Alert archive / Iowa / Severe Thunderstorm Warnings in 2026
Severe Thunderstorm Warning 49, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at May 17, 2026, 7:32 PM CDT for Dakota County, Nebraska; Union County, South Dakota; 4 counties in Iowa. It was in force for 58 min. 31 reports came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- May 17, 2026, 7:32 PM CDT (00:32 UTC)
- Expired
- May 17, 2026, 8:30 PM CDT
- In force
- 58 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Storm-based polygon
- Tornado
- Possible
- Damage threat
- Considerable
- Hail
- 1.0 in
- Wind
- 70.0 mph
Counties Cherokee County, IA, Ida County, IA, Plymouth County, IA, Woodbury County, IA, Dakota County, NE, Union County, SD
The radar
The Omaha radar (KOAX), 130 km from the middle of the area, began a volume at 00:34 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 17, 7:32 PM CDT | TSTM WND DMG | 3 Se Sioux City, IA | Several photos via social media of large tree branches down in the Morningside neighborhood. |
| May 17, 7:35 PM CDT | TORNADO | 3 Ne Sergeant Bluff, IA | Several videos via social media of brief gustnado. Location estimated. |
| May 17, 7:36 PM CDT | TSTM WND GST 66 | 4 Nne Sergeant Bluff, IA | Via personal weather station. Exact time estimated via radar. |
| May 17, 7:36 PM CDT | TSTM WND GST 66 | 4 Nne Sergeant Bluff, IA | Via personal weather station. Exact time estimated via radar. |
| May 17, 7:48 PM CDT | TSTM WND GST 67 | Lawton, IA | Via personal weather station. |
| May 17, 7:48 PM CDT | TSTM WND GST 67 | Lawton, IA | Via personal weather station. |
| May 17, 7:49 PM CDT | TSTM WND GST 63 | Moville, IA | Via personal weather station. |
| May 17, 7:49 PM CDT | TSTM WND GST 63 | Moville, IA | Via personal weather station. |
| May 17, 7:50 PM CDT | TSTM WND GST 77 | Moville, IA | Via personal weather station. Exact time estimated via radar. |
| May 17, 7:50 PM CDT | TSTM WND GST 77 | Moville, IA | Via personal weather station. Exact time estimated via radar. |
| May 17, 7:51 PM CDT | TSTM WND DMG | Moville, IA | Several videos and photos via social media of large trees down, including some on houses or other structures. |
| May 17, 7:54 PM CDT | TSTM WND GST 74 | 4 W Correctionville, IA | Via personal weather station. Exact time estimated via radar. |
| May 17, 7:54 PM CDT | TSTM WND GST 74 | 4 W Correctionville, IA | Via personal weather station. Exact time estimated via radar. |
| May 17, 7:56 PM CDT | TSTM WND GST 75 | 3 Ne Moville, IA | Via personal weather station. Exact time estimated via radar. |
| May 17, 7:56 PM CDT | TSTM WND GST 75 | 3 Ne Moville, IA | Via personal weather station. Exact time estimated via radar. |
| May 17, 7:56 PM CDT | TORNADO | 5 Nw Kingsley, IA | Kingsley Fire reported brief tornado near C60 and Pioneer Ave. |
| May 17, 7:56 PM CDT | TORNADO | 5 Nw Kingsley, IA | Kingsley Fire reported brief tornado near C60 and Pioneer Ave. |
| May 17, 7:57 PM CDT | TSTM WND GST 74 | 1 Sw Pierson, IA | Via personal weather station. Exact time estimated via radar. |
| May 17, 7:57 PM CDT | TSTM WND GST 74 | 1 Sw Pierson, IA | Via personal weather station. Exact time estimated via radar. |
| May 17, 8:03 PM CDT | TSTM WND DMG | 3 Ne Pierson, IA | Photos via social media of destroyed outbuilding and tree damage 6 miles west of Washta. |
| May 17, 8:03 PM CDT | TSTM WND GST 88 | Correctionville, IA | Via personal weather station. Exact time estimated via radar. |
| May 17, 8:12 PM CDT | TORNADO | 7 S Marcus, IA | Video of brief gustnado. Location estimated. |
| May 17, 8:15 PM CDT | TORNADO | 3 W Cherokee, IA | A couple of videos via social media of brief gustnado. Location estimated. |
| May 17, 8:22 PM CDT | TSTM WND GST 59 | 1 Nnw Ida Grove, IA | Mesonet station RIGI4 Ida Grove. |
