After a complex of storms moved through the state in the early morning hours of the 28th, producing a smattering of sub-severe to severe hail, the area found itself entrenched firmly within the warm sector of a low pressure system passing to the northwest.  Resulting MLCAPE values during the afternoon and early evening were in the 2000-3000 J/kg range, along with effective bulk shear around 40-50 kts, LCL heights under 1000 m, and semi-supportive 0-1 km helicity around 100 m2/s2.  With such an environment, parameters such as the sig tor (effective layer) highlighted large portions of Iowa during the afternoon and evening hours.  Resulting storms quickly went supercellular and proceeded to produce multiple tornadoes and large hail in excess of 2.5 inches throughout central and southwest Iowa. Seven tornadoes occurred across mainly rural portions of southwest into central Iowa in this event. The longest tornado was an EF1 tornado that touched down in Warren County and crossed into Marion County that was on the ground for over 17 miles. Much of the tornado  moved through rural portions of Warren and Marion Counties, but one farmstead received damage along the Warren/Marion County line with additional light damage to rural residences in Marion County. A large wedge EF2 tornado touched down in Taylor County moving through mainly rural areas. One outbuilding was nearly destroyed and minor damage was done to a house.

Funnel Cloud in WEBSTER, IOWA
From 28-JUN-17 14:20:00 to 28-JUN-17 14:20:00 (CST-6)
Location: TARA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported a funnel cloud.

Hail in DALLAS, IOWA
From 28-JUN-17 15:53:00 to 28-JUN-17 15:53:00 (CST-6)
Location: DE SOTO
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported golf ball sized hail.

Hail in BOONE, IOWA
From 28-JUN-17 02:31:00 to 28-JUN-17 02:31:00 (CST-6)
Location: LUTHER
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Emergency manager reported nickel to quarter sized hail along with estimated 40-45 mph wind gusts.

Hail in WEBSTER, IOWA
From 28-JUN-17 14:26:00 to 28-JUN-17 14:26:00 (CST-6)
Location: FT DODGE
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Public reported golf ball sized hail.

Hail in WEBSTER, IOWA
From 28-JUN-17 14:26:00 to 28-JUN-17 14:26:00 (CST-6)
Location: FT DODGE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported mostly dime sized hail, but some quarter sized mixed in.

Thunderstorm Wind in WEBSTER, IOWA
From 28-JUN-17 14:35:00 to 28-JUN-17 14:35:00 (CST-6)
Location: (FOD)FT DODGE MUNI A
Magnitude: 51.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Fort Dodge Airport ASOS recorded a 59 mph wind gust.

Tornado in TAYLOR, IOWA
From 28-JUN-17 16:05:00 to 28-JUN-17 16:33:00 (CST-6)
Location: BEDFORD ARPT
Tornado F-scale: EF2
Property damage: 75.00K
Crop damage: 10.00K
Reported by: NWS Storm Survey

Large wedge tornado moved across southern Taylor County.  The tornado remained in rural areas with primarily tree and crop damage.  A few structures were also hit with some minor damage to a house and one old outbuilding nearly destroyed.  Most intense damage  occurred in the later half of the tornado path where EF2 damage was observed as 4 large wooden electrical power line towers where destroyed along with decimating a nearby grove of trees.

Hail in POLK, IOWA
From 28-JUN-17 16:23:00 to 28-JUN-17 16:23:00 (CST-6)
Location: URBANDALE
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

NWS employee reported quarter sized hail.

Funnel Cloud in UNION, IOWA
From 28-JUN-17 16:54:00 to 28-JUN-17 16:54:00 (CST-6)
Location: LORIMOR
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported a funnel cloud.

Hail in POLK, IOWA
From 28-JUN-17 16:22:00 to 28-JUN-17 16:22:00 (CST-6)
Location: WINDSOR HGTS
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Public reported quarter sized hail.

Tornado in WARREN, IOWA
From 28-JUN-17 16:54:00 to 28-JUN-17 16:57:00 (CST-6)
Location: SANDYVILLE
Tornado F-scale: EF1
Property damage: 10.00K
Crop damage: 1.00K
Reported by: NWS Storm Survey

Tornado developed in far eastern Warren County and hit a farmstead along the county line road with Marion County, producing EF1 damage at the site.  The tornado then moved into Marion County.

Tornado in MARION, IOWA
From 28-JUN-17 16:57:00 to 28-JUN-17 17:26:00 (CST-6)
Location: PLEASANTVILLE
Tornado F-scale: EF1
Property damage: 75.00K
Crop damage: 5.00K
Reported by: NWS Storm Survey

Tornado moved into Marion County from Warren County.  The tornado remained in rural portions of the county south and east of Pleasantville with the tornado lifting just southwest of Otley.  Several rural residences received light damage with much tree damage along the path.

