
- Codington County, Florence
- Measured
- 56 kt (64 mph)
- Reported by
- TRAINED SPOTTER
- Coordinates
- 45.050, -97.317
Thunderstorm Wind, Brown
- When
- July 21, 3:00 AM CST
- Where
- Brown County, Groton
- Measured
- 70 kt (81 mph)
- Reported by
- TRAINED SPOTTER
- Coordinates
- 45.450, -98.100
Winds to 80 mph brought down many trees in the Groton cemetery. Some power poles along with many tree branches were also downed in Groton.
Thunderstorm Wind, Brown
- When
- July 21, 3:20 AM CST
- Where
- Brown County, 1 mi NW of Aberdeen
- Measured
- 52 kt (60 mph)
- Reported by
- EMERGENCY MANAGER
- Coordinates
- 45.483, -98.500
Thunderstorm Wind, Day
- When
- July 21, 3:27 AM CST
- Where
- Day County, 7 mi NE of Roslyn
- Measured
- 52 kt (60 mph)
- Reported by
- GENERAL PUBLIC
- Coordinates
- 45.567, -97.400
Thunderstorm Wind, Marshall
- When
- July 21, 3:50 AM CST to 4:10 AM CST
- Where
- Marshall County, 2 mi SW of Lake City
- Measured
- 78 kt (90 mph)
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 45.700, -97.450
Winds of 90 mph or higher uprooted many trees from Roy Lake to Clear Lake south of Lake City and also swept away and damaged many docks, boat lifts, and boats.
Thunderstorm Wind, Roberts
- When
- July 21, 4:17 AM CST
- Where
- Roberts County, Sisseton
- Measured
- 60 kt (69 mph)
- Reported by
- AWOS,ASOS,MESONET,ETC
- Coordinates
- 45.667, -97.050
What these are
- Thunderstorm Wind
- Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
After NWS Directive 10-1605, the rules offices file Storm Data by.
The same day elsewhere
- Lightning Strike in Wisconsin, July 21, 2002
- Wildfire in California, July 21 to 31, 2002
- Wildfire in California, July 21 to 24, 2002
- Hail and Damaging Winds in Nebraska, July 21, 2002
- Flash Flood and Hail in Nebraska, July 21, 2002
- Hail and Damaging Winds in Mississippi, July 21, 2002
- Flood and Hail in Georgia, July 21, 2002
- Damaging Winds in Minnesota, July 21, 2002
- Damaging Winds in South Dakota, July 21, 2002
- Hail and Damaging Wind in Iowa, July 21, 2002
- Damaging Winds in Minnesota, July 21, 2002
- Damaging Winds in Iowa, July 21, 2002
More
Every storm in South Dakota in 2002Every state in 2002This day in weather historyWarnings in South Dakota, July 2002
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: 5309484, 5309481, 5309485, 5309486, 5309487, 5309488, 5309491, 5309482, 5309489, 5309490, 5309483.