A warm front lifted northeast across Iowa during the day on the 7th as a cold front approached from the northwest. The cold front reached northwest Iowa by the early morning hours of the 8th, however a shortwave lifted northeast across the state during the afternoon and evening of the 7th.  The airmass became very unstable by the mid and late afternoon hours as temperatures warmed to the upper 80s to mid 90s and dewpoint temperatures warmed to the upper 60s to mid 70s.  CAPE values rose to between 4000 and 6500 J/kg by late afternoon, and lifted indices fell to between -7 and -10 C.  The environment was moderately sheared with 25 to 35 kts of shear available.  The downdraft CAPE was quite high, and was between 800 and 1300 J/kg.  A decent amount of CAPE was available, 300 to 500 J/kg, in the -10 to -30 C. layer of the atmosphere, however the freezing level was very high.  Freezing levels ranged from 14,500 feet over northern Iowa to 16,000 feet over the south.  With the high freezing level, there was a very deep warm cloud layer with precipitable water values in the 1.6 to 1.8 inch range.  The threat for tornadoes with this system was minimal with LCL values around 1500 meters at the beginning of the event, and 2500 meters by early evening.  Thunderstorms developed over north central into west central Iowa by the mid afternoon.  Very heavy rain fell in north central Iowa where the storms intersected the warm front.  Upwards of 4 inches fell in a 2 hour period, however no flooding was reported.  As the event unfolded it became a high wind event.  The downdraft CAPE was able to be realized with numerous gusts in the 60 to 70 MPH range.  There were numerous reports of tree branches broken and several whole trees toppled.  Winds of 70 MPH hit the Waterloo-Cedar Falls area.  Tree and power line damage was extensive in the area.  High winds in Boone County overturned a semi-tractor trailer.  No injuries were reported however.  Heavy rainfall became a problem, especially after sunset when the line of thunderstorms became stationary over southern Iowa.  The heavy rain over the northern part of the state, such as the 2.44 inches that fell in Clarksville in Butler County, did not cause much in the way of flooding.  Overnight, a large area of thunderstorms remained over the same areas of south central Iowa.  Numerous reports of rain in the 4 to 6 inch range were received in the area with the heaviest rain occurring in the Appanoose and Davis County areas.  The schoolnet site in Bloomfield reported 7.68 inches of rain, while the Centerville Schoolnet site reported 7.58 inches.  A measured rainfall of 6.9 inches was received from southwest of the Bloomfield area for one of the heavier non-automated totals.  Centerville received 6.13 inches from overnight rains as reported by the Cooperative Observer.  Appanoose County had received heavy rainfall the day before, as did many of the surrounding areas.  The heavy rainfall caused water to flow over may roads and even over a few state highways.  Iowa Highway 5 was closed north of Marysville by high water for example.  Water also covered U.S. Highway 34 near Albia.

Thunderstorm Wind in WORTH, IOWA
From 07-JUL-08 13:00:00 to 07-JUL-08 13:00:00 (CST-6)
Location: MANLY
Magnitude: 52.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Several 5 to 8 inch diameter tree limbs down.

Thunderstorm Wind in WORTH, IOWA
From 07-JUL-08 12:55:00 to 07-JUL-08 12:55:00 (CST-6)
Location: DEER CREEK
Magnitude: 52.00 EG
Property damage: 3.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Flash Flood in DAVIS, IOWA
From 08-JUL-08 02:20:00 to 08-JUL-08 06:15:00 (CST-6)
Location: STEUBEN
Flood cause: Heavy Rain
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Water from the Fox River covered parts of County road J40.

Flash Flood in APPANOOSE, IOWA
From 08-JUL-08 00:00:00 to 08-JUL-08 06:15:00 (CST-6)
Location: SHARON
Flood cause: Heavy Rain
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Water was over Highway 2 at two locations...one to two miles west of the intersection with County Road T61.

Heavy Rain in BUTLER, IOWA
From 07-JUL-08 15:20:00 to 07-JUL-08 16:50:00 (CST-6)
Location: CLARKSVILLE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Rainfall in the past hour and one half was 2.44 inches.

Heavy Rain in DAVIS, IOWA
From 07-JUL-08 23:00:00 to 08-JUL-08 06:00:00 (CST-6)
Location: BLOOMFIELD
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Rainfall from the overnight storms was 6.9 inches.

