A warm front lifted north into Iowa during the day on the 11th.  Strong warm air advection took place along with strong moisture transport into Iowa.  Thunderstorms formed by mid-day and continued into the afternoon.  There were several reports of hail around quarter size  One storm became much stronger and produced baseball size hail in Wapello County. This storm also produced strong winds damaging a few farmsteads to the east of Ottumwa. The damage consisted of a wooden barn and carport destroyed at one farmstead, grain storage facility damage at another and additional barn damage at a third site. The storms were heavy rainfall producers with reports of around 2 inches of rain falling within a 90 minute time period with the heavier storms.  Flash flooding was reported in Clarke County.  There were also several reports of funnel clouds.

Thunderstorm Wind in WAPELLO, IOWA
From 11-MAY-14 13:31:00 to 11-MAY-14 13:31:00 (CST-6)
Location: DAHLONEGA
Magnitude: 76.00 EG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Wooden barn and carport destroyed with lots of tin spread about.

Thunderstorm Wind in WAPELLO, IOWA
From 11-MAY-14 13:37:00 to 11-MAY-14 13:37:00 (CST-6)
Location: DAHLONEGA
Magnitude: 70.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Barn damage was reported.

Hail in WAPELLO, IOWA
From 11-MAY-14 15:18:00 to 11-MAY-14 15:18:00 (CST-6)
Location: RUTLEDGE
Magnitude: 1.50 
Property damage: 4.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in WAPELLO, IOWA
From 11-MAY-14 15:30:00 to 11-MAY-14 15:30:00 (CST-6)
Location: OTTUMWA
Magnitude: 1.00 
Property damage: 3.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in WAPELLO, IOWA
From 11-MAY-14 15:20:00 to 11-MAY-14 15:20:00 (CST-6)
Location: DAHLONEGA
Magnitude: 1.00 
Property damage: 3.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Flash Flood in CLARKE, IOWA
From 11-MAY-14 11:51:00 to 11-MAY-14 14:30:00 (CST-6)
Location: OSCEOLA
Flood cause: Heavy Rain
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Highway 69 south of Osceola was closed with water over the road from White Breast Creek.

Funnel Cloud in LUCAS, IOWA
From 11-MAY-14 12:19:00 to 11-MAY-14 12:19:00 (CST-6)
Location: RUSSELL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Funnel Cloud in WAPELLO, IOWA
From 11-MAY-14 13:11:00 to 11-MAY-14 13:11:00 (CST-6)
Location: MUNTERVILLE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in CLARKE, IOWA
From 11-MAY-14 11:00:00 to 11-MAY-14 11:00:00 (CST-6)
Location: LESLIE
Magnitude: 1.00 
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Heavy Rain in CLARKE, IOWA
From 11-MAY-14 10:30:00 to 11-MAY-14 12:03:00 (CST-6)
Location: MURRAY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter measured 2.3 inches of rain.

Heavy Rain in CLARKE, IOWA
From 11-MAY-14 10:33:00 to 11-MAY-14 12:03:00 (CST-6)
Location: OSCEOLA MUNI ARPT
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Rainfall of 1.85 inches in past 90 minutes.

Heavy Rain in CLARKE, IOWA
From 11-MAY-14 11:03:00 to 11-MAY-14 12:33:00 (CST-6)
Location: WOODBURN
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Measured 2.1 inches of rain in the past 90 minutes.

Hail in WAPELLO, IOWA
From 11-MAY-14 13:29:00 to 11-MAY-14 13:29:00 (CST-6)
Location: CHILLICOTHE
Magnitude: 1.50 
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in WAPELLO, IOWA
From 11-MAY-14 15:00:00 to 11-MAY-14 15:00:00 (CST-6)
Location: BLAKESBURG
Magnitude: 2.75 
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Hail in WAPELLO, IOWA
From 11-MAY-14 15:22:00 to 11-MAY-14 15:22:00 (CST-6)
Location: OTTUMWA
Magnitude: 1.00 
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Thunderstorm Wind in CLARKE, IOWA
From 11-MAY-14 11:15:00 to 11-MAY-14 11:15:00 (CST-6)
Location: WELDON
Magnitude: 61.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Emergency Manager

A garage was destroyed and other damage was done to outbuildings.

Hail in APPANOOSE, IOWA
From 11-MAY-14 14:04:00 to 11-MAY-14 14:04:00 (CST-6)
Location: MORAVIA
Magnitude: 2.00 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Social Media

Thunderstorm Wind in CLARKE, IOWA
From 11-MAY-14 11:10:00 to 11-MAY-14 11:10:00 (CST-6)
Location: LESLIE
Magnitude: 61.00 EG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Grain bins were damaged by strong thunderstorm winds.

Thunderstorm Wind in CLARKE, IOWA
From 11-MAY-14 11:05:00 to 11-MAY-14 11:05:00 (CST-6)
Location: WELDON
Magnitude: 61.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Two to three foot diameter trees snapped at the base.

Thunderstorm Wind in WAPELLO, IOWA
From 11-MAY-14 13:30:00 to 11-MAY-14 13:30:00 (CST-6)
Location: (OTM)OTTUMWA INDSTRL
Magnitude: 74.00 EG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Grain bin damage and roof off a large bunker silo/grain storage facility with lots of tin spread about.