Hot and humid conditions prevailed across the region July 27, as a warm front lifted northward into northeast Iowa.  Showers and thunderstorms developed along the Highway 20 corridor in Dubuque, Jo Daviess and Stephenson Counties during the early evening hours of July 27.  They continued to redevelop and move over the same areas for about 18 hours.  Record-setting rainfall totals of 7 to 15 inches resulted in flash flooding of much of the area.  The Mississippi River at Dubuque, IA even rose about 4 feet in 12 hours due to the excessive rainfall.  In addition to the heavy rains and flooding, some of the stronger storms produced large hail and 2 brief tornadoes.  High temperatures on July 27 topped out in the lower and middle 90s.  Due to the high humidity levels, low temperatures the morning of July 28 only managed to slip into the 70s and lower 80s.

Flash Flood in DUBUQUE, IOWA
From 27-JUL-11 20:00:00 to 28-JUL-11 03:00:00 (CST-6)
Location: WHITE PINE HOLLOW SP
Flood cause: Heavy Rain
Property damage: 7.00M
Crop damage: 0.00K
Reported by: Law Enforcement

Torrential downpours of rain fell across much of Dubuque County during the evening of July 27 and early morning hours of July 28 resulting in flash flooding of much of the county, especially in Dubuque, IA.  Rainfall totals of 7 to 15 inches were common across the area, with most of the rain falling in under 12 hours.
Numerous roads and bridges were washed out and many others closed, causing Dubuque County to run out of barricades.  Several neighborhoods were evacuated, including the Valley Hill trailer park where the water was 6 feet deep.  Many creeks in the area raged out of their banks, including Catfish Creek. Very early estimates of damage to infrastructure alone exceeded $3 Million.  Numerous roads and streets were flooded, with some eroded or washed away completely.  Among the hardest hit areas was the vicinities of St. Mary's Catholic Church, Elm Street and the Millwork District.  The Dubuque water treatment plant was heavily damaged, with estimates between $1.5 Million and $2 Million.  A basement wall caved in at 1790 Chaney Road on Dubuque's West End.

Flash Flood in DUBUQUE, IOWA
From 27-JUL-11 18:24:00 to 27-JUL-11 21:00:00 (CST-6)
Location: ZWINGLE
Flood cause: Heavy Rain
Property damage: 1.00M
Crop damage: 0.00K
Reported by: Law Enforcement

Torrential downpours of rain fell across much of Dubuque County during the evening of July 27 and early morning hours of July 28 resulting in flash flooding of much of the county, especially in Dubuque, IA.  Rainfall totals of 7 to 15 inches were common across the area, with most of the rain falling in under 12 hours.  Significant street flooding began between 7 and 8 pm and escalated as the night continued.

Heavy Rain in DUBUQUE, IOWA
From 27-JUL-11 18:29:00 to 27-JUL-11 18:29:00 (CST-6)
Location: DUBUQUE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

As of 729 pm CDT July 27, the rainfall total 2 miles northeast of Dubuque, IA was 3.50 inches.

Hail in DUBUQUE, IOWA
From 27-JUL-11 18:29:00 to 27-JUL-11 18:29:00 (CST-6)
Location: DUBUQUE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Quarter sized hail fell 2 miles northeast of Dubuque, IA at 729 pm CDT July 27.

Heavy Rain in DUBUQUE, IOWA
From 27-JUL-11 20:30:00 to 27-JUL-11 20:30:00 (CST-6)
Location: ASBURY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

As of 930 pm CDT July 27, the rainfall total 4 miles west northwest of Dubuque, IA was 2.50 inches.

Heavy Rain in DUBUQUE, IOWA
From 28-JUL-11 05:00:00 to 28-JUL-11 05:00:00 (CST-6)
Location: ASBURY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

At 600 am CDT July 28, the rainfall total 2 miles west of Dubuque, IA was 7.06 inches and it was still raining.