Heavy Rain in APPANOOSE, IOWA
From 07-JUL-08 23:00:00 to 08-JUL-08 06:00:00 (CST-6)
Location: CENTERVILLE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

Rainfall from the overnight storms was 6.13 inches.

Flash Flood in APPANOOSE, IOWA
From 07-JUL-08 23:35:00 to 08-JUL-08 06:15:00 (CST-6)
Location: CENTERVILLE
Flood cause: Heavy Rain
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Water was reported over Highway 2.

Flash Flood in DAVIS, IOWA
From 08-JUL-08 02:00:00 to 08-JUL-08 06:15:00 (CST-6)
Location: BLOOMFIELD
Flood cause: Heavy Rain
Property damage: 75.00K
Crop damage: 0.00K
Reported by: Law Enforcement

One to three feet of water covered the streets.

Flash Flood in MARION, IOWA
From 08-JUL-08 01:00:00 to 08-JUL-08 06:00:00 (CST-6)
Location: MELCHER
Flood cause: Heavy Rain
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Water was over County road S45.

Flash Flood in MARION, IOWA
From 08-JUL-08 00:40:00 to 08-JUL-08 06:00:00 (CST-6)
Location: ATTICA
Flood cause: Heavy Rain
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Water was over the road at the intersection of 140th Ave and Vermont.

Flash Flood in MONROE, IOWA
From 08-JUL-08 01:00:00 to 08-JUL-08 06:00:00 (CST-6)
Location: AVERY
Flood cause: Heavy Rain
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Water from nearby creek was covering old Highway 34.

Thunderstorm Wind in BLACK HAWK, IOWA
From 07-JUL-08 18:12:00 to 07-JUL-08 18:12:00 (CST-6)
Location: CEDAR FALLS
Magnitude: 57.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: County Official

Numerous trees were downed by high winds in the town of Cedar Falls.

Thunderstorm Wind in BLACK HAWK, IOWA
From 07-JUL-08 18:00:00 to 07-JUL-08 18:00:00 (CST-6)
Location: (ALO)WATERLOO MUNI A
Magnitude: 59.00 MG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: ASOS

Thunderstorm Wind in BOONE, IOWA
From 07-JUL-08 16:15:00 to 07-JUL-08 16:15:00 (CST-6)
Location: PILOT MOUND
Magnitude: 52.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Four to five inch diameter tree branches downed.

Thunderstorm Wind in BREMER, IOWA
From 07-JUL-08 16:42:00 to 07-JUL-08 16:42:00 (CST-6)
Location: PLAINFIELD
Magnitude: 52.00 EG
Property damage: 3.00K
Crop damage: 0.00K
Reported by: NWS Employee

Numerous tree branches down with 0.92 inches of rain in the past 10 minutes.

Thunderstorm Wind in BREMER, IOWA
From 07-JUL-08 16:44:00 to 07-JUL-08 16:59:00 (CST-6)
Location: WAVERLY
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Whole trees in motion with intermittent strong gusts for the past 15 minutes.

Thunderstorm Wind in BUTLER, IOWA
From 07-JUL-08 17:00:00 to 07-JUL-08 17:00:00 (CST-6)
Location: SHELL ROCK
Magnitude: 52.00 EG
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Tree damage with one falling on the roof of a house.

Thunderstorm Wind in BUTLER, IOWA
From 07-JUL-08 16:50:00 to 07-JUL-08 16:50:00 (CST-6)
Location: CLARKSVILLE
Magnitude: 57.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Four large trees were downed.

Thunderstorm Wind in CASS, IOWA
From 07-JUL-08 20:30:00 to 07-JUL-08 20:30:00 (CST-6)
Location: ATLANTIC
Magnitude: 61.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Numerous large tree limbs and branches were downed.  One metal building was destroyed just north of Highway 6 and Ash.

Thunderstorm Wind in FRANKLIN, IOWA
From 07-JUL-08 16:33:00 to 07-JUL-08 16:33:00 (CST-6)
Location: BRADFORD
Magnitude: 56.00 MG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Storm Chaser

Thunderstorm Wind in GREENE, IOWA
From 07-JUL-08 15:43:00 to 07-JUL-08 15:43:00 (CST-6)
Location: CHURDAN
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

High winds downed trees.

Thunderstorm Wind in TAMA, IOWA
From 07-JUL-08 18:35:00 to 07-JUL-08 18:35:00 (CST-6)
Location: TOLEDO
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees were blown down in Toledo.

