South Dakota, 2002

Flash Flood in South Dakota, August 24, 2002

August 24, 2002 · NWS UNR · 1 event in 1 county or zone

A severe thunderstorm moved over Deadwood, producing locally heavy rain. This rainfall was in addition to rains received the past few days.

Where it happened

Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. 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

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The toll

Deaths
0
Injuries
0
Property damage
$50,000
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.

A severe thunderstorm moved over Deadwood, producing locally heavy rain. This rainfall was in addition to rains received the past few days. Steep terrain which was severely burned in a recent forest fire and had flash flooding and mudslides a few weeks earlier, experienced very rapid runoff again. Flash flooding and mudslides sent up to three feet of water, mud, and debris through downtown Deadwood. No injuries were reported, and only cosmetic damage was reported by businesses.

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 Aug 24, 1:30 PM MST, 2 hours 26 minutes earlier.

Area forecast discussion, Aug 24, 1:30 PM MST, 2 hours 26 minutes before
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
230 PM MDT SAT AUG 24 2002

MID LEVEL CIRCULATION SEEN IN WATER VAPOR PICS OVER SRN MT...WITH
TROF AXIS EXTENDING SEWD INTO WRN NEB. JET STREAK IS NOW ENTERING
WRN WY. CONVECTION ALREADY FIRING OVR WRN HALF OF CWFA WHERE CAPPING
INVERSION HAS WEAKENED SIGNIFICANTLY. HOWEVER...MID/HI LVL CLDS HAVE
KEPT CAP IN PLACE OVR WRN SD PLAINS. CONCERNS EVE REMAIN HEAVY RAIN
POTENTIAL WITH SLOW STORM MOTIONS...MAINLY EARLY THIS EVE...AS WELL
AS LARGE HAIL.

MID LEVEL TROF AXIS WILL LIFT SLOWLY NEWD ACRS CWFA THIS EVE. PLENTY
OF UVV WILL BE GENERATED FOR WIDESPREAD CONVECTIVE ACTIVITY. SHEAR
VALUES ARE MINIMAL ACRS FAR NERN ZONES...BUT INCREASE IN VALUE
TOWARDS THE SWRN ZONES. THEREFORE...EXPECT MOST INTENSE ROTATING
UPDRAFTS TO REMAIN OVR OR JUST SOUTH OF SWRN ZONES.
HOWEVER...POTENTIAL STILL IN PLACE FOR LOCALLY HEAVY RAINS AS STORM
MOTIONS WILL BE VERY SLOW...AND ALSO FOR LARGE HAIL WITH MID LVL
COLD POCKET AND LOW WET-BULB ZERO TEMPS. THE ACTIVITY WILL COME TO
AN END LATER THIS EVE IN THE SW...AND LIKELY CONT THRU THE NIGHT IN
THE NE.

NRN STREAM TROF WILL WORK SLOWLY EWD THRU NRN PLAINS/SRN CANADA
REMAINDER OF 3 DAY FCST. THIS WILL KEEP CWFA UNDER SW FLOW ALOFT FOR
CONTD UNSETTLED WX AND NEAR CLIMO TEMPS. HOWEVER...HEAVY RAIN THREAT
APPEARS TO DECREASE AS PRECIP H20 VALUES LOWER AND FASTER MID LVL
FLOW RETURNS.

EXTENDED...MED RANGE GUIDANCE SUGGESTS PAC COAST TROF MOVG LITTLE
THRU THU...THUS KEEPING CWFA IN UNSETTLED PATTERN. IT IS DIFFICULT
TO TIME SHORT WAVES SO WILL KEEP CHC PCPN IN FCST THU DAY 5. WEAK
RIDGING MAY CUT OFF MOISTURE SOURCE TOWARDS END OF WEEK.

.UNR...FLOOD WATCH CONTINUES UNTIL SAT EVE FOR BLKHLS PORTIONS OF
       LAWRENCE COUNTY.

JOHNSON

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

1 flash flood. Local standard time, as filed.

Flash Flood, Lawrence

When
August 24, 3:56 PM MST to 4:45 PM MST
Where
Lawrence County, Deadwood
Measured
3
Property damage
$50,000
Reported by
EMERGENCY MANAGER
Coordinates
44.359, -103.792 (the zone’s center; the record gives no point)

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

More

Every storm in South Dakota in 2002Every state in 2002This day in weather historyWarnings in South Dakota, August 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 2026-09-24. Each event’s entry at NCEI: 5310802.