Alert archive / South Dakota / Severe Thunderstorm Warnings in 2026
Severe Thunderstorm Warning 40, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at May 17, 2026, 3:59 PM CDT for Lincoln County, Turner County, South Dakota. It was in force for 46 min. 10 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, 3:59 PM CDT (20:59 UTC)
- Expired
- May 17, 2026, 4:45 PM CDT
- In force
- 46 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Storm-based polygon
- Damage threat
- Destructive
- Hail
- 1.25 in
- Wind
- 80.0 mph
Counties Lincoln County, SD, Turner County, SD
The radar
The Sioux Falls radar (KFSD), 40 km from the middle of the area, began a volume at 20:59 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, 4:09 PM CDT | TSTM WND DMG | 3 E Parker, SD | Power poles snapped and irrigation pivots flipped near the intersection of 276th St and 456th Ave. Time estimated from radar. |
| May 17, 4:09 PM CDT | TSTM WND DMG | 3 E Parker, SD | Power poles snapped and irrigation pivots flipped near the intersection of 276th St and 456th Ave. Time estimated from radar. |
| May 17, 4:14 PM CDT | TSTM WND GST 60 | 1 S Chancellor, SD | Via personal weather station. Exact time estimated via radar. |
| May 17, 4:14 PM CDT | TSTM WND GST 60 | 1 S Chancellor, SD | Via personal weather station. Exact time estimated via radar. |
| May 17, 4:15 PM CDT | TSTM WND DMG | Chancellor, SD | 70 mph caused downed tree branches. |
| May 17, 4:15 PM CDT | TSTM WND DMG | Chancellor, SD | 70 mph caused downed tree branches. |
| May 17, 4:17 PM CDT | TSTM WND GST 70 | 2 Ene Chancellor, SD | Via personal weather station. Exact time estimated via radar. |
| May 17, 4:17 PM CDT | TSTM WND GST 70 | 2 Ene Chancellor, SD | Via personal weather station. Exact time estimated via radar. |
| May 17, 4:17 PM CDT | HAIL 1 | 2 W Lennox, SD | Quarter size hail along with estimated 40-50 mph winds reported. |
| May 17, 4:17 PM CDT | HAIL 1 | 2 W Lennox, SD | Quarter size hail along with estimated 40-50 mph winds reported. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
Did it verify
Verified. The Iowa Environmental Mesonet's Cow matched 5 storm reports to this severe thunderstorm warning; the first came 10 minutes after it went out.
Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.
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 12:00Z, 9.0 hours before the alert went out and 214 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1204 m above ground
- 0-6 km bulk shear
- 49 kt
- 0-1 km storm-relative helicity
- 38 m²/s²
- 0-3 km storm-relative helicity
- -21 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
171
WUUS53 KFSD 172059
SVRFSD
SDC083-125-172145-
/O.NEW.KFSD.SV.W.0040.260517T2059Z-260517T2145Z/
BULLETIN - EAS ACTIVATION REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
359 PM CDT Sun May 17 2026
The National Weather Service in Sioux Falls has issued a
* Severe Thunderstorm Warning for...
Lincoln County in southeastern South Dakota...
Southeastern Turner County in southeastern South Dakota...
* Until 445 PM CDT.
* At 359 PM CDT, severe thunderstorms were located along a line
extending from near Parker to near Hurley to near Viborg, moving
east at 45 mph.
HAZARD...80 mph wind gusts and half dollar size hail.
SOURCE...Radar indicated.
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.
* Severe thunderstorms will be near...
Centerville, Chancellor, and Davis around 405 PM CDT.
Lennox around 410 PM CDT.
Worthing around 415 PM CDT.
Other locations in the path of these severe thunderstorms include
Canton and Newton Hills State Park.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Prepare immediately for large hail and damaging winds. People outside
should move immediately to shelter inside a strong building. Stay
away from windows.
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.
A Tornado Watch remains in effect until 1000 PM CDT for northwestern
Iowa...and southeastern South Dakota.
&&
LAT...LON 4312 9706 4324 9701 4340 9710 4341 9656
4339 9652 4331 9652 4327 9659 4326 9655
4322 9656 4321 9647 4315 9647 4311 9644
4308 9646
TIME...MOT...LOC 2059Z 263DEG 41KT 4333 9716 4323 9712 4315 9713
THUNDERSTORM DAMAGE THREAT...DESTRUCTIVE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.25 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...80 MPH
$$
Weisser2 follow-up statements
304
WWUS53 KFSD 172131
SVSFSD
Severe Weather Statement
National Weather Service Sioux Falls SD
431 PM CDT Sun May 17 2026
SDC083-125-172145-
/O.CON.KFSD.SV.W.0040.000000T0000Z-260517T2145Z/
Lincoln SD-Turner SD-
431 PM CDT Sun May 17 2026
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 445 PM CDT
FOR LINCOLN AND SOUTHEASTERN TURNER COUNTIES...
