Alert archive / Iowa / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 4, NWS Sioux Falls, SD

April 13, 2026Plymouth County, Sioux County, Woodbury County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Apr 13, 2026, 5:26 PM CDT for Plymouth County, Sioux County, Woodbury County, Iowa. It was in force for 49 min. 3 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
Apr 13, 2026, 5:26 PM CDT (22:26 UTC)
Expired
Apr 13, 2026, 6:15 PM CDT
In force
49 min
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Plymouth County, IA, Sioux County, IA, Woodbury County, IA

The radar

The Sioux Falls radar (KFSD), 111 km from the middle of the area, began a volume at 22:26 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

TimeReportWhereRemark
Apr 13, 5:37 PM CDTHAIL 1.257 S Remsen, IA
Apr 13, 5:42 PM CDTHAIL 2.755 Ssw Remsen, IA
Apr 13, 6:10 PM CDTHAIL 1.754 S Remsen, IA

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 3 storm reports to this severe thunderstorm warning; the first came 11 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.

IssuedProductOfficeLasted
Apr 13, 4:39 PM CDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 10.4 hours before the alert went out and 306 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.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 2026-04-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 8 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 12:00Z on 2026-04-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 124 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
8 J/kg
Mixed-layer CIN
-259 J/kg
Mixed-layer LCL
1506 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
124 m²/s²
0-3 km storm-relative helicity
229 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

597 
WUUS53 KFSD 132226
SVRFSD
IAC149-167-193-132315-
/O.NEW.KFSD.SV.W.0004.260413T2226Z-260413T2315Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Sioux Falls SD
526 PM CDT Mon Apr 13 2026

The National Weather Service in Sioux Falls has issued a

* Severe Thunderstorm Warning for...
  North central Woodbury County in west central Iowa...
  Southeastern Sioux County in northwestern Iowa...
  Eastern Plymouth County in northwestern Iowa...

* Until 615 PM CDT.

* At 526 PM CDT, a severe thunderstorm was located near Kingsley, or
  12 miles south of Le Mars, moving north at 40 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* This severe thunderstorm will be near...
  Le Mars around 530 PM CDT.
  Remsen around 535 PM CDT.

Other locations in the path of this severe thunderstorm include
Alton, Orange City and Granville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

To report severe weather, contact your nearest law enforcement
agency. They will send your report to the National Weather Service
office in Sioux Falls.

&&

LAT...LON 4253 9621 4305 9614 4301 9586 4276 9585
      4250 9592
TIME...MOT...LOC 2226Z 192DEG 36KT 4261 9607 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

IG
3 follow-up statements
529 
WWUS53 KFSD 132230
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
530 PM CDT Mon Apr 13 2026

IAC193-132240-
/O.CAN.KFSD.SV.W.0004.000000T0000Z-260413T2315Z/
Woodbury IA-
530 PM CDT Mon Apr 13 2026

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL WOODBURY COUNTY
IS CANCELLED...

The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 1000 PM CDT for
northwestern Iowa.

&&

LAT...LON 4261 9619 4305 9614 4301 9586 4276 9585
      4258 9590
TIME...MOT...LOC 2230Z 190DEG 31KT 4265 9606 

$$

IAC149-167-132315-
/O.CON.KFSD.SV.W.0004.000000T0000Z-260413T2315Z/
Sioux IA-Plymouth IA-
530 PM CDT Mon Apr 13 2026

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM CDT
FOR SOUTHEASTERN SIOUX AND EASTERN PLYMOUTH COUNTIES...

At 530 PM CDT, a severe thunderstorm was located near Kingsley, or 10
miles southeast of Le Mars, moving north at 35 mph.

HAZARD...Two inch hail and 60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect wind 
         damage to roofs, siding, and trees.

This severe storm will be near...
  Le Mars and Remsen around 535 PM CDT.

Other locations in the path of this severe thunderstorm include
Orange City, Alton and Granville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Sioux Falls.

&&

LAT...LON 4261 9619 4305 9614 4301 9586 4276 9585
      4258 9590
TIME...MOT...LOC 2230Z 190DEG 31KT 4265 9606 

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...2.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

IG
423 
WWUS53 KFSD 132242
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
542 PM CDT Mon Apr 13 2026

IAC149-167-132315-
/O.CON.KFSD.SV.W.0004.000000T0000Z-260413T2315Z/
Sioux IA-Plymouth IA-
542 PM CDT Mon Apr 13 2026

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM CDT
FOR SOUTHEASTERN SIOUX AND NORTHEASTERN PLYMOUTH COUNTIES...

At 542 PM CDT, a severe thunderstorm was located near Remsen, or 10
miles east of Le Mars, moving northeast at 40 mph.

HAZARD...Two inch hail and 60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect wind 
         damage to roofs, siding, and trees.

This severe storm will be near...
  Remsen around 545 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This storm is producing large hail. SEEK SHELTER NOW inside a sturdy
structure and stay away from windows.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Sioux Falls.