| May 17, 8:22 PM CDT | TSTM WND GST 59 | 1 Nnw Ida Grove, IA | Mesonet station RIGI4 Ida Grove. |
| May 17, 8:26 PM CDT | TORNADO | 3 Ne Meriden, IA | Storm chasers reported a brief tornado on the ground 2 to 3 minutes. Time and location confirmed with radar. |
| May 17, 8:26 PM CDT | TORNADO | 3 Ne Meriden, IA | Storm chasers reported a brief tornado on the ground 2 to 3 minutes. Time and location confirmed with radar. |
| May 17, 8:29 PM CDT | TSTM WND GST 62 | 1 S Cherokee, IA | AWOS station KCKP Cherokee Municipal Airport. |
| May 17, 8:29 PM CDT | TSTM WND GST 62 | 1 S Cherokee, IA | AWOS station KCKP Cherokee Municipal Airport. |
| May 17, 8:31 PM CDT | TSTM WND GST 60 | Meriden, IA | Via personal weather station. |
| May 17, 8:31 PM CDT | TSTM WND GST 60 | Meriden, IA | Via personal weather station. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| May 17, 1:42 PM CDT | Tornado Watch | SPC | 8 hr |
The nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 0.5 hours before the alert went out and 130 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 2478 J/kg
- Mixed-layer CIN
- -15 J/kg
- Mixed-layer LCL
- 1258 m above ground
- 0-6 km bulk shear
- 34 kt
- 0-1 km storm-relative helicity
- 178 m²/s²
- 0-3 km storm-relative helicity
- 298 m²/s²
- Significant tornado parameter
- 2.0
- Supercell composite
- 17.9
The text
As transmitted.
188
WUUS53 KFSD 180032
SVRFSD
IAC035-093-149-193-NEC043-SDC127-180130-
/O.NEW.KFSD.SV.W.0049.260518T0032Z-260518T0130Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
732 PM CDT Sun May 17 2026
The National Weather Service in Sioux Falls has issued a
* Severe Thunderstorm Warning for...
Cherokee County in northwestern Iowa...
Woodbury County in west central Iowa...
Eastern Plymouth County in northwestern Iowa...
Ida County in west central Iowa...
Dakota County in northeastern Nebraska...
Southeastern Union County in southeastern South Dakota...
* Until 830 PM CDT.
* At 732 PM CDT, severe thunderstorms were located along a line
extending from near Sioux City to Salix to near Macy, moving
northeast at 60 mph.
HAZARD...70 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Hail damage to vehicles is expected. Expect considerable
tree damage. Wind damage is also likely to mobile homes,
roofs, and outbuildings.
* Severe thunderstorms will be near...
Moville, Sloan, Hinton, Lawton, and Hornick around 740 PM CDT.
Kingsley, Anthon, and Smithland around 750 PM CDT.
Other locations in the path of these severe thunderstorms include
Remsen, Correctionville, Pierson, Marcus, Washta, Quimby, Cleghorn,
Cushing, Cherokee, Holstein and Aurelia.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.
Prepare immediately for large hail and damaging winds. People outside
should move immediately to shelter inside a strong building. Stay
away from windows.
A Tornado Watch remains in effect until 1000 PM CDT for northwestern
and west central Iowa...northeastern Nebraska...and southeastern
South Dakota.
&&
LAT...LON 4222 9632 4227 9635 4228 9671 4248 9672
4291 9597 4291 9587 4278 9540 4221 9543
TIME...MOT...LOC 0032Z 232DEG 51KT 4254 9636 4231 9626 4211 9627
TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH
$$
BP3 follow-up statements
965
WWUS53 KFSD 180040
SVSFSD
Severe Weather Statement
National Weather Service Sioux Falls SD
740 PM CDT Sun May 17 2026
IAC035-093-149-193-NEC043-SDC127-180130-
/O.CON.KFSD.SV.W.0049.000000T0000Z-260518T0130Z/
Cherokee IA-Woodbury IA-Plymouth IA-Ida IA-Dakota NE-Union SD-
740 PM CDT Sun May 17 2026
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM CDT
FOR CHEROKEE...WOODBURY...EASTERN PLYMOUTH...IDA...EASTERN DAKOTA AND
SOUTHEASTERN UNION COUNTIES...
At 739 PM CDT, severe thunderstorms were located along a line
extending from near Sioux City to 7 miles northeast of Salix to near
Whiting, moving northeast at 60 mph.
HAZARD...70 mph wind gusts and half dollar size hail.
SOURCE...Mesonet. At 731 PM CDT, a personal weather station near
Salix, IA reported a 69 mph wind gust.
IMPACT...Hail damage to vehicles is expected. Expect considerable
tree damage. Wind damage is also likely to mobile homes,
roofs, and outbuildings.
These severe storms will be near...
Moville, Hinton, Lawton, and Hornick around 745 PM CDT.
Kingsley, Merrill, Anthon, and Smithland around 750 PM CDT.
Other locations in the path of these severe thunderstorms include Le
Mars, Pierson, Remsen, Correctionville, Washta, Quimby, Cushing,
Marcus, Cleghorn, Cherokee, Holstein and Aurelia.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A Tornado Watch remains in effect until 1000 PM CDT for northwestern
and west central Iowa...northeastern Nebraska...and southeastern
South Dakota.
Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.
Prepare immediately for large hail and damaging winds. People outside
should move to a shelter, inside a strong building and away from
windows.
&&
LAT...LON 4222 9632 4227 9635 4237 9661 4251 9664
4291 9597 4291 9587 4278 9540 4221 9543
TIME...MOT...LOC 0039Z 231DEG 51KT 4256 9637 4237 9617 4217 9618
TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.25 IN
WIND THREAT...OBSERVED
MAX WIND GUST...70 MPH
$$
BP433
WWUS53 KFSD 180056
SVSFSD
Severe Weather Statement
National Weather Service Sioux Falls SD
756 PM CDT Sun May 17 2026
NEC043-SDC127-180105-
/O.CAN.KFSD.SV.W.0049.000000T0000Z-260518T0130Z/
Dakota NE-Union SD-
756 PM CDT Sun May 17 2026
...THE SEVERE THUNDERSTORM WARNING FOR EASTERN DAKOTA AND
SOUTHEASTERN UNION COUNTIES IS CANCELLED...
The storms which prompted the warning have moved out of the warned
area. Therefore, the warning has been cancelled.
A Tornado Watch remains in effect until 1000 PM CDT for northwestern
and west central Iowa...northeastern Nebraska...and southeastern
South Dakota.
&&
LAT...LON 4222 9632 4232 9637 4234 9641 4241 9641
4244 9638 4249 9640 4249 9648 4260 9650
4291 9597 4291 9587 4278 9540 4221 9543
TIME...MOT...LOC 0055Z 236DEG 68KT 4269 9617 4250 9592 4230 9586
$$
IAC035-093-149-193-180130-
/O.CON.KFSD.SV.W.0049.000000T0000Z-260518T0130Z/
Cherokee IA-Woodbury IA-Plymouth IA-Ida IA-
756 PM CDT Sun May 17 2026
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM CDT
FOR CHEROKEE...WOODBURY...EASTERN PLYMOUTH AND IDA COUNTIES...
At 755 PM CDT, severe thunderstorms were located along a line
extending from near Merrill to near Pierson to near Smithland, moving
northeast at 80 mph.
HAZARD...70 mph wind gusts and half dollar size hail.
SOURCE...Mesonet. At 748 PM CDT, a 67 mph wind gust was reported
by a personal weather station in Moville, IA.
IMPACT...Hail damage to vehicles is expected. Expect considerable
tree damage. Wind damage is also likely to mobile homes,
roofs, and outbuildings.
These severe storms will be near...
Remsen, Kingsley, Correctionville, Pierson, Washta, and Cushing
around 800 PM CDT.
Other locations in the path of these severe thunderstorms include
Holstein, Marcus, Quimby, Cherokee, Galva, Cleghorn and Aurelia.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.
Prepare immediately for large hail and damaging winds. People outside
should move to a shelter, inside a strong building and away from
windows.