Heavy Rain in DUBUQUE, IOWA
From 28-JUL-11 05:43:00 to 28-JUL-11 05:43:00 (CST-6)
Location: (DBQ)DUBUQUE MUNI AR
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

At 643 am CDT July 28, the 24 hour rainfall total 1 mile northwest of the Dubuque Regional Airport was 10.92 inches.

Heavy Rain in DUBUQUE, IOWA
From 28-JUL-11 06:40:00 to 28-JUL-11 06:40:00 (CST-6)
Location: PEOSTA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

At 740 am CDT July 28, the rainfall total in Peosta, IA was 13.10 inches and it was still raining.

Heavy Rain in DUBUQUE, IOWA
From 27-JUL-11 18:15:00 to 27-JUL-11 18:15:00 (CST-6)
Location: ASBURY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

At 715 pm CDT July 27, the 70 minute rainfall total 4 miles west northwest of Dubuque, IA was 1.60 inches.

Heavy Rain in DUBUQUE, IOWA
From 27-JUL-11 20:53:00 to 27-JUL-11 20:53:00 (CST-6)
Location: (DBQ)DUBUQUE MUNI AR
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

As of 10 pm CDT July 27, the 4 hour rainfall total at the Dubuque Regional Airport was 4.39 inches.  The hourly amounts were 0.17 inches from 6 to 7 pm, 0.40 inches from 7 to 8 pm, 1.54 inches from 8 to 9 pm, and 2.28 inches from 9 to 10 pm.

Heavy Rain in DUBUQUE, IOWA
From 27-JUL-11 23:29:00 to 27-JUL-11 23:29:00 (CST-6)
Location: ASBURY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

As of 1229 am CDT July 28, the rainfall total 4 miles west northwest of Dubuque, IA was 4.00 inches.

Heavy Rain in DUBUQUE, IOWA
From 27-JUL-11 17:39:00 to 27-JUL-11 17:39:00 (CST-6)
Location: ASBURY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

At 639 pm CDT July 27, the 20 minute rainfall total 4 miles west northwest of Dubuque, IA was 0.60 inches.

Thunderstorm Wind in DUBUQUE, IOWA
From 27-JUL-11 23:19:00 to 27-JUL-11 23:19:00 (CST-6)
Location: (DBQ)DUBUQUE MUNI AR
Magnitude: 51.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

A 59 mph wind gust was recorded by the ASOS at the Dubuque Regional Airport at 1219 am CDT July 28.

Heavy Rain in DUBUQUE, IOWA
From 28-JUL-11 06:59:00 to 28-JUL-11 06:59:00 (CST-6)
Location: KEY WEST
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

At 759 am CDT July 28, the rainfall total 4 miles south southeast of Dubuque, IA was 14.50 inches.

Heavy Rain in BUCHANAN, IOWA
From 28-JUL-11 08:30:00 to 28-JUL-11 08:30:00 (CST-6)
Location: INDEPENDENCE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

At 930 am CDT July 28, the rainfall total in Independence, IA was 3.00 inches.

Heavy Rain in DUBUQUE, IOWA
From 28-JUL-11 10:55:00 to 28-JUL-11 10:55:00 (CST-6)
Location: JULIEN
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

At 1155 am CDT July 28, the 24 hour rainfall total 4 miles southwest of Dubuque, IA was 15.10 inches.  This report was relayed by a media partner.

Hail in DUBUQUE, IOWA
From 27-JUL-11 18:17:00 to 27-JUL-11 18:17:00 (CST-6)
Location: DUBUQUE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Quarter sized hail fell 1 mile northeast of Dubuque, IA at 717 pm CDT July 27.

Hail in DUBUQUE, IOWA
From 27-JUL-11 18:20:00 to 27-JUL-11 18:20:00 (CST-6)
Location: DUBUQUE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Quarter sized hail fell 1 mile south southeast of Dubuque, IA at 720 pm CDT July 27.

