Alert archive / South Dakota / River Flood Warnings in 2025

River Flood Warning 12, NWS Sioux Falls, SD

August 6, 2025Brookings County, Hamlin County, South Dakota

NWS Sioux Falls, SD issued this river flood warning at Aug 6, 2025, 6:38 PM CDT for Brookings County, Hamlin County, South Dakota. It was in force for 21 days.

The area

The counties it named.

The facts

Issued: Aug 6, 2025, 6:38 PM CDT (23:38 UTC)
Expired: Aug 27, 2025, 6:38 PM CDT
In force: 21 days
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Flood severity: Minor

Counties Brookings County, SD, Hamlin County, SD

The radar

The Sioux Falls radar (KFSD), 106 km from the middle of the area, began a volume at 23:36 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The river

Written for the forecast point Big Sioux River near Estelline (BSES2).

Action stage: 1642.5 ft
Minor stage: 1644 ft
Moderate stage: 1645.5 ft
Major stage: 1648 ft

This gauge today: stage, forecast and historic crests

Stage from the USGS instantaneous record, one reading an hour, from a day before the product to a day after it ended. Flood stages are today's.

What forecasters said that day

The local office's own words before this river flood warning went out, 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 this river flood warning went out at Aug 6, 6:20 PM CDT, 18 minutes earlier.

Area forecast discussion, Aug 6, 6:20 PM CDT, 18 minutes before

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Hazardous weather outlook, Aug 6, 5:19 PM CDT, 1 hour 19 minutes before

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In the hours before

Local storm report, Aug 6, 1:10 PM CDT, 5 hours 28 minutes before

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Local storm report, Aug 6, 2:02 PM CDT, 4 hours 36 minutes before

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        The site you requested is temporarily down for maintenance or an unexpected outage.
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        Please try again in a few minutes.
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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 5, 9:30 PM CDT	Severe Thunderstorm Warning	FSD	Brookings, Kingsbury	45 min
Aug 5, 10:53 PM CDT	Severe Thunderstorm Warning	FSD	Brookings, Moody	52 min
Aug 5, 11:20 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	Brookings, Kingsbury	40 min
Aug 5, 11:22 PM CDT	Severe Thunderstorm Warning	FSD	Lake, Moody	38 min
Aug 5, 11:40 PM CDT	Severe Thunderstorm Warning	FSD	Beadle, Kingsbury, Miner, Sanborn	50 min
Aug 5, 11:59 PM CDT	Severe Thunderstorm Warning	FSD	Brookings, Kingsbury, Lake, Moody	46 min
Aug 6, 12:30 AM CDT	Flash Flood Warning	FSD	Brookings, Kingsbury, Lake, Moody	3 hr
Aug 6, 10:42 AM CDT	River Flood Warning	FSD	Beadle	46 hr
Aug 6, 11:18 AM CDT	Severe Thunderstorm Warning	FSD	Aurora, Douglas	42 min

Nearby

River Flood Warnings in South Dakota, 2025 Every river flood warning in 2025

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; radar from the NEXRAD Level II archive; the gauge from the NWS water service and the USGS.