&&

LAT...LON 4266 9618 4295 9615 4295 9586 4289 9586
      4278 9585 4277 9585 4273 9586 4263 9589
TIME...MOT...LOC 2242Z 208DEG 37KT 4276 9596 

THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...2.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

IG
989 
WWUS53 KFSD 132247
SVSFSD

Severe Weather Statement
National Weather Service Sioux Falls SD
547 PM CDT Mon Apr 13 2026

IAC149-167-132315-
/O.CON.KFSD.SV.W.0004.000000T0000Z-260413T2315Z/
Sioux IA-Plymouth IA-
547 PM CDT Mon Apr 13 2026

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM CDT
FOR SOUTHEASTERN SIOUX AND NORTHEASTERN PLYMOUTH COUNTIES...

At 547 PM CDT, a severe thunderstorm was located over Remsen, or 11
miles east of Le Mars, moving north at 40 mph.

HAZARD...Ping pong ball size hail and 60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...People and animals outdoors will be injured. Expect hail 
         damage to roofs, siding, windows, and vehicles. Expect wind 
         damage to roofs, siding, and trees.

This severe storm will be near...
  Remsen around 550 PM CDT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This storm is producing large hail. SEEK SHELTER NOW inside a sturdy
structure and stay away from windows.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Sioux Falls.

&&

LAT...LON 4265 9609 4295 9607 4295 9586 4289 9586
      4278 9585 4277 9585 4273 9586 4264 9589
      4265 9608
TIME...MOT...LOC 2247Z 201DEG 35KT 4279 9594 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...1.50 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

IG

What 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 Apr 13, 2:50 PM CDT, 2 hours 36 minutes earlier. Its key messages:

  • Thunderstorms return this afternoon and evening. Scattered strong to severe storms expected - greatest risk for southwestern Minnesota into adjacent areas of South Dakota and northwest Iowa. Timing of greatest concern is 4 to 9 PM.
  • Main hazards are large hail greater than 2 inches in diameter and wind gusts to 70 mph. A tornado or two are also possible. Have a severe weather plan and multiple ways to receive warnings.
  • Periodic chances (20-60%) for showers and thunderstorms continue this week. Details remain uncertain at this time.
Area forecast discussion, Apr 13, 2:50 PM CDT, 2 hours 36 minutes before
Area Forecast Discussion
National Weather Service Sioux Falls SD
250 PM CDT Mon Apr 13 2026

.KEY MESSAGES...

- Thunderstorms return this afternoon and evening. Scattered
  strong to severe storms expected - greatest risk for
  southwestern Minnesota into adjacent areas of South Dakota and
  northwest Iowa. Timing of greatest concern is 4 to 9 PM.

- Main hazards are large hail greater than 2 inches in diameter
  and wind gusts to 70 mph. A tornado or two are also possible.
  Have a severe weather plan and multiple ways to receive
  warnings.

- Periodic chances (20-60%) for showers and thunderstorms
  continue this week. Details remain uncertain at this time.

&&

.DISCUSSION...
Issued at 238 PM CDT Mon Apr 13 2026

Scattered thunderstorms are set to develop over the next
few hours, bringing the potential for a few severe storms with large
hail, damaging winds, and perhaps a tornado or two. As of 2 pm,
a surface low is located over northern Nebraska with a warm
front extending northeast of it across far southeastern South
Dakota into northwest Iowa. Dew points in the 60s have been
gradually spreading northward, and these higher dew points are
expected to reach the I-90 corridor over the next couple of
hours. This boundary will be the focus of initial storm
development, with these storms having access to 35-50 kts of
effective bulk shear and 1500-2000 J/kg of MLCAPE. There are
questions though on how much some high clouds have limited the
area from reaching full heating potential, but if a storm can
get going then steep mid level lapse rates of 7.5-8.5 degrees
C/km and mostly straight, elongated hodographs will favor large
hail to around 2 inches in diameter or larger. The secondary
threat will be damaging wind gusts up to 70 mph. If a storm can
get rooted to the aforementioned surface warm front, then a
tornado or two will also be possible. Can't rule out a strong
tornado either, primarily over southwest Minnesota. As the low
pressure system drift across the area, a few additional showers
and storms look to develop farther south across northwest Iowa
(down to about IA Highway-3, or just north of US Highway-20)
within the warm sector around sunset. These storms could also be
on the strong to severe side, with an isolated instance of
quarter sized hail and 60 mph as the threats.

Showers and storms will exit off to our east by the mid
evening hours, leaving mostly quiet conditions in its wake. A few
showers may develop in central South Dakota prior to daybreak
Tuesday, but dry air should win out and prevent most if not all of
this from reaching the ground. Patchy fog will also be possible
by early Tuesday morning across portions of northwest Iowa and
southwest Minnesota as winds turn light and variable overnight
and ample moisture remains in place. Temperatures tonight drop
mainly in the 40s, though some 50s are possible in our
easternmost areas. Low chances for showers continue into the day
on Tuesday, but activity is expected to remain spotty at best
as rain continues to battle a dry sub cloud layer. Highs will
range from the 60s northwest to 70s southeast. Rain chances look
to increase Tuesday night into Wednesday as two shortwave
troughs impact our area. The best chances of rain and storms
look to be over northwest Iowa and adjacent areas of Nebraska,
South Dakota, and Minnesota. At this time, severe weather looks
unlikely with this system as the better instability looks to be
off to our south and east.

