Storms developed ahead of a strong cold front as it moved through the region.  There were numerous reports of damaging winds as well as some isolated large hail and flash flooding.

Thunderstorm Wind in RALLS, MISSOURI
From 27-JUN-10 17:08:00 to 27-JUN-10 17:08:00 (CST-6)
Location: FLINTHILL
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm winds blew down several large tree limbs.

Thunderstorm Wind in ST. CHARLES, MISSOURI
From 27-JUN-10 18:02:00 to 27-JUN-10 18:02:00 (CST-6)
Location: ORCHARD FARM
Magnitude: 51.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Thunderstorm Wind in FRANKLIN, MISSOURI
From 27-JUN-10 18:07:00 to 27-JUN-10 18:07:00 (CST-6)
Location: UNION
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

Thunderstorm winds blew down a very large tree in Union City Park.  The tree crushed the playground equipment at the park.  No injuries were reported.

Thunderstorm Wind in MARION, MISSOURI
From 27-JUN-10 17:15:00 to 27-JUN-10 17:15:00 (CST-6)
Location: PALMYRA
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

Thunderstorm winds blew down a large tree limb in town.  It fell onto two cars causing minor damage.  The nearby house also sustained minor damage.

Thunderstorm Wind in OSAGE, MISSOURI
From 27-JUN-10 17:20:00 to 27-JUN-10 17:30:00 (CST-6)
Location: SHUBERT
Magnitude: 83.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

National Weather Service personnel conducted a damage survey over parts of west central Osage county and determined that the tree and structural damage was due to a combination of damaging downburst winds and microbursts from a severe thunderstorm which moved through the area between 620 pm and 630 pm.
The damage area started a quarter of a mile west of County Road 608 near the Maries River.  The roof of one machine shed was uplifted to the southeast on a farmstead near County Road 608.  Tree damage was confined at three locations along the Maries River.  One area of tree damage extended from the river up to the ridge axis across the river.  Several large oak and pecan trees were damaged in this area.
Other nearby tree damage due to the downbursts occurred along Brush Creek Hollow about 2 miles south southwest of Loose Creek.  Several large oak trees over 100 years old were uprooted due to an intense microburst.  Surface wind gusts were estimated between 85 and 95 mph in this location.
Further east, towards the south end of County Road 603, near Brush Creek, a second machine shed was completely destroyed with the debris from the shed laid to the west southwest.  As the machine shed started to lift to the west, five occupants moved inside a large pickup truck within the machine shed.  None of the occupants were injured.  A nearby house, approximately 50 yards to the south, was not damaged.  Approximately 100 to 150 yards northeast and east of the machine shed, several large hardwood trees were uprooted and also lying to the west and southwest.  This is an interesting area in which the tree and machine shed damage laid to the west and southwest and occurred immediately on the back side (west side) of the severe thunderstorm. This is an uncommon type of damage pattern.  Surface winds were estimated between 70 and 90 mph in this location.
The final area of tree damage occurred 2.2 miles southeast of the town of Loose Creek, along County Road 602.  This road was along a ridge axis and several very large oak trees were uprooted to the northeast.
The total tree and structural damage area extended 5 miles in length and one mile in width.

Thunderstorm Wind in AUDRAIN, MISSOURI
From 27-JUN-10 16:30:00 to 27-JUN-10 16:31:00 (CST-6)
Location: MEXICO
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm winds blew down a large tree across Audrain Road just south of intersection with Highway FF.  Also, large tree limbs were blown down onto Mars Street and a large tree was blown down across Osage Street.

Thunderstorm Wind in GASCONADE, MISSOURI
From 27-JUN-10 17:35:00 to 27-JUN-10 17:40:00 (CST-6)
Location: HERMANN
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Newspaper

Thunderstorm winds caused extensive tree damage in Hermann. Several large trees were blown down around town, as well as numerous branches.  One tree fell onto the pavilion at the city park damaging it and a large tree limb fell onto the wooden bandstand in the park as well, causing minor damage.

Hail in BOONE, MISSOURI
From 27-JUN-10 15:53:00 to 27-JUN-10 15:53:00 (CST-6)
Location: STURGEON
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter