A very unstable airmass was in place over western Iowa and areas to the west.  CAPE rose to over 6500 J/kg by late afternoon with the lifted indices falling to -12 to -15 C.  Downdraft CAPE as quite high at around 1600 J/kg, while available CAPE in the -10 to -30 C layer of the atmosphere was between 700 and 1000 J/kg.  The atmosphere had a strong shear present with 40 to 60 kts   The freezing level was quite high, just below 15,000 feet.  Precipitable water increased to around 1.5 inches.  Strong thunderstorms developed over southern Minnesota.  Initially, the thunderstorms moved east.  Once they became more rooted in the boundary layer, they moved southeast and propagated nearly due south.  The main severe threat was high winds, with numerous reports of tree, power line, and grain bin damage.  Winds of 70 MPH were measured in Estherville for example.  Seventy MPH winds were reported in Grundy County.  The outflow boundary from the complex continued to move southeast, and actually moved all the way into Missouri.  Scattered severe weather occurred with this.  Seven power poles were snapped in Polk County by the high winds.  A wind gust of 62 MPH occurred at the Ottumwa Airport.  Flash flooding also became a problem with the antecedent soil conditions nearly saturated.  Flash flooding in Emmet County resulted in the closing of Highway 4 near Wallingford and evacuations in the city.  A secondary area of thunderstorms formed over northwest Iowa and moved east-southeast into the CWA.  Heavy rains caused minor urban flooding in Calhoun County with 6 inches of standing water reported in the city of Pomeroy.  Although many of the storms produced small hail, there were very few reports of hail larger than dime size.  Reports of hail up to an inch in diameter were received in central Iowa late in the evolution of the system.  Lightning struck a house east of Grinnell during the early morning hours around 0330 CST.  The house was set on fire with structural damage and damage to contents estimated at $550,000.

Flash Flood in EMMET, IOWA
From 25-JUN-10 22:40:00 to 26-JUN-10 04:30:00 (CST-6)
Location: WELLINGFORD
Flood cause: Heavy Rain
Property damage: 150.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Residents being evacuated in town due to creek flooding.  Highway 4 also closed due to flooding.

Flash Flood in EMMET, IOWA
From 26-JUN-10 02:45:00 to 26-JUN-10 04:30:00 (CST-6)
Location: WELLINGFORD
Flood cause: Heavy Rain
Property damage: 500.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Extensive flooding along 1st, 2nd, and 3rd streets in town.  Foundation caved in with up to 4 feet of water in basements.

Flood in HUMBOLDT, IOWA
From 26-JUN-10 05:00:00 to 26-JUN-10 13:00:00 (CST-6)
Location: HUMBOLDT MUNI ARPT
Flood cause: Heavy Rain
Property damage: 300.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Many basements flooded in Humboldt.  Also bridge under water north of town on Highway 169.

Thunderstorm Wind in WORTH, IOWA
From 25-JUN-10 19:45:00 to 25-JUN-10 19:45:00 (CST-6)
Location: SILVER LAKE
Magnitude: 52.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Numerous 2 to 4 inch branches down.

Thunderstorm Wind in EMMET, IOWA
From 25-JUN-10 20:00:00 to 25-JUN-10 20:00:00 (CST-6)
Location: DOLLIVER
Magnitude: 57.00 EG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Numerous trees down in Dolliver.

Thunderstorm Wind in EMMET, IOWA
From 25-JUN-10 20:29:00 to 25-JUN-10 20:29:00 (CST-6)
Location: ESTHERVILLE
Magnitude: 61.00 MG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: ASOS

Heavy Rain in WEBSTER, IOWA
From 26-JUN-10 06:35:00 to 26-JUN-10 06:35:00 (CST-6)
Location: FT DODGE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Twenty four hour rainfall total.

Hail in WARREN, IOWA
From 26-JUN-10 07:07:00 to 26-JUN-10 07:07:00 (CST-6)
Location: INDIANOLA
Magnitude: 1.00 
Property damage: 5.00K
Crop damage: 5.00K
Reported by: Trained Spotter

Thunderstorm Wind in DALLAS, IOWA
From 25-JUN-10 23:30:00 to 25-JUN-10 23:30:00 (CST-6)
Location: DALLAS CENTER
Magnitude: 52.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

A farm wagon was blown into a pole.  Branches broken up to 6 inches in diameter by winds.

Thunderstorm Wind in GRUNDY, IOWA
From 25-JUN-10 21:31:00 to 25-JUN-10 21:31:00 (CST-6)
Location: WELLSBURG
Magnitude: 61.00 EG
Property damage: 3.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Local law enforcement reports 70 MPH wind 3 miles south of the Butler County line 6 miles east of the Hardin County line.

Thunderstorm Wind in HARDIN, IOWA
From 25-JUN-10 21:36:00 to 25-JUN-10 21:36:00 (CST-6)
Location: IOWA FALLS
Magnitude: 56.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Five inch diameter tree limbs snapped.

Thunderstorm Wind in BUTLER, IOWA
From 25-JUN-10 21:39:00 to 25-JUN-10 21:39:00 (CST-6)
Location: NEW HARTFORD
Magnitude: 52.00 EG
Property damage: 3.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Wind estimated at nearly 60 MPH.

