Alert archive / Iowa / Severe Thunderstorm Warnings in 2025

Severe Thunderstorm Warning 191, NWS Des Moines, IA

July 30, 2025Black Hawk County, Grundy County, Tama County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Jul 30, 2025, 1:07 AM CDT for Black Hawk County, Grundy County, Tama County, Iowa. It was in force for 53 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 30, 2025, 1:07 AM CDT (06:07 UTC)
Expired: Jul 30, 2025, 2:00 AM CDT
In force: 53 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Black Hawk County, IA, Grundy County, IA, Tama County, IA

The radar

The Des Moines radar (KDMX), 117 km from the middle of the area, began a volume at 06:09 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.

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 6.1 hours before the alert went out and 336 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: 5070 J/kg
Mixed-layer CIN: -19 J/kg
Mixed-layer LCL: 1351 m above ground
0-6 km bulk shear: 9 kt
0-1 km storm-relative helicity: 10 m²/s²
0-3 km storm-relative helicity: 74 m²/s²
Significant tornado parameter: 1.4
Supercell composite: 14.2

Open this sounding in Storm Lab

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 Des Moines, IA wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 30, 12:43 AM CDT, 24 minutes earlier.

Area forecast discussion, Jul 30, 12:43 AM CDT, 24 minutes before

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Hazardous weather outlook, Jul 29, 5:10 PM CDT, 7 hours 57 minutes before

Hazardous Weather Outlook
National Weather Service Des Moines IA
510 PM CDT Tue Jul 29 2025

IAZ006-007-016-017-025>028-036>039-048>050-302215-
Winnebago-Worth-Hancock-Cerro Gordo-Wright-Franklin-Butler-Bremer-
Hamilton-Hardin-Grundy-Black Hawk-Story-Marshall-Tama-
510 PM CDT Tue Jul 29 2025

This Hazardous Weather Outlook is for portions of central Iowa.

.DAY ONE...Tonight

Thunderstorms are expected this evening into Wednesday morning,
with severe storms possible. Damaging winds and heavy rainfall
are the main concerns with this activity.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Showers and thunderstorms are expected to continue through the
morning Wednesday, Isolated strong storms are possible, with
gusty winds and heavy rainfall the main threats.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed this evening and at times
Wednesday.

IAZ057>062-070>075-081>086-092>097-302215-
Audubon-Guthrie-Dallas-Polk-Jasper-Poweshiek-Cass-Adair-Madison-
Warren-Marion-Mahaska-Adams-Union-Clarke-Lucas-Monroe-Wapello-
Taylor-Ringgold-Decatur-Wayne-Appanoose-Davis-
510 PM CDT Tue Jul 29 2025

This Hazardous Weather Outlook is for portions of central Iowa.

.DAY ONE...Tonight

A Heat Advisory is in effect through this evening. A Flood Watch
is in effect through early Wednesday morning. Please refer to the
National Weather Service website at weather.gov/desmoines for
further details.

Thunderstorms are expected this evening into Wednesday morning,
with severe storms possible, especially over southwestern Iowa.
Damaging winds and heavy rainfall are the main concerns with this
activity.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Showers and thunderstorms are expected to continue through the
morning Wednesday, with redevelopment possible over
southern/eastern Iowa by the afternoon to evening. A few isolated
severe storms are possible, with gusty winds and heavy rainfall
the main threats.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed this evening and at times
Wednesday.

IAZ004-005-015-023-024-033>035-044>047-302215-
Emmet-Kossuth-Palo Alto-Pocahontas-Humboldt-Sac-Calhoun-Webster-
Crawford-Carroll-Greene-Boone-
510 PM CDT Tue Jul 29 2025

This Hazardous Weather Outlook is for portions of central Iowa.

.DAY ONE...Tonight

A Flood Watch is in effect through early Wednesday morning.
Please refer to the National Weather Service website at
weather.gov/desmoines for further details.

Thunderstorms are expected this evening into Wednesday morning,
with severe storms possible, mainly over central Iowa. Damaging
winds and heavy rainfall are the main concerns with this activity.

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Showers and thunderstorms are expected to continue through the
morning Wednesday. Isolated strong storms are possible, with
gusty winds and heavy rainfall the main threats.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed this evening and at times
Wednesday.

In the hours before

Special weather statement, Jul 29, 9:16 PM CDT, 3 hours 51 minutes before

Special Weather Statement
National Weather Service Des Moines IA
916 PM CDT Tue Jul 29 2025

IAZ006-007-300300-
Winnebago IA-Worth IA-
916 PM CDT Tue Jul 29 2025

...A STRONG THUNDERSTORM WILL IMPACT WORTH AND NORTHEASTERN WINNEBAGO
COUNTIES THROUGH 1000 PM CDT...

At 916 PM CDT, Doppler radar was tracking a strong thunderstorm near
Rice Lake, or 11 miles west of Northwood, moving east at 40 mph.

