NWS Sioux Falls SDFW.W 0010April 21, 2026
Red Flag Warning: Lyon, Osceola, Sioux and 21 more, IA and MN
The National Weather Service office in Sioux Falls issued a red flag warning for Lyon, Osceola, Sioux and 21 more in Iowa, Minnesota, Nebraska, South Dakota, which was in force until 8:00 p.m. local time on April 22. It was the 10th red flag warning the NWS office in Sioux Falls issued in 2026. Iowa had 5 red flag warnings in April 2026, against 5 in an average April of 2008-2025 (Iowa's red flag warnings by year).
ExpiredWarning
In force for 8 hours; it has expired. The agency may have replaced it with a new notice.
The notice
- Issued by
- National Weather Service, Sioux Falls SD
- Area
- Lyon, Osceola, Sioux and 21 more
- State
- Iowa
- Level
- Warning
- Issued
- 12:54 p.m. CDT, April 21, 2026
- In force from
- 12:00 p.m. CDT, April 22, 2026
- Expires
- 8:00 p.m. CDT, April 22, 2026
- CAP severity, certainty, urgency
- Severe, Likely, Expected
- VTEC event
- KFSD FW.W 0010
- Official source
- National Weather Service: the notice at its source
Source: National Weather Service: the notice at its source. AreaZine rebuilds this page from the agency's record; the agency's page is the one to act on. A U.S. Government work, in the public domain.
The notice as issued
The National Weather Service in Sioux Falls has issued a Red Flag Warning for wind and low relative humidity, which is in effect from noon to 8 PM CDT Wednesday. * AFFECTED AREA...In Iowa, Lyon, Osceola and Sioux. In Minnesota, Lincoln, Lyon, Murray, Cottonwood, Nobles, Jackson, Pipestone and Rock. In Nebraska, Dixon and Dakota. In South Dakota, Kingsbury, Brookings, Miner, Lake, Moody, McCook, Minnehaha, Turner, Lincoln, Clay and Union. * WINDS...South 20 to 30 mph with gusts up to 40 mph. * RELATIVE HUMIDITY...As low as 20 percent. * IMPACTS...Any fire that develops will catch and spread quickly. Outdoor burning is not recommended.
What the agency told people to do
A Red Flag Warning means that critical fire weather conditions are either occurring now, or will shortly. A combination of strong winds, low relative humidity, and warm temperatures can contribute to extreme fire behavior.
Source: National Weather Service: the notice at its source. The text is the agency's, unedited. A U.S. Government work, in the public domain.