Thunderstorm Wind in HARDIN, IOWA
From 25-JUN-10 21:45:00 to 25-JUN-10 21:45:00 (CST-6)
Location: STEAMBOAT ROCK
Magnitude: 50.00 MG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Mesonet

Thunderstorm Wind in WAPELLO, IOWA
From 26-JUN-10 00:14:00 to 26-JUN-10 00:14:00 (CST-6)
Location: (OTM)OTTUMWA INDSTRL
Magnitude: 54.00 MG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: ASOS

Flash Flood in WRIGHT, IOWA
From 25-JUN-10 23:15:00 to 26-JUN-10 03:30:00 (CST-6)
Location: HOLMES
Flood cause: Heavy Rain
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Highway 3 closed by flooding.

Lightning in POWESHIEK, IOWA
From 26-JUN-10 03:30:00 to 26-JUN-10 03:30:00 (CST-6)
Location: GRINNELL
Property damage: 550.00K
Crop damage: 0.00K
Reported by: Newspaper

Heavy Rain in CALHOUN, IOWA
From 26-JUN-10 01:24:00 to 26-JUN-10 03:30:00 (CST-6)
Location: POMEROY
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Six inches of water standing in streets.  Half inch diameter hail and wind gusts to 20 MPH.

Thunderstorm Wind in WINNEBAGO, IOWA
From 25-JUN-10 19:50:00 to 25-JUN-10 19:50:00 (CST-6)
Location: LAKE MILLS
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees down in Lake Mills.

Thunderstorm Wind in WORTH, IOWA
From 25-JUN-10 19:55:00 to 25-JUN-10 19:55:00 (CST-6)
Location: TENOLD
Magnitude: 50.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Tree down over highway 105.

Thunderstorm Wind in BUTLER, IOWA
From 25-JUN-10 21:00:00 to 25-JUN-10 21:00:00 (CST-6)
Location: AREDALE
Magnitude: 52.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Very strong wind kicking up debris.  Potential wall cloud observed.

Thunderstorm Wind in KOSSUTH, IOWA
From 25-JUN-10 21:14:00 to 25-JUN-10 21:14:00 (CST-6)
Location: ALGONA
Magnitude: 57.00 MG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Mesonet

Thunderstorm Wind in WRIGHT, IOWA
From 25-JUN-10 21:11:00 to 25-JUN-10 21:11:00 (CST-6)
Location: DOWS
Magnitude: 52.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reports wind gusts in excess of 60 MPH.  Power out in Dows.

Thunderstorm Wind in PALO ALTO, IOWA
From 25-JUN-10 21:15:00 to 25-JUN-10 21:15:00 (CST-6)
Location: GRAETTINGER
Magnitude: 54.00 EG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Several trees down in town.

Thunderstorm Wind in PALO ALTO, IOWA
From 25-JUN-10 21:25:00 to 25-JUN-10 21:25:00 (CST-6)
Location: EMMETSBURG
Magnitude: 57.00 EG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Several trees blown down.

Thunderstorm Wind in STORY, IOWA
From 25-JUN-10 22:27:00 to 25-JUN-10 22:27:00 (CST-6)
Location: NEVADA
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Two foot diameter tree down.  Power lines down on residence.

Thunderstorm Wind in EMMET, IOWA
From 25-JUN-10 20:44:00 to 25-JUN-10 20:44:00 (CST-6)
Location: WALLINGFORD
Magnitude: 61.00 EG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Grain bin down and blown into ditch.

Thunderstorm Wind in POLK, IOWA
From 25-JUN-10 23:05:00 to 25-JUN-10 23:05:00 (CST-6)
Location: ORALABOR
Magnitude: 69.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Seven power poles were blown down near the intersection of northwest 26th Street and northwest 110th by high winds.

Thunderstorm Wind in FRANKLIN, IOWA
From 25-JUN-10 21:27:00 to 25-JUN-10 21:27:00 (CST-6)
Location: OAKLAND
Magnitude: 52.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Livestock trailer blown across the road into a ditch at 45th St east of Dogwood Ave.

Thunderstorm Wind in FRANKLIN, IOWA
From 25-JUN-10 21:30:00 to 25-JUN-10 21:30:00 (CST-6)
Location: OAKLAND
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Tree damage with power outages in the area.

Thunderstorm Wind in FRANKLIN, IOWA
From 25-JUN-10 21:29:00 to 25-JUN-10 21:29:00 (CST-6)
Location: POPEJOY
Magnitude: 57.00 EG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Grain bin destroyed and laying in field along 50th Street.

Hail in STORY, IOWA
From 26-JUN-10 03:32:00 to 26-JUN-10 03:32:00 (CST-6)
Location: AMES
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 5.00K
Reported by: Trained Spotter

Heavy Rain in HUMBOLDT, IOWA
From 26-JUN-10 05:48:00 to 26-JUN-10 05:48:00 (CST-6)
Location: DAKOTA CITY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Twenty four hour rainfall total.

Heavy Rain in WRIGHT, IOWA
From 25-JUN-10 22:14:00 to 25-JUN-10 22:14:00 (CST-6)
Location: CLARION
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

The Wright County Sheriffs office reported highway 3 east and west of Clarion beginning to flood, along with county road K north of town.

Heavy Rain in EMMET, IOWA
From 25-JUN-10 22:28:00 to 25-JUN-10 23:28:00 (CST-6)
Location: WALLINGFORD
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Total rainfall just under 3 inches in the last 90 minutes.

Thunderstorm Wind in WRIGHT, IOWA
From 25-JUN-10 21:23:00 to 25-JUN-10 21:23:00 (CST-6)
Location: CLARION
Magnitude: 52.00 EG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Five evergreen trees 18 to 24 inches in diameter were uprooted.  Also 2 trees were uprooted on the northwest edge of Dows.