&&
LAT...LON 4222 9632 4232 9637 4234 9641 4241 9641
4244 9638 4249 9640 4249 9648 4260 9650
4291 9597 4291 9587 4278 9540 4221 9543
TIME...MOT...LOC 0055Z 236DEG 68KT 4269 9617 4250 9592 4230 9586
TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.25 IN
WIND THREAT...OBSERVED
MAX WIND GUST...70 MPH
$$
BP930
WWUS53 KFSD 180113
SVSFSD
Severe Weather Statement
National Weather Service Sioux Falls SD
813 PM CDT Sun May 17 2026
IAC035-093-149-193-180130-
/O.CON.KFSD.SV.W.0049.000000T0000Z-260518T0130Z/
Cherokee IA-Woodbury IA-Plymouth IA-Ida IA-
813 PM CDT Sun May 17 2026
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM CDT
FOR CHEROKEE...EASTERN WOODBURY...EASTERN PLYMOUTH AND IDA
COUNTIES...
At 812 PM CDT, severe thunderstorms were located along a line
extending from Remsen to near Quimby to near Cushing, moving
northeast at 60 mph.
THESE ARE DESTRUCTIVE STORMS FOR KINGSLEY, CORRECTIONVILLE, WASHTA,
AND QUIMBY.
HAZARD...80 mph wind gusts and quarter size hail.
SOURCE...Mesonet. At 752 PM CDT, a 77 mph wind gust was reported via
personal weather station in Moville, Iowa.
IMPACT...Flying debris will be dangerous to those caught without
shelter. Mobile homes will be heavily damaged. Expect
considerable damage to roofs, windows, and vehicles.
Extensive tree damage and power outages are likely.
These severe storms will be near...
Cherokee, Holstein, Marcus, Quimby, and Cleghorn around 815 PM
CDT.
Other locations in the path of these severe thunderstorms include
Aurelia and Galva.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
This is an EXTREMELY DANGEROUS SITUATION with tornado like wind
speeds expected. Mobile homes and high profile vehicles are
especially susceptible to winds of this magnitude and may be
overturned. For your protection move to an interior room on the
lowest floor of a building. These storms have the potential to cause
serious injury and significant property damage.
&&
LAT...LON 4222 9597 4272 9630 4291 9597 4291 9587
4278 9540 4221 9543
TIME...MOT...LOC 0112Z 232DEG 51KT 4281 9595 4262 9570 4242 9564
TORNADO...POSSIBLE
THUNDERSTORM DAMAGE THREAT...DESTRUCTIVE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...OBSERVED
MAX WIND GUST...80 MPH
$$
BPThe office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 17, 7:26 PM CDT | Tornado Warning | FSD | Dakota | 49 min |
| May 18, 6:08 PM CDT | Severe Thunderstorm Warning | FSD | Dakota, Dixon | 37 min |
| May 17, 7:20 PM CDT | Severe Thunderstorm Warning | FSD | Plymouth, Sioux | 28 min |
| May 17, 7:20 PM CDT | Severe Thunderstorm Warning | FSD | O'Brien, Osceola | 26 min |
| May 17, 7:47 PM CDT | Tornado Warning | FSD | Cherokee, Plymouth, Woodbury | 43 min |
| May 17, 8:00 PM CDT | Severe Thunderstorm Warning | FSD | O'Brien, Osceola, Plymouth, Sioux | 45 min |
| May 17, 8:03 PM CDT | Flash Flood Warning | FSD | Plymouth, Sioux | 3 hr |
| May 17, 8:21 PM CDT | Severe Thunderstorm Warning | FSD | Buena Vista, Cherokee, Clay, Dickinson, Ida, O'Brien and 3 more | 54 min |
| May 17, 8:26 PM CDT | Tornado Warning | FSD | Buena Vista, Cherokee, Clay, O'Brien | 28 min |
| May 17, 8:48 PM CDT | Tornado Warning | FSD | Clay, Dickinson | 27 min |
| May 17, 8:54 PM CDT | Tornado Warning | FSD | Clay, Dickinson | 51 min |
| May 18, 5:11 PM CDT | Severe Thunderstorm Warning | FSD | Cherokee, Ida, Plymouth, Woodbury | 49 min |
| May 18, 5:48 PM CDT | Severe Thunderstorm Warning | FSD | Buena Vista, Cherokee, Clay, O'Brien | 42 min |
Nearby
Severe Thunderstorm Warnings in Iowa, 2026Severe Thunderstorm Warnings in Nebraska, 2026Severe Thunderstorm Warnings in South Dakota, 2026Every severe thunderstorm warning in 2026
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.