Flash Flood Warning issued Oct. 9, 2026 by NWS Sioux Falls SD

NWS Sioux Falls SD issued a Flash Flood Warning at 12:15 a.m. MDT (1:15 a.m. CDT) Oct. 9, 2026, according to the National Weather Service's public alert record.

The alert states that it takes effect at 12:15 a.m. MDT (1:15 a.m. CDT), gives the onset as 12:15 a.m. MDT (1:15 a.m. CDT) and expires at 3:15 a.m. MDT (4:15 a.m. CDT). It may reach both of South Dakota's time zones, so each time is given in both.

The alert separately states that the hazard itself ends at 3:15 a.m. MDT (4:15 a.m. CDT), which can differ from when the message expires.

Whether this alert is currently in effect is not stated in this text, deliberately: it depends on the time you are reading, so it is computed from the expiry above each time the page is loaded, rather than stored as an answer that would go out of date without anyone noticing. The status shown at the top of this page is the computed one.

The issuing office classified this message as severity "Severe", certainty "Likely" and urgency "Immediate". Those are the National Weather Service's own categories, reproduced exactly, not re-ranked or translated into another scale.

The recommended response type on the message is "Avoid".

The alert names these areas: Sioux, Iowa; Union, South Dakota. The National Weather Service zone codes are IAC167 and SDC127.

The full text of the alert as issued at 12:15 a.m. MDT (1:15 a.m. CDT), reproduced without changes:

FFWFSD

The National Weather Service in Sioux Falls has issued a

* Flash Flood Warning for... Southwestern Sioux County in northwestern Iowa... Northeastern Union County in southeastern South Dakota...

* Until 415 AM CDT.

* At 115 AM CDT, Doppler radar and automated rain gauges indicated thunderstorms producing heavy rain across the warned area. Between 2 and 3.5 inches of rain have fallen. The expected rainfall rate is 1.5 to 3 inches in 1 hour. Additional rainfall amounts up to 1 inch are possible in the warned area. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar and automated gauges.

IMPACT...Flash flooding of small creeks and streams, urban areas, highways, streets and underpasses as well as other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include... Hawarden and Alcester.

The protective-action text the issuing office attached, reproduced without changes:

Turn around, don't drown when encountering flooded roads. Most flood deaths occur in vehicles.

Be especially cautious at night when it is harder to recognize the dangers of flooding.

Be aware of your surroundings and do not drive on flooded roads.

Please report observed flooding to local emergency services or law enforcement and request they pass this information to the National Weather Service when you can do so safely.

The National Weather Service superseded this message at 3:14 a.m. MDT (4:14 a.m. CDT) with a later one. This article records the message as issued.

This alert is a work of the United States federal government — the National Weather Service, part of NOAA — and is in the public domain; no copyright is claimed on it and none is asserted here. The alert is reproduced without added meteorological judgement. For live conditions and alerts, go to the National Weather Service.

Only alerts the National Weather Service gave a window of two hours or longer appear here, checked once a day. Short-notice warnings — including tornado and severe thunderstorm warnings, which the service typically issues for under an hour — are NOT carried here, so their absence here says nothing about whether one was issued. For those, and for live conditions, go to the National Weather Service.