Thunderstorm Wind in WORTH, IOWA
From 07-JUL-08 13:33:00 to 07-JUL-08 13:33:00 (CST-6)
Location: GRAFTON
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Numerous large tree limbs down of greater than 6 inches in diameter.

Thunderstorm Wind in BLACK HAWK, IOWA
From 07-JUL-08 18:03:00 to 07-JUL-08 18:03:00 (CST-6)
Location: CEDAR FALLS
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Trees were downed at 9th and college.

Thunderstorm Wind in BLACK HAWK, IOWA
From 07-JUL-08 18:05:00 to 07-JUL-08 18:05:00 (CST-6)
Location: WATERLOO
Magnitude: 57.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Several large trees and numerous large branches were down along Highway 63 in the southern section of Waterloo.

Thunderstorm Wind in BLACK HAWK, IOWA
From 07-JUL-08 18:01:00 to 07-JUL-08 18:01:00 (CST-6)
Location: (ALO)WATERLOO MUNI A
Magnitude: 61.00 MG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: ASOS

Thunderstorm Wind in BOONE, IOWA
From 07-JUL-08 16:06:00 to 07-JUL-08 16:06:00 (CST-6)
Location: BOXHOLM
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Emergency Manager

A semi-tractor trailer was overturned with no injuries reported.

Thunderstorm Wind in BUTLER, IOWA
From 07-JUL-08 17:00:00 to 07-JUL-08 17:00:00 (CST-6)
Location: CLARKSVILLE
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Trees and power lines down in the city.

Thunderstorm Wind in FRANKLIN, IOWA
From 07-JUL-08 17:20:00 to 07-JUL-08 17:20:00 (CST-6)
Location: FAULKNER
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Several tree branches, some up to 12 inches in diameter, were downed.

Thunderstorm Wind in GRUNDY, IOWA
From 07-JUL-08 17:39:00 to 07-JUL-08 17:39:00 (CST-6)
Location: GRUNDY CENTER
Magnitude: 50.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Four to five inch diameter tree limbs down in Grundy Center.

Thunderstorm Wind in WEBSTER, IOWA
From 07-JUL-08 16:00:00 to 07-JUL-08 16:00:00 (CST-6)
Location: LANYON
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Two inch diameter tree limbs were broken. One and a half foot diameter tree snapped.

Flash Flood in MARION, IOWA
From 08-JUL-08 01:00:00 to 08-JUL-08 06:00:00 (CST-6)
Location: NEWBERN
Flood cause: Heavy Rain
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Many roads were covered by water in the area.  Rainfall was measured at 5.5 inches through 0600 CST.

Flash Flood in MARION, IOWA
From 08-JUL-08 04:30:00 to 08-JUL-08 06:00:00 (CST-6)
Location: MARYSVILLE
Flood cause: Heavy Rain
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Highway 5 was closed due to the North Cedar River flowing over the road.

Flash Flood in MONROE, IOWA
From 08-JUL-08 00:20:00 to 08-JUL-08 06:00:00 (CST-6)
Location: MELROSE
Flood cause: Heavy Rain
Property damage: 30.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Substantial street flooding was reported.

Flash Flood in MONROE, IOWA
From 08-JUL-08 00:00:00 to 08-JUL-08 06:00:00 (CST-6)
Location: ALBIA
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

A car stalled in the water at a low lying bridge underpass just north of town.

Flash Flood in MONROE, IOWA
From 08-JUL-08 02:00:00 to 08-JUL-08 06:00:00 (CST-6)
Location: SELECTION
Flood cause: Heavy Rain
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Public

Gravel road 637th trail was damaged, rutted, and partially washed out by heavy rain.  Overnight total was 4.25 inches.

Flash Flood in WARREN, IOWA
From 08-JUL-08 00:30:00 to 08-JUL-08 04:19:00 (CST-6)
Location: INDIANOLA
Flood cause: Heavy Rain
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Law Enforcement

High water from a rising creek was threatening numerous trailer homes at a trailer court in the south part of Indianola.

Thunderstorm Wind in BREMER, IOWA
From 07-JUL-08 17:10:00 to 07-JUL-08 17:10:00 (CST-6)
Location: WAVERLY
Magnitude: 52.00 EG
Property damage: 5.00K
Crop damage: 5.00K
Reported by: Trained Spotter

One quarter inch diameter hail occurred with the wind as well.