At 430 PM CDT, severe thunderstorms were located along a line
extending from near Worthing to 7 miles west of Newton Hills State
Park to near Beresford, moving east at 40 mph.
HAZARD...80 mph wind gusts and half dollar size hail.
SOURCE...Radar indicated.
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.
Locations impacted include...
Canton, Newton Hills State Park and Hudson.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A Tornado Watch remains in effect until 1000 PM CDT for northwestern
Iowa...and southeastern South Dakota.
A tornado watch remains in effect for the warned area. Tornadoes can
develop quickly from severe thunderstorms. Although a tornado is not
immediately likely, if one is spotted act quickly and move to a place
of safety inside a sturdy structure, such as a basement or small
interior room.
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 4312 9706 4324 9701 4340 9710 4341 9656
4339 9652 4331 9652 4327 9659 4326 9655
4322 9656 4321 9647 4315 9647 4311 9644
4308 9646
TIME...MOT...LOC 2130Z 263DEG 35KT 4337 9674 4326 9672 4313 9680
THUNDERSTORM DAMAGE THREAT...DESTRUCTIVE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.25 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...80 MPH
$$
Weisser964
WWUS53 KFSD 172140
SVSFSD
Severe Weather Statement
National Weather Service Sioux Falls SD
440 PM CDT Sun May 17 2026
SDC083-125-172149-
/O.EXP.KFSD.SV.W.0040.000000T0000Z-260517T2145Z/
Lincoln SD-Turner SD-
440 PM CDT Sun May 17 2026
...THE SEVERE THUNDERSTORM WARNING FOR LINCOLN AND SOUTHEASTERN
TURNER COUNTIES WILL EXPIRE AT 445 PM CDT...
The storms which prompted the warning have moved out of the area.
Therefore, the warning will be allowed to expire. However, gusty
winds and heavy rain are still possible with these thunderstorms.
A Tornado Watch remains in effect until 1000 PM CDT for northwestern
Iowa...and southeastern South Dakota.
Remember, a Tornado Warning still remains in effect for Northern
Lincoln County until 515 pm.
&&
LAT...LON 4312 9706 4324 9701 4340 9710 4341 9656
4339 9652 4331 9652 4327 9659 4326 9655
4322 9656 4321 9647 4315 9647 4311 9644
4308 9646
TIME...MOT...LOC 2139Z 263DEG 41KT 4338 9660 4327 9658 4314 9666
$$
WeisserWhat forecasters said that day
The local office's own words before this severe thunderstorm 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 severe thunderstorm warning went out at May 17, 1:20 PM CDT, 2 hours 39 minutes earlier. Its key messages:
- There is high confidence that severe thunderstorms will develop this afternoon and evening, producing large hail, destructive straight-line winds, and a few tornadoes. An Enhanced Risk (level 3 of 5) of severe storms is in place.
- A transitioning storm mode will shift hazards from large hail and tornadoes initially, to widespread wind damage as an intense line of storms tracks east of Interstate 29 this evening.
- A lower risk of severe weather exists late Monday afternoon and evening, mainly over northwest IA, before quieter weather moves in for the mid-week period.
