A high precipitation supercell initially developed to the north of Greensburg, Kansas and Pratt, Kansas, where an existing outflow boundary intersected the main synoptic cold front.  The supercells quickly dropped southeast into Barber and Harper County, Kansas. These intense supercell thunderstorms evolved into a bow echo type storm as it moved into Barber and Harper Counties, producing widespread wind damage across Harper County, Kansas.  Additional thunderstorms developed along the main cold frontal boundary across Central Kansas and produced damaging winds across portions of McPherson County near Goessel and Harvey County near Hesston and Newton.  The line of storms continued to drop southeast across much of Southern Kansas producing much needed rainfall to most of the area.

Hail in MCPHERSON, KANSAS
From 12-AUG-11 18:41:00 to 12-AUG-11 18:41:00 (CST-6)
Location: GALVA
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in MCPHERSON, KANSAS
From 12-AUG-11 18:45:00 to 12-AUG-11 18:45:00 (CST-6)
Location: GALVA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in MARION, KANSAS
From 12-AUG-11 19:11:00 to 12-AUG-11 19:11:00 (CST-6)
Location: GOESSEL
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Up to the size of nickels.

Flood in LABETTE, KANSAS
From 12-AUG-11 20:38:00 to 12-AUG-11 21:38:00 (CST-6)
Location: PARSONS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Minor street flooding was reported in the city.

Thunderstorm Wind in MARION, KANSAS
From 12-AUG-11 19:05:00 to 12-AUG-11 19:07:00 (CST-6)
Location: GOESSEL
Magnitude: 61.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Several 6 to 9 inch tree limbs were blown down and several powerlines as well.

Thunderstorm Wind in BUTLER, KANSAS
From 12-AUG-11 19:30:00 to 12-AUG-11 19:32:00 (CST-6)
Location: TOWANDA
Magnitude: 61.00 EG
Reported by: Public

A report of a railroad tie being picked up and damaging a fence. They also reported an aluminum flagpole being snapped in half and several tree limbs at least 3 inches in diameter on the ground.

Thunderstorm Wind in BUTLER, KANSAS
From 12-AUG-11 19:30:00 to 12-AUG-11 19:32:00 (CST-6)
Location: ELBING
Magnitude: 52.00 EG
Reported by: Trained Spotter

Leaves were stripped from trees and an antenna had blown off a roof.

Thunderstorm Wind in BUTLER, KANSAS
From 12-AUG-11 20:03:00 to 12-AUG-11 20:05:00 (CST-6)
Location: TOWANDA
Magnitude: 61.00 EG
Reported by: Emergency Manager

Powerlines were blown down.

Thunderstorm Wind in HARVEY, KANSAS
From 12-AUG-11 19:35:00 to 12-AUG-11 19:37:00 (CST-6)
Location: ANNELLY
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Significant tree damage was reported due to strong winds.

Thunderstorm Wind in HARPER, KANSAS
From 12-AUG-11 18:00:00 to 12-AUG-11 18:25:00 (CST-6)
Location: ATTICA
Magnitude: 74.00 EG
Reported by: Trained Spotter

Widespread tree damage was noted to the county from the storms that moved across.

Thunderstorm Wind in MCPHERSON, KANSAS
From 12-AUG-11 18:45:00 to 12-AUG-11 18:48:00 (CST-6)
Location: GALVA
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Widespread tree damage and a few downed powerlines were noted as the storms moved through.

Thunderstorm Wind in SUMNER, KANSAS
From 12-AUG-11 18:50:00 to 12-AUG-11 18:53:00 (CST-6)
Location: MILAN
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Estimated using a handheld anemometer.

Thunderstorm Wind in HARVEY, KANSAS
From 12-AUG-11 19:17:00 to 12-AUG-11 19:22:00 (CST-6)
Location: NORTH NEWTON
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Some tree limbs were blown out of trees.

Thunderstorm Wind in BUTLER, KANSAS
From 12-AUG-11 19:29:00 to 12-AUG-11 19:55:00 (CST-6)
Location: ELBING
Magnitude: 65.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Since this is a pretty remote area, only minor damage to trees were noted.

Thunderstorm Wind in MARION, KANSAS
From 12-AUG-11 19:30:00 to 12-AUG-11 19:32:00 (CST-6)
Location: BURNS
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Minor damage to trees.

Thunderstorm Wind in BUTLER, KANSAS
From 12-AUG-11 20:16:00 to 12-AUG-11 20:19:00 (CST-6)
Location: LEON
Magnitude: 56.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Minor damage to trees.

Thunderstorm Wind in LABETTE, KANSAS
From 12-AUG-11 20:24:00 to 12-AUG-11 20:25:00 (CST-6)
Location: PARSONS
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Estimated wind gust.

Thunderstorm Wind in SEDGWICK, KANSAS
From 12-AUG-11 19:50:00 to 12-AUG-11 19:52:00 (CST-6)
Location: (AAO) JABARA ARPT
Magnitude: 50.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Thunderstorm Wind in MCPHERSON, KANSAS
From 12-AUG-11 19:10:00 to 12-AUG-11 19:13:00 (CST-6)
Location: MOUNDRIDGE
Magnitude: 56.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Large tree branch was blown out of a tree.