Rain and storms exit off to our east by Wednesday night, leading to
a dry Thursday. Winds look to increase on Thursday especially west
of I-29 closer to a deepening surface low, and winds may take on a
southwesterly component especially in south central South Dakota.
This could lead to another day with higher fire danger as
temperatures will be warm and relative humidity values drop to 25%
or below mainly along and west of the James River. Still some
uncertainty into how breezy the winds will be, so keep up to date
with the latest forecast. Not too much time to look into the
extended forecast given the near term severe weather threat, but
guidance is in fairly good agreement that the western trough
will begin to move into our area by the end of the work
week/early weekend. This could bring more rain and storms to our
area on Friday and then colder weather into Saturday as
guidance indicates a stronger push of cold air advection behind
this system.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1241 PM CDT Mon Apr 13 2026

Isolated to widely scattered showers and storms are expected to
develop this afternoon, especially east of I-29 into southern
Minnesota and northern Iowa. Enough confidence to at least include a
PROB30 group for thunderstorms at KFSD, but it looks like storms
should stay largely east of KSUX and KHON. Storms will be capable of
large hail and damaging winds. Showers and storms will quickly push
off to our east this evening, leading to quieter conditions
overnight. Some patchy fog is possible mainly over portions of
northwest Iowa and southwest Minnesota Tuesday morning.

A frontal system will move across the area today, changing winds
from a more southerly direction to a more northerly direction as we
head into the evening hours. Winds turn mainly light and variable
overnight and stay fairly light through the end of the period.

&&

.FSD WATCHES/WARNINGS/ADVISORIES...
SD...None.
MN...None.
IA...None.
NE...None.

&&

DISCUSSION...Samet
AVIATION...Samet
Hazardous weather outlook, Apr 13, 3:56 PM CDT, 1 hour 30 minutes before
Hazardous Weather Outlook
National Weather Service Sioux Falls SD
356 PM CDT Mon Apr 13 2026

IAZ001>003-012>014-020>022-031-032-MNZ071-072-080-081-089-090-097-
098-NEZ013-014-SDZ038>040-050-052>071-142100-
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-
356 PM CDT Mon Apr 13 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.

Scattered strong to severe thunderstorms expected Monday afternoon
and evening. Some storms may produce large hail 2 inches in diameter
and damaging wind gusts up to 70 mph. A tornado or two cannot be
ruled out. Greatest risk of storms is north of I-90 between 4 and 10
PM.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

More widespread chances for showers and thunderstorms exists for
Tuesday afternoon into Wednesday. This more active pattern continues
into the weekend.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

In the hours before

Local storm report, Apr 13, 3:39 PM CDT, 1 hour 47 minutes before
Preliminary Local Storm Report
National Weather Service Sioux Falls SD
339 PM CDT Mon Apr 13 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0332 PM     Hail             Tripp                   43.23N 97.97W
04/13/2026  E0.75 Inch       Hutchinson         SD   Public

            Report from mPING: Dime (0.75 in.).

&&

TRM
Local storm report, Apr 13, 4:29 PM CDT, 57 minutes before
Preliminary Local Storm Report
National Weather Service Sioux Falls SD
429 PM CDT Mon Apr 13 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0400 PM     Hail             4 NW Olivet             43.29N 97.73W
04/13/2026  E1.00 Inch       Hutchinson         SD   Public

&&

TRM
Local storm report, Apr 13, 4:44 PM CDT, 42 minutes before
Preliminary Local Storm Report
National Weather Service Sioux Falls SD
444 PM CDT Mon Apr 13 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0416 PM     Hail             5 NNE Olivet            43.31N 97.63W
04/13/2026  M1.00 Inch       Hutchinson         SD   Public

&&

TRM
Local storm report, Apr 13, 5:23 PM CDT, 3 minutes before
Preliminary Local Storm Report
National Weather Service Sioux Falls SD
523 PM CDT Mon Apr 13 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0440 PM     Hail             3 S Freeman             43.31N 97.44W
04/13/2026  E1.25 Inch       Hutchinson         SD   Public

&&

TRM

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 13, 5:56 PM CDTSevere Thunderstorm WarningFSDCherokee, Plymouth29 min
Apr 13, 6:05 PM CDTSevere Thunderstorm WarningFSDCherokee, O'Brien, Plymouth, Sioux40 min
Apr 13, 6:30 PM CDTSevere Thunderstorm WarningFSDDickinson, Osceola45 min
Apr 13, 6:45 PM CDTSevere Thunderstorm WarningFSDO'Brien, Osceola45 min
Apr 13, 6:53 PM CDTSevere Thunderstorm WarningFSDCherokee, Clay, O'Brien52 min

Nearby

Severe Thunderstorm Warnings in Iowa, 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.