Flooding in South Dakota, April 20 to 30, 2018

Name: Flooding in South Dakota, April 20 to 30, 2018
Start: 2018-04-20T07:00
End: 2018-04-30T23:59
Location: South Dakota

April 20 to 30, 2018 · NWS FSD · 19 events in 5 counties and zones

Much of the Big Sioux basin received from one to two inches of liquid equivalent in the week leading up to the more significant flooding, including snow melt moisture from the historic blizzard on April 14. Much of the river remained in flood at the end of the month.

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: 19

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 FSD wrote it up.

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 Sioux Falls, SD wrote its last area forecast discussion before the first event at Apr 20, 5:38 AM CST, 1 hour 22 minutes earlier.

Area forecast discussion, Apr 20, 5:38 AM CST, 1 hour 22 minutes before

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Hazardous weather outlook, Apr 20, 2:32 AM CST, 4 hours 28 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

19 flood. Local standard time, as filed.

Flood, Brookings

When: April 20, 7:00 AM CST to April 30, 11:59 PM CST
Where: Brookings County, 8.34 mi NNW of Bruce to 7.91 mi N of Bruce
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 44.544, -96.937

Snow melt and runoff from periods of heavier rainfall produced moderate flooding which produced significant impact to lowland agricultural areas. River levels reached 1.9 feet above flood stage near Estelline (gage site BSES2) on April 23. The river remained at minor flood stage at the end of the month.

Flood, Minnehaha

When: April 20, 9:00 AM CST to April 30, 11:59 PM CST
Where: Minnehaha County, 3.14 mi NNW of Renner to 2.94 mi SW of Renner
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 43.690, -96.760

Snow melt and runoff from periods of heavier rainfall produced moderate flooding which produced significant impact to lowland agricultural areas. River levels reached 4.3 feet above flood stage at Sioux Falls near Interstate 90 (gage site SFLS2) on April 28. The river remained at minor flood stage at the end of the month.

Flood, Minnehaha

When: April 20, 9:00 PM CST to April 26, 5:00 AM CST
Where: Minnehaha County, 5.22 mi NNE of Sherman to 2.36 mi N of Sherman
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 43.843, -96.453

Snow melt and runoff from periods of heavier rainfall briefly produced minor flooding with impact to lowland agricultural areas and inundated several low water crossings near the Minnesota border. River levels reached 1.6 feet above flood stage on Split Rock Creek below Jasper (gage site JSPM5) on April 21.

Flood, Brookings

When: April 20, 10:00 PM CST to April 30, 11:59 PM CST
Where: Brookings County, 8.56 mi NNW of Bruce to 7.62 mi W of Bruce
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 44.540, -96.960

Snow melt and runoff from periods of heavier rainfall produced moderate flooding which produced significant impact to lowland agricultural areas. River levels reached 2.2 feet above flood stage near Bruce (gage site BRCS2) on April 23. The river remained at minor flood stage at the end of the month.

Flood, Brookings

When: April 21, 4:00 AM CST to April 24, 5:00 PM CST
Where: Brookings County, 2.47 mi W of White to 1.47 mi NNE of (Bkx)brookings Muni
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 44.430, -96.700

Snow melt and runoff from periods of heavier rainfall briefly produced moderate flooding which produced significant impact to lowland agricultural areas and flooded several township roads northeast of Brookings. River levels reached 1.5 feet above flood stage on Sixmile Creek near Brookings (gage site SMCS2) on April 23.

Flood, Moody

When: April 21, 9:00 AM CST to April 30, 11:59 PM CST
Where: Moody County, 12.93 mi NW of Flandreau to 13.36 mi NW of Flandreau
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 44.170, -96.780

Snow melt and runoff from periods of heavier rainfall produced major flooding which produced significant impact to lowland agricultural areas. Several county roads were inundated with water as river levels reached 3.3 feet above flood stage near Brookings (gage site BRKS2) on April 24. The river remained at moderate flood stage at the end of the month.

Flood, Minnehaha

When: April 21, 9:00 AM CST to April 30, 11:59 PM CST
Where: Minnehaha County, 1 mi W of Dell Rapids to 0.69 mi NNW of Baltic
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 43.820, -96.740

Snow melt and runoff from periods of heavier rainfall produced moderate flooding which produced significant impact to lowland agricultural areas and the city park in Dell Rapids. River levels reached 2.2 feet above flood stage at Dell Rapids (gage site DERS2) on April 27. The river remained at minor flood stage at the end of the month.

Flood, Minnehaha

When: April 21, 10:00 AM CST to April 30, 11:59 PM CST
Where: Minnehaha County, 2.6 mi WNW of Brandon to 3 mi W of Brandon
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 43.590, -96.650

Snow melt and runoff from periods of heavier rainfall produced moderate flooding which produced significant impact to lowland agricultural areas. River levels reached 3.4 feet above flood stage near Brandon (gage site BBSS2) on April 28. The river remained at minor flood stage at the end of the month.