HAZARD...Wind gusts up to 40 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Northwood, Lake Mills, Manly, Emmons, Rice Lake, Kensett, Grafton,
Hanlontown, Joice, Scarville, Bolan, Lake Mills Municipal Airport,
Hogsback Wildlife Area, Northwood Municipal, and Rice Lake State
Park.

This includes Interstate 35 between mile markers 204 and 218.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Persons in campgrounds should consider seeking sturdy shelter until
this storm passes.

&&

LAT...LON 4326 9302 4325 9320 4332 9360 4350 9362
      4350 9303
TIME...MOT...LOC 0216Z 273DEG 33KT 4339 9344

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH

Fowle

Special weather statement, Jul 29, 10:24 PM CDT, 2 hours 43 minutes before

Special Weather Statement
National Weather Service Des Moines IA
1024 PM CDT Tue Jul 29 2025

IAZ047-048-059-060-300400-
Boone IA-Story IA-Polk IA-Dallas IA-
1024 PM CDT Tue Jul 29 2025

...A STRONG THUNDERSTORM WILL IMPACT NORTHWESTERN POLK...SOUTHWESTERN
STORY...SOUTHEASTERN BOONE AND EASTERN DALLAS COUNTIES THROUGH 1100
PM CDT...

At 1024 PM CDT, Doppler radar was tracking a strong thunderstorm near
Woodward, or 8 miles east of Perry, moving northeast at 25 mph.

HAZARD...Wind gusts up to 50 mph and pea size hail and additional
         heavy rainfall of one to two inches.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible. Ponding of water on roadways, low visibilities,
         and rises in small streams and creeks.

Locations impacted include...
Ankeny, Urbandale, Johnston, Clive, Waukee, Boone, Grimes, Perry,
Adel, Bondurant, Polk City, Saylorville, Madrid, Dallas Center,
Slater, Granger, Woodward, Saylorville Lake, Big Creek Lake, and
Boone Speedway.

This includes the following highways...
 Interstate 35 between mile markers 89 and 97.
 Interstate 80 between mile markers 127 and 133.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 4158 9401 4183 9420 4208 9381 4168 9347
TIME...MOT...LOC 0324Z 236DEG 23KT 4180 9393

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH

Fowle

Local storm report, Jul 30, 1:04 AM CDT, 3 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 29, 8:42 PM CDT	River Flood Warning	DMX	Black Hawk	5 days
Jul 29, 8:45 PM CDT	River Flood Watch	DMX	Poweshiek, Tama	14 hr
Jul 29, 8:45 PM CDT	River Flood Watch	DMX	Black Hawk	3 days
Jul 29, 8:45 PM CDT	River Flood Watch	DMX	Marshall	4 days
Jul 29, 8:45 PM CDT	River Flood Watch	DMX	Black Hawk	38 hr
Jul 29, 8:46 PM CDT	River Flood Watch	DMX	Cerro Gordo, Floyd, Worth	7 hr
Jul 29, 9:16 PM CDT	Special Weather Statement	DMX	Worth	44 min
Jul 29, 9:46 PM CDT	River Flood Watch	DMX	Polk	12 hr
Jul 29, 10:24 PM CDT	Special Weather Statement	DMX	Dallas, Polk	36 min
Jul 30, 12:13 AM CDT	Severe Thunderstorm Warning	DMX	Grundy, Marshall, Tama	47 min
Jul 30, 12:45 AM CDT	Severe Thunderstorm Warning	DMX	Audubon, Carroll, Crawford, Greene, Guthrie	45 min
Jul 30, 1:16 AM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Carroll, Dallas, Greene, Guthrie, Webster	44 min
Jul 30, 1:25 AM CDT	Severe Thunderstorm Warning	DMX	Adair, Audubon, Cass, Dallas, Guthrie	46 min
Jul 30, 1:46 AM CDT	Severe Thunderstorm Warning	DMX	Boone, Dallas, Greene, Guthrie, Hamilton, Polk and 1 more	59 min
Jul 30, 2:47 AM CDT	Severe Thunderstorm Warning	DMX	Boone, Dallas, Polk, Story	43 min
Jul 30, 3:59 AM CDT	River Flood Warning	DMX	Cerro Gordo, Floyd, Worth	3 days
Jul 30, 10:12 AM CDT	River Flood Warning	DMX	Polk	5 days
Jul 30, 10:21 AM CDT	River Flood Watch	DMX	Hamilton, Humboldt, Webster	4 days
Jul 30, 10:21 AM CDT	River Flood Watch	DMX	Humboldt	69 hr
Jul 30, 10:21 AM CDT	River Flood Watch	DMX	Humboldt, Kossuth	25 hr
Jul 30, 10:26 AM CDT	River Flood Watch	DMX	Dallas	20 hr
Jul 30, 10:39 AM CDT	River Flood Warning	DMX	Poweshiek, Tama	4 days
Jul 30, 11:28 AM CDT	River Flood Watch	DMX	Franklin, Wright	62 hr
Jul 30, 1:26 PM CDT	River Flood Warning	DMX	Marion, Polk, Warren	5 days

Nearby

Severe Thunderstorm Warnings in Iowa, 2025 Every severe thunderstorm warning in 2025

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.