Alert archive / Iowa / Tornado Warnings in 2026

Tornado Warning 13, NWS Des Moines, IA

April 17, 2026Mahaska County, Marion County, Monroe County, Iowa

NWS Des Moines, IA issued this tornado warning at Apr 17, 2026, 3:16 PM CDT for Mahaska County, Marion County, Monroe County, Iowa. It was in force for 29 min. 1 report 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 17, 2026, 3:16 PM CDT (20:16 UTC)
Expired: Apr 17, 2026, 3:45 PM CDT
In force: 29 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Tornado: Observed
Hail: 1.0 in

Counties Mahaska County, IA, Marion County, IA, Monroe County, IA

The radar

The Des Moines radar (KDMX), 89 km from the middle of the area, began a volume at 20:19 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
Apr 17, 3:23 PM CDT	HAIL 1	Bussey, IA

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
Apr 17, 12:40 PM CDT	Tornado Watch	SPC	9 hr

The nearest sounding before it

Topeka, KS (KTOP), launched 12:00Z, 8.3 hours before the alert went out and 343 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 2338 J/kg
Mixed-layer CIN: -172 J/kg
Mixed-layer LCL: 934 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 379 m²/s²
0-3 km storm-relative helicity: 354 m²/s²
Significant tornado parameter: 0.8
Supercell composite: 16.5

Open this sounding in Storm Lab

The text

As transmitted.

791 
WFUS53 KDMX 172016
TORDMX
IAC123-125-135-172045-
/O.NEW.KDMX.TO.W.0013.260417T2016Z-260417T2045Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Des Moines IA
316 PM CDT Fri Apr 17 2026

The National Weather Service in Des Moines has issued a

* Tornado Warning for...
  Northwestern Monroe County in south central Iowa...
  Southeastern Marion County in south central Iowa...
  Northwestern Mahaska County in south central Iowa...

* Until 345 PM CDT.

* At 316 PM CDT, a confirmed tornado was located over Marysville, or
  11 miles southeast of Knoxville, moving northeast at 55 mph.

  HAZARD...Damaging tornado and quarter size hail.

  SOURCE...Weather spotters confirmed tornado.

  IMPACT...Flying debris will be dangerous to those caught without 
           shelter. Mobile homes will be damaged or destroyed. 
           Damage to roofs, windows, and vehicles will occur.  Tree 
           damage is likely.

* The tornado will be near...
  Bussey, Hamilton, and Marysville around 320 PM CDT.
  Leighton around 330 PM CDT.

Other locations impacted by this tornadic thunderstorm include
Marysville, Bussey, Hamilton, Harvey, Beacon, Leighton, and
University Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

To repeat, a tornado is on the ground. TAKE COVER NOW! Move to a
basement or an interior room on the lowest floor of a sturdy
building. Avoid windows. If you are outdoors, in a mobile home, or in
a vehicle, move to the closest substantial shelter and protect
yourself from flying debris.

&&

LAT...LON 4110 9300 4116 9310 4150 9276 4134 9251
TIME...MOT...LOC 2016Z 225DEG 46KT 4118 9298 

TORNADO...OBSERVED
MAX HAIL SIZE...1.00 IN

$$

Ansorge

3 follow-up statements

729 
WWUS53 KDMX 172019
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
319 PM CDT Fri Apr 17 2026

IAC135-172029-
/O.CAN.KDMX.TO.W.0013.000000T0000Z-260417T2045Z/
Monroe IA-
319 PM CDT Fri Apr 17 2026

...THE TORNADO WARNING FOR NORTHWESTERN MONROE COUNTY IS CANCELLED...

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

A Tornado Watch remains in effect until 800 PM CDT for south central
Iowa.

LAT...LON 4116 9293 4116 9306 4150 9276 4134 9251
TIME...MOT...LOC 2019Z 225DEG 36KT 4120 9295 

$$

IAC123-125-172045-
/O.CON.KDMX.TO.W.0013.000000T0000Z-260417T2045Z/
Marion IA-Mahaska IA-
319 PM CDT Fri Apr 17 2026

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 345 PM CDT FOR
SOUTHEASTERN MARION AND NORTHWESTERN MAHASKA COUNTIES...

At 319 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Marysville, or 11 miles southeast of Knoxville,
moving northeast at 40 mph.

HAZARD...Tornado and quarter size hail.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This dangerous storm will be near...
  Bussey around 325 PM CDT.
  Leighton around 330 PM CDT.

Other locations impacted by this tornadic thunderstorm include
Marysville, Beacon, Bussey, Leighton, Hamilton, and Harvey.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4116 9293 4116 9306 4150 9276 4134 9251
TIME...MOT...LOC 2019Z 225DEG 36KT 4120 9295 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...1.00 IN

$$

Ansorge

510 
WWUS53 KDMX 172031
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
331 PM CDT Fri Apr 17 2026

IAC123-125-172045-
/O.CON.KDMX.TO.W.0013.000000T0000Z-260417T2045Z/
Marion IA-Mahaska IA-
331 PM CDT Fri Apr 17 2026

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 345 PM CDT FOR EAST
CENTRAL MARION AND NORTHWESTERN MAHASKA COUNTIES...

At 331 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Leighton, or 7 miles southeast of Pella, moving
northeast at 50 mph.

HAZARD...Tornado and quarter size hail.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This dangerous storm will be near...
  Leighton around 335 PM CDT.