Area forecast discussion, May 17, 1:20 PM CDT, 2 hours 39 minutes before
Area Forecast Discussion National Weather Service Sioux Falls SD Issued by National Weather Service Lincoln IL 120 PM CDT Sun May 17 2026 .KEY MESSAGES... - There is high confidence that severe thunderstorms will develop this afternoon and evening, producing large hail, destructive straight-line winds, and a few tornadoes. An Enhanced Risk (level 3 of 5) of severe storms is in place. - A transitioning storm mode will shift hazards from large hail and tornadoes initially, to widespread wind damage as an intense line of storms tracks east of Interstate 29 this evening. - A lower risk of severe weather exists late Monday afternoon and evening, mainly over northwest IA, before quieter weather moves in for the mid-week period. && .DISCUSSION... Issued at 120 PM CDT Sun May 17 2026 The short-term convective outlook presents a highly volatile spring severe weather setup. Latest surface analysis shows a complex pattern, anchored by a strong 994 mb low over northwest KS. An inverted trough extended north of the low through central SD, while a well-defined warm front stretched northeast of the low into east central NE. A weaker low was also noted in north central NE. Visible satellite imagery revealed stable wave clouds advancing northeast over far northeast NE and extreme SE SD, ahead of the advancing warm front. Regional radar imagery showed a complex of strong to severe storms over north central NE. This storm complex is forecast by short range guidance to continue tracking east this afternoon, intensifying as interacts with the richer low- level moisture pool near and south of the warm front. Moderate to strong instability will be in place over the southern to eastern CWA by late afternoon with MLCAPE nearing 3000 J/kg. In addition, deep layer shear will increase to around 50 kt, coincident with a mid level speed max ejecting from the deep upper trough to our west. As the system evolves over the next several hours, it appears the ingredients for a significant severe weather event will be most favored over the southern to eastern CWA. Ahead of the main convective line, some CAMs show supercell development along the northward advancing warm front. These storms would present a risk of very large hail (2"+) and tornadoes. Given the amount of low level SRH/curved hodographs present, a couple strong tornadoes are possible. The convective cluster currently entering our far southwest CWA should strengthen as it shifts east, with an initial hail and tornado threat transitioning to a damaging straight line wind threat (70+ MPH) as it grows upscale into a squall line/QLCS. Some line-embedded QLCS tornadoes are possible, especially for any line segments that become oriented north/south or northwest/southeast, given southwesterly 0-3 km shear vectors. Timing from latest high-res guidance suggests this activity exits to the east of our CWA late this evening. Precipitation amounts will vary significantly based on convective tracks, though NBM guidance and HREF probability match mean fields project a widespread 0.50 to 1.50 inches of rainfall, particularly across northwest Iowa and southwest Minnesota. On Monday, the cold front finally pushes into the area. Instability and shear are forecast to be much lower than today, however, there will be a conditional risk of severe storms over the eastern CWA during the late afternoon to evening, if the airmass can destabilize sufficiently ahead of the front. SPC's Day 2 outlook indicates as Marginal Risk (level 1 of 5), for our MN and IA counties. Behind the departing upper wave, quasi-zonal flow sets up for Tuesday and Wednesday, yielding quiet conditions and seasonally cool high temperatures moderating from the upper 50s Tuesday to mid-upper 60s Wednesday. The next upper wave moves in for the Thursday to Friday period, however Gulf moisture remains cutoff ahead of this system. Evaluating the ECMWF Extreme Forecast Index (EFI) reveals no significant climatological anomalies for precipitation or wind across the upper Midwest during this period, reinforcing the the idea of a low-impact system for our area. The current forecast sticks closely to the NBM consensus, maintaining broad 20-30 percent probabilities for light rain for late Thursday into Saturday. By late this week and especially this weekend, temperatures will embark on a steady upward trajectory, as the mid level flow backs west, then southwest. The Climate Prediction Center (CPC) 6-10 day outlook favors above-normal temperatures across the Northern Plains and Upper Midwest, which supports blended guidance high temperatures reaching well into the 80s on Sunday. && .AVIATION /18Z TAFS THROUGH 18Z MONDAY/... Issued at 1248 PM CDT Sun May 17 2026 Showers and storms move through the region this afternoon into tonight. Intermittent MVFR/IFR conditions will be possible throughout this timeframe, especially in heavier rain. TSRA was included at least in PROB30 groups, but is expected to be the dominant weather type at times. Widespread MVFR/IFR cigs setting in overnight for much of Monday. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...None. MN...None. IA...None. NE...None. && DISCUSSION...ILX/25 AVIATION...DYE
Hazardous weather outlook, May 17, 1:29 PM CDT, 2 hours 30 minutes before
Hazardous Weather Outlook National Weather Service Sioux Falls SD Issued by National Weather Service Lincoln IL 129 PM CDT Sun May 17 2026 IAZ001>003-012>014-020>022-031-032-MNZ071-072-080-081-089-090-097- 098-NEZ013-014-SDZ038>040-050-052>071-181830- Lyon-Osceola-Dickinson-Sioux-O'Brien-Clay-Plymouth-Cherokee- Buena Vista-Woodbury-Ida-Lincoln-Murray-Cottonwood-Nobles-Jackson- Pipestone-Rock-Dixon-Dakota-Beadle-Kingsbury-Brookings-Gregory- Jerauld-Sanborn-Miner-Lake-Moody-Brule-Aurora-Davison-Hanson-McCook- Minnehaha-Charles Mix-Douglas-Hutchinson-Turner-Bon Homme-Yankton- Union- 129 PM CDT Sun May 17 2026 This Hazardous Weather Outlook is for northwest Iowa, west central Iowa, southwest Minnesota, northeast Nebraska, central South Dakota, east central South Dakota, south central South Dakota and southeast South Dakota. .DAY ONE...This afternoon and tonight. A significant severe weather event is possible this afternoon and evening. Very large hail, damaging wind gusts, and tornadoes are all possible. If you have outdoor plans know where your nearest shelter is located. Please ensure you have multiple ways to receive warnings. Have a plan to take shelter and act immediately if your area comes under a severe weather warning. .DAYS TWO THROUGH SEVEN...Monday through Saturday. Strong to severe storms are possible again Monday afternoon and evening, particularly over northwest Iowa and southwest Minnesota. .SPOTTER INFORMATION STATEMENT... Spotter activation will likely be needed this afternoon and evening.
In the hours before
Local storm report, May 17, 3:51 PM CDT, 8 minutes before
Preliminary Local Storm Report
National Weather Service Sioux Falls SD
351 PM CDT Sun May 17 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0344 PM Hail 3 E Menno 43.22N 97.51W
05/17/2026 M1.00 Inch Hutchinson SD Public
Via mping. Time estimated via radar.
&&
akLocal storm report, May 17, 3:52 PM CDT, 7 minutes before
Preliminary Local Storm Report
National Weather Service Sioux Falls SD
352 PM CDT Sun May 17 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0344 PM Hail 7 N Mayfield 43.18N 97.34W
05/17/2026 E1.00 Inch Turner SD Public
Via mping. Time estimated via radar.
&&
akLocal storm report, May 17, 3:54 PM CDT, 5 minutes before
Preliminary Local Storm Report
National Weather Service Sioux Falls SD
354 PM CDT Sun May 17 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0338 PM Tstm Wnd Gst 7 ESE Menno 43.21N 97.45W
05/17/2026 M81 MPH Hutchinson SD Mesonet
Mesonet station MNMS2 Menno 7ESE (SD
Mesonet).
&&
akLocal storm report, May 17, 3:55 PM CDT, 4 minutes before
Preliminary Local Storm Report
National Weather Service Sioux Falls SD
355 PM CDT Sun May 17 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0315 PM Tstm Wnd Dmg 2 S Tyndall 42.96N 97.86W
05/17/2026 Bon Homme SD Trained Spotter
65 to 70 mph downed small trees. Quarter
sized hail also occurred.
&&
THLocal storm report, May 17, 3:58 PM CDT, 1 minute before
Preliminary Local Storm Report
National Weather Service Sioux Falls SD
358 PM CDT Sun May 17 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0342 PM Tstm Wnd Gst 5 S Freeman 43.28N 97.42W
05/17/2026 M82 MPH Hutchinson SD Mesonet
Mesonet station 163 SD RWIS Freeman.
&&
akLocal storm report, May 17, 3:59 PM CDT, 0 minutes before
Preliminary Local Storm Report
National Weather Service Sioux Falls SD
359 PM CDT Sun May 17 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0347 PM Tstm Wnd Gst 9 W Hurley 43.26N 97.27W
05/17/2026 E60 MPH Turner SD Trained Spotter
Spotter estimated 50-60 mph winds along with
half dollar size hail.
&&
MMThe office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 17, 1:10 AM CDT | Flash Flood Warning | FSD | Union | 4 hr |
| May 17, 1:09 PM CDT | Severe Thunderstorm Warning | FSD | Gregory | 51 min |
| May 17, 2:10 PM CDT | Severe Thunderstorm Warning | FSD | Charles Mix, Gregory | 50 min |
| May 17, 2:15 PM CDT | Severe Thunderstorm Warning | FSD | Aurora, Brule, Charles Mix, Douglas | 45 min |
| May 17, 2:49 PM CDT | Severe Thunderstorm Warning | FSD | Bon Homme, Hutchinson, Yankton | 41 min |
| May 17, 2:50 PM CDT | Tornado Warning | FSD | Bon Homme, Charles Mix, Hutchinson | 40 min |
| May 17, 3:23 PM CDT | Tornado Warning | FSD | Hutchinson, Turner, Yankton | 52 min |
| May 17, 3:28 PM CDT | Severe Thunderstorm Warning | FSD | Bon Homme, Clay, Hutchinson, Turner, Yankton | 47 min |
| May 17, 3:35 PM CDT | Tornado Warning | FSD | Hutchinson, Turner | 28 min |
| May 17, 4:18 PM CDT | Severe Thunderstorm Warning | FSD | Lincoln, Minnehaha, Turner | 42 min |
| May 17, 4:27 PM CDT | Tornado Warning | FSD | Lincoln, Minnehaha | 48 min |
| May 17, 4:56 PM CDT | Severe Thunderstorm Warning | FSD | Minnehaha | 49 min |
Nearby
Severe 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.