Tornado in WARREN, IOWA
From 28-JUN-17 17:18:00 to 28-JUN-17 17:19:00 (CST-6)
Location: NEW VIRGINIA
Tornado F-scale: EF0
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

A brief tornado developed east of New Virginia and moved through a rural field before lifting.

Funnel Cloud in UNION, IOWA
From 28-JUN-17 16:30:00 to 28-JUN-17 16:30:00 (CST-6)
Location: AFTON
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported a funnel cloud.

Hail in POLK, IOWA
From 28-JUN-17 16:30:00 to 28-JUN-17 16:30:00 (CST-6)
Location: CLOVER HILLS
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported quarter sized hail.

Thunderstorm Wind in POLK, IOWA
From 28-JUN-17 16:30:00 to 28-JUN-17 16:30:00 (CST-6)
Location: LOVINGTON
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported six inch diameter tree branches down.

Funnel Cloud in UNION, IOWA
From 28-JUN-17 16:36:00 to 28-JUN-17 16:36:00 (CST-6)
Location: LORIMOR
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported a funnel cloud.

Hail in MARSHALL, IOWA
From 28-JUN-17 16:45:00 to 28-JUN-17 16:45:00 (CST-6)
Location: MARSHALLTOWN
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported nickel sized hail.

Hail in STORY, IOWA
From 28-JUN-17 16:22:00 to 28-JUN-17 16:22:00 (CST-6)
Location: COLO
Magnitude: 2.00 
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Funnel Cloud in ADAIR, IOWA
From 28-JUN-17 15:22:00 to 28-JUN-17 15:22:00 (CST-6)
Location: FONTANELLE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported a funnel cloud.

Hail in DALLAS, IOWA
From 28-JUN-17 15:46:00 to 28-JUN-17 15:46:00 (CST-6)
Location: VAN METER
Magnitude: 2.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Media relayed public report of baseball sized hail.  This is a delayed report via social media.

Hail in BLACK HAWK, IOWA
From 28-JUN-17 18:10:00 to 28-JUN-17 18:10:00 (CST-6)
Location: LA PORTE CITY
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Public reported quarter sized hail via social media.

Hail in TAYLOR, IOWA
From 28-JUN-17 19:34:00 to 28-JUN-17 19:34:00 (CST-6)
Location: BEDFORD
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported golf ball sized hail.

Funnel Cloud in MARION, IOWA
From 28-JUN-17 18:08:00 to 28-JUN-17 18:08:00 (CST-6)
Location: PLEASANTVILLE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported a funnel cloud.

Funnel Cloud in MARION, IOWA
From 28-JUN-17 17:25:00 to 28-JUN-17 17:25:00 (CST-6)
Location: KNOXVILLE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported a funnel cloud.

Funnel Cloud in WARREN, IOWA
From 28-JUN-17 17:22:00 to 28-JUN-17 17:22:00 (CST-6)
Location: NEW VIRGINIA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported a funnel cloud.

Hail in TAMA, IOWA
From 28-JUN-17 17:07:00 to 28-JUN-17 17:07:00 (CST-6)
Location: GLADBROOK
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Media relayed report of half dollar sized hail via social media.

Hail in WARREN, IOWA
From 28-JUN-17 16:40:00 to 28-JUN-17 16:40:00 (CST-6)
Location: INDIANOLA
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in TAYLOR, IOWA
From 28-JUN-17 19:50:00 to 28-JUN-17 19:50:00 (CST-6)
Location: MERLE JCT
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported half dollar sized hail.

Hail in TAYLOR, IOWA
From 28-JUN-17 15:50:00 to 28-JUN-17 15:50:00 (CST-6)
Location: NEW MARKET
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported quarter sized hail.

Thunderstorm Wind in HARDIN, IOWA
From 28-JUN-17 17:55:00 to 28-JUN-17 17:55:00 (CST-6)
Location: IOWA FALLS MUNI ARPT
Magnitude: 50.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Iowa Falls Airport AWOS recorded a 58 mph wind gust.

Thunderstorm Wind in WARREN, IOWA
From 28-JUN-17 16:09:00 to 28-JUN-17 16:09:00 (CST-6)
Location: CUMMING
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported a tree snapped off near the Warren/Madison County line.

Hail in TAMA, IOWA
From 28-JUN-17 17:19:00 to 28-JUN-17 17:19:00 (CST-6)
Location: GLADBROOK
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Amateur radio operator reported quarter sized hail.

Hail in DALLAS, IOWA
From 28-JUN-17 16:18:00 to 28-JUN-17 16:18:00 (CST-6)
Location: HADDEN HILL
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Public reported nickel sized hail.