Other locations impacted by this tornadic thunderstorm include Harvey
and Leighton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4124 9285 4130 9294 4150 9276 4139 9260
TIME...MOT...LOC 2031Z 222DEG 46KT 4132 9284 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...1.00 IN

$$

Ansorge

045 
WWUS53 KDMX 172036
SVSDMX

Severe Weather Statement
National Weather Service Des Moines IA
336 PM CDT Fri Apr 17 2026

IAC125-172046-
/O.CAN.KDMX.TO.W.0013.000000T0000Z-260417T2045Z/
Marion IA-
336 PM CDT Fri Apr 17 2026

...THE TORNADO WARNING FOR EAST CENTRAL MARION COUNTY IS CANCELLED...

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

A Tornado Watch remains in effect until 800 PM CDT for south central
Iowa.

LAT...LON 4128 9280 4138 9287 4150 9276 4139 9260
TIME...MOT...LOC 2036Z 225DEG 46KT 4137 9277 

$$

IAC123-172045-
/O.CON.KDMX.TO.W.0013.000000T0000Z-260417T2045Z/
Mahaska IA-
336 PM CDT Fri Apr 17 2026

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 345 PM CDT FOR
NORTHWESTERN MAHASKA COUNTY...

At 336 PM CDT, a severe thunderstorm capable of producing a tornado
was located over Leighton, or 7 miles east of Pella, moving northeast
at 55 mph.

HAZARD...Tornado and quarter size hail.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without 
         shelter. Mobile homes will be damaged or destroyed. Damage 
         to roofs, windows, and vehicles will occur.  Tree damage is 
         likely.

This tornadic thunderstorm will remain over mainly rural areas of
northwestern Mahaska County, including the following locations...
Leighton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TAKE COVER NOW! Move to a basement or an interior room on the lowest
floor of a sturdy building. Avoid windows. If you are outdoors, in a
mobile home, or in a vehicle, move to the closest substantial shelter
and protect yourself from flying debris.

&&

LAT...LON 4128 9280 4138 9287 4150 9276 4139 9260
TIME...MOT...LOC 2036Z 225DEG 46KT 4137 9277 

TORNADO...RADAR INDICATED
MAX HAIL SIZE...1.00 IN

$$

Ansorge

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 17, 1:52 PM CDT	Severe Thunderstorm Warning	DMX	Ringgold, Taylor	38 min
Apr 17, 1:57 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Marshall, Polk, Story	48 min
Apr 17, 2:01 PM CDT	Severe Thunderstorm Warning	DMX	Dallas, Madison, Polk, Warren	29 min
Apr 17, 2:11 PM CDT	Severe Thunderstorm Warning	DMX	Bremer, Butler, Franklin, Grundy, Hardin	34 min
Apr 17, 2:25 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Mahaska, Marion, Poweshiek	50 min
Apr 17, 2:29 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Marshall, Poweshiek, Story, Tama	46 min
Apr 17, 2:33 PM CDT	Tornado Warning	DMX	Jasper, Marshall, Poweshiek, Tama	42 min
Apr 17, 2:35 PM CDT	Severe Thunderstorm Warning Considerable damage threat	DMX	Bremer, Butler	40 min
Apr 17, 2:38 PM CDT	Tornado Warning	DMX	Black Hawk, Bremer, Butler	30 min
Apr 17, 2:44 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Marshall, Poweshiek	31 min
Apr 17, 2:47 PM CDT	Severe Thunderstorm Warning	DMX	Appanoose, Lucas, Mahaska, Marion, Monroe, Wayne	43 min
Apr 17, 2:57 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Lucas, Marion, Warren	11 min
Apr 17, 2:59 PM CDT	Severe Thunderstorm Warning	DMX	Decatur, Ringgold, Wayne	46 min
Apr 17, 3:03 PM CDT	Tornado Warning	DMX	Lucas, Marion, Monroe	11 min
Apr 17, 3:07 PM CDT	Severe Thunderstorm Warning	DMX	Marshall, Tama	38 min
Apr 17, 3:10 PM CDT	Severe Thunderstorm Warning	DMX	Mahaska, Marion, Poweshiek	50 min
Apr 17, 3:13 PM CDT	Severe Thunderstorm Warning	DMX	Appanoose, Monroe, Wayne	17 min
Apr 17, 3:15 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Poweshiek	45 min
Apr 17, 3:16 PM CDT	Tornado Warning	DMX	Tama	29 min
Apr 17, 3:24 PM CDT	Tornado Warning	DMX	Poweshiek	39 min
Apr 17, 3:26 PM CDT	Severe Thunderstorm Warning	DMX	Mahaska, Monroe, Wapello	64 min
Apr 17, 3:28 PM CDT	Severe Thunderstorm Warning	DMX	Appanoose, Wayne	47 min
Apr 17, 3:44 PM CDT	Severe Thunderstorm Warning Considerable damage threat	DMX	Poweshiek, Tama	31 min
Apr 17, 4:01 PM CDT	Severe Thunderstorm Warning	DMX	Appanoose, Davis, Monroe, Wapello	44 min
Apr 17, 4:02 PM CDT	Severe Thunderstorm Warning	DMX	Poweshiek, Tama	15 min
Apr 17, 4:13 PM CDT	Severe Thunderstorm Warning	DMX	Appanoose, Monroe, Wayne	32 min
Apr 17, 4:17 PM CDT	Tornado Warning	DMX	Davis, Wapello	28 min
Apr 17, 4:26 PM CDT	Severe Thunderstorm Warning	DMX	Wapello	19 min
Apr 17, 4:30 PM CDT	Tornado Warning	DMX	Davis, Wapello	30 min
Apr 17, 6:16 PM CDT	Special Weather Statement	DMX	Polk	29 min

Nearby

Tornado Warnings in Iowa, 2026 Every tornado warning in 2026 Tornadoes 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.