South Dakota, 2020

Flood in South Dakota, April 2 to 12, 2020

April 2 to 12, 2020 · NWS ABR · 1 event in 1 county or zone

5 feet on April 3rd and then falling back to below flood stage on April 12th.

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

Open the live radar over this ground

The toll

Deaths
0
Injuries
0
Property damage
None recorded
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 ABR wrote it up.

The Big Sioux River near Castlewood went above the flood stage of 9 feet on April 2nd rising to 9.5 feet on April 3rd and then falling back to below flood stage on April 12th.

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 Apr 1, 2:13 PM CST, 15 hours 47 minutes earlier.

Area forecast discussion, Apr 1, 2:13 PM CST, 15 hours 47 minutes before
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Hazardous weather outlook, Apr 1, 1:55 PM CST, 16 hours 5 minutes before
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The radar

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

Open the radar archive at this moment

Event by event

1 flood. Local standard time, as filed.

Flood, Hamlin

When
April 2, 6:00 AM CST to April 12, 11:30 AM CST
Where
Hamlin County, 5.78 mi ENE of Thomas to 2.86 mi N of Castlewood
Cause
Heavy Rain / Snow Melt
Reported by
River/Stream Gage
Coordinates
44.800, -97.090

What these are

Flood
Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in South Dakota in 2020Every state in 2020This day in weather historyWarnings in South Dakota, April 2020

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 2026-09-30. Each event’s entry at NCEI: 889744.