Tornado in ADAMS, IOWA
From 28-JUN-17 15:21:00 to 28-JUN-17 15:30:00 (CST-6)
Location: CARBON
Tornado F-scale: EF1
Property damage: 10.00K
Crop damage: 5.00K
Reported by: NWS Storm Survey

Tornado tracked across rural areas northwest of Carbon.  Some minor damage occurred to outbuildings with most of the damage occurring to trees along the path.

Tornado in ADAMS, IOWA
From 28-JUN-17 15:43:00 to 28-JUN-17 15:46:00 (CST-6)
Location: CARL
Tornado F-scale: EF0
Property damage: 1.00K
Crop damage: 2.00K
Reported by: Public

A weak tornado passed through rural areas of Adams county north of Prescott.  Very minor tree damage was observed at one rural house.  Tornado was captured on video by the public.

Hail in STORY, IOWA
From 28-JUN-17 16:09:00 to 28-JUN-17 16:09:00 (CST-6)
Location: CAMBRIDGE
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported half dollar sized hail.

Hail in DALLAS, IOWA
From 28-JUN-17 16:17:00 to 28-JUN-17 16:17:00 (CST-6)
Location: WAUKEE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Public reported quarter sized hail.

Hail in TAYLOR, IOWA
From 28-JUN-17 16:08:00 to 28-JUN-17 16:08:00 (CST-6)
Location: BEDFORD
Magnitude: 2.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Media reported baseball sized hail.

Funnel Cloud in HARDIN, IOWA
From 28-JUN-17 16:20:00 to 28-JUN-17 16:20:00 (CST-6)
Location: ALDEN
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported a funnel cloud.

Hail in POLK, IOWA
From 28-JUN-17 16:21:00 to 28-JUN-17 16:21:00 (CST-6)
Location: CLOVER HILLS
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Public reported half dollar sized hail.

Tornado in ADAIR, IOWA
From 28-JUN-17 15:45:00 to 28-JUN-17 15:56:00 (CST-6)
Location: HEBRON
Tornado F-scale: EF1
Property damage: 20.00K
Crop damage: 5.00K
Reported by: NWS Storm Survey

Tornado developed in eastern Adair County and traveled through rural areas before entering Madison County.  There was minor damage to one property and impressive tree damage along the Adair/Madison County line.

Thunderstorm Wind in ADAMS, IOWA
From 28-JUN-17 15:35:00 to 28-JUN-17 15:35:00 (CST-6)
Location: CARL
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported large limbs snapped off a tree.

Tornado in MADISON, IOWA
From 28-JUN-17 15:56:00 to 28-JUN-17 16:00:00 (CST-6)
Location: MIDDLE RIVER
Tornado F-scale: EF1
Property damage: 0.00K
Crop damage: 1.00K
Reported by: NWS Storm Survey

Tornado entered Madison County from Adair County. There was impressive tree damage just inside Madison County as the tornado moved northeast.   Little additional damage was noted for the rest of the path.

Hail in STORY, IOWA
From 28-JUN-17 16:09:00 to 28-JUN-17 16:09:00 (CST-6)
Location: CAMBRIDGE
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Law enforcement reported golf ball sized hail.

Hail in TAYLOR, IOWA
From 28-JUN-17 16:10:00 to 28-JUN-17 16:10:00 (CST-6)
Location: BEDFORD
Magnitude: 2.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported baseball sized hail.  This is a delayed report.

Funnel Cloud in TAMA, IOWA
From 28-JUN-17 19:20:00 to 28-JUN-17 19:20:00 (CST-6)
Location: ARBOR HILL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported a funnel cloud.

Tornado in ADAIR, IOWA
From 28-JUN-17 14:57:00 to 28-JUN-17 15:30:00 (CST-6)
Location: CANBY
Tornado F-scale: EF0
Property damage: 5.00K
Crop damage: 5.00K
Reported by: NWS Storm Survey

Path was intermittent for several miles after developing with condensation funnel not always visible.  However, a persistent funnel eventually formed and was well documented as it moved across northern Adair County.  It remained in rural areas with only minor damage to a few outbuildings and trees.

Hail in POLK, IOWA
From 28-JUN-17 16:00:00 to 28-JUN-17 16:00:00 (CST-6)
Location: ASHAWA
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in DALLAS, IOWA
From 28-JUN-17 16:16:00 to 28-JUN-17 16:16:00 (CST-6)
Location: WAUKEE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Amateur radio operator reported quarter sized hail.

Hail in WEBSTER, IOWA
From 28-JUN-17 14:40:00 to 28-JUN-17 14:40:00 (CST-6)
Location: FT DODGE
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported nickel sized hail.