Flood, Lincoln

When: April 21, 10:00 AM CST to April 30, 11:59 PM CST
Where: Lincoln County, 3.31 mi NE of Shindler to 4.84 mi ENE of Shindler
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 43.500, -96.599

Flood, Union

When: April 21, 7:00 PM CST to April 30, 11:59 PM CST
Where: Union County, 6.93 mi NE of Alcester to 10.62 mi SE of Big Spgs
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 43.080, -96.540

Snow melt and runoff from periods of heavier rainfall produced moderate flooding which produced significant impact to lowland agricultural areas, and inundated SD Highway 46 for several days. River levels reached 5.9 feet above flood stage above Hawarden (gage site HWDI4) on April 24. The river remained at minor flood stage at the end of the month.

Flood, Union

When: April 21, 10:00 PM CST to April 30, 11:59 PM CST
Where: Union County, 1.71 mi SE of Big Spgs to 3.43 mi NW of Richland
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 42.910, -96.580

Snow melt and runoff from periods of heavier rainfall produced moderate flooding which produced significant impact to lowland agricultural areas. Several farmhouses were isolated by the high water levels. River levels reached 3.6 feet above flood stage at Akron (gage site AKRI4) on April 25. The river remained at minor flood stage at the end of the month.

Flood, Lincoln

When: April 22, 5:00 AM CST to April 30, 11:59 PM CST
Where: Lincoln County, 4.2 mi N of Canton Muni Arpt to 4.98 mi SE of Canton Muni Arpt
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 43.380, -96.557

Snow melt and runoff from periods of heavier rainfall produced minor flooding which produced significant impact to lowland agricultural areas. River levels reached 1.7 feet above flood stage at Canton (gage site CBSS2) on April 29. The river remained at minor flood stage at the end of the month.

Flood, Brookings

When: April 23, 2:00 AM CST to 8:00 PM CST
Where: Brookings County, 3.45 mi S of Bruce to 3.76 mi SW of (Bkx)brookings Muni
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 44.380, -96.880

Snow melt and runoff from periods of heavier rainfall briefly produced minor flooding which produced significant impact to lowland agricultural areas. River levels reached 0.5 feet above flood stage on North Deer Creek near Brookings (gage site NDCS2) on April 23.

Flood, Moody

When: April 23, 5:00 AM CST to April 30, 7:00 AM CST
Where: Moody County, 5.26 mi NW of Flandreau to 3.45 mi NW of Flandreau
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 44.100, -96.660

Snow melt and runoff from periods of heavier rainfall produced minor flooding which produced significant impact to lowland agricultural areas, and inundated a couple of county roads near the gage. River levels reached 2.4 feet above flood stage near Flandreau (gage site BSFS2) on April 25.

Flood, Moody

When: April 23, 9:00 AM CST to 9:00 PM CST
Where: Moody County, 7.22 mi ENE of Flandreau to 6.3 mi ENE of Flandreau
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 44.101, -96.453

Snow melt and runoff from periods of heavier rainfall briefly produced minor flooding with significant impact to lowland agricultural areas and inundated sections of the Flandreau golf course. River levels reached 1.1 feet above flood stage on Flandreau Creek near Flandreau (gage site FCRS2) on April 23.

Flood, Moody

When: April 23, 5:00 PM CST to April 30, 11:00 PM CST
Where: Moody County, 2.98 mi W of Flandreau to 1.47 mi N of Egan
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 44.050, -96.640

Snow melt and runoff from periods of heavier rainfall produced moderate flooding which produced significant impact to lowland agricultural areas, and flooded the road near the bridge near Egan Park. River levels reached 3.8 feet above flood stage near Egan (gage site EGAS2) on April 26.

Flood, Brookings

When: April 23, 10:00 PM CST to April 28, 9:00 AM CST
Where: Brookings County, 1.86 mi SE of Medary to 2.03 mi SW of (Bkx)brookings Muni
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 44.203, -96.751

Snow melt and runoff from periods of heavier rainfall produced minor flooding which produced significant impact to lowland agricultural areas. River levels reached 0.8 feet above flood stage near Medary (gage site BSMS2) on April 24.

Flood, Moody

When: April 23, 10:00 PM CST to April 28, 9:00 AM CST
Where: Moody County, 14.9 mi N of Colman to 13.36 mi N of Colman
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 44.196, -96.823

Flood, Moody

When: April 23, 10:00 PM CST to April 30, 10:00 PM CST
Where: Moody County, 1.47 mi SSE of Lone Tree to 2.76 mi SSW of Trent
Cause: Heavy Rain / Snow Melt
Reported by: River/Stream Gage
Coordinates: 43.960, -96.720

Snow melt and runoff from periods of heavier rainfall produced moderate flooding which produced significant impact to lowland agricultural areas, as well as inundated 478th Ave and 242nd St. with water reaching into backyards of several homes in Trent. River levels reached 3.0 feet above flood stage near Trent (gage site TRES2) on April 26.

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

Every storm in South Dakota in 2018 Every state in 2018 This day in weather history Warnings in South Dakota, April 2018

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: 771818, 771828, 772107, 771819, 772099, 771822, 771826, 771830, 771832, 771835, 771836, 771834, 771837, 771823, 772100, 771824, 771820, 771821, 771825.