Heavy Rain in DUBUQUE, IOWA
From 28-JUL-11 04:23:00 to 28-JUL-11 04:23:00 (CST-6)
Location: DUBUQUE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

At 523 am CDT July 28, the rainfall total 1 mile northeast of Dubuque, IA was 7.50 inches.

Hail in DUBUQUE, IOWA
From 27-JUL-11 18:20:00 to 27-JUL-11 18:20:00 (CST-6)
Location: CENTER GROVE
Magnitude: 1.25 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Half dollar sized hail fell in Dubuque, IA at 720 pm CDT July 27.

Heavy Rain in DUBUQUE, IOWA
From 27-JUL-11 18:18:00 to 27-JUL-11 18:18:00 (CST-6)
Location: DUBUQUE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

At 718 pm CDT July 27, the 1 hour rainfall total 1 mile northeast of Dubuque, IA was estimated to be 3.00 inches.

Heavy Rain in DUBUQUE, IOWA
From 28-JUL-11 06:00:00 to 28-JUL-11 06:00:00 (CST-6)
Location: (DBQ)DUBUQUE MUNI AR
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

At 700 am CDT July 28, the 13 hour rainfall total recorded by the ASOS at the Dubuque Regional Airport was 10.31 inches.

Heavy Rain in DUBUQUE, IOWA
From 28-JUL-11 05:00:00 to 28-JUL-11 05:00:00 (CST-6)
Location: DUBUQUE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

At 6 am CDT July 28, the 24 hour rainfall total at the COOP site at Lock and Dam 11 in Dubuque, IA was 8.80 inches.

Heavy Rain in DUBUQUE, IOWA
From 28-JUL-11 07:18:00 to 28-JUL-11 07:18:00 (CST-6)
Location: HOLY CROSS
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

At 817 am CDT July 28, the rainfall total in Holy Cross, IA was 7.50 inches.  This report was relayed by a media partner.

Heavy Rain in DUBUQUE, IOWA
From 28-JUL-11 10:37:00 to 28-JUL-11 10:37:00 (CST-6)
Location: (DBQ)DUBUQUE MUNI AR
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

At 1137 am CDT July 28, it stopped raining at the Dubuque Regional Airport.  The 24 hour total at this time was 10.62 inches, which actually fell within 18 hours!  This is a new 24 hour rainfall record for Dubuque, IA.  The previous record was 8.96 inches set on August 21 and 22, 2002.
In addition, a new daily rainfall record of 3.27 inches was established for July 28.  The previous record was 2.30 inches set in 1990.
This 24 hour total of 10.62 inches pushed the July total to a record 16.01 inches!  The previous July record was 12.68 inches set just last year in 2010.
In addition, the 16.01 inches July 2011 rainfall total also broke the all time monthly rainfall record!  The previous record was 15.46 inches set in September 1965.

Lightning in DUBUQUE, IOWA
From 27-JUL-11 18:30:00 to 27-JUL-11 18:30:00 (CST-6)
Location: DUBUQUE
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Newspaper

Lightning struck a spire on Bishop's Block Building at the intersection of 1st and Main Streets in Dubuque, IA during the evening of July 27 causing bricks to shoot out over the street below.  Some cars were damaged and a portion of the street was blocked.

Heavy Rain in DUBUQUE, IOWA
From 28-JUL-11 00:00:00 to 28-JUL-11 00:00:00 (CST-6)
Location: (DBQ)DUBUQUE MUNI AR
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

As of 100 am CDT July 28, the 7 hour rainfall total recorded by the ASOS at the Dubuque Regional Airport was 7.35 inches.  This made the daily rainfall total a record 7.47 inches. The previous record for July 27 was 3.10 inches set in 1896.  In addition, this total was also a July Daily Rainfall Record, surpassing the previous record of 6.28 inches established on July 1, 1961.

Heavy Rain in DUBUQUE, IOWA
From 28-JUL-11 03:49:00 to 28-JUL-11 03:49:00 (CST-6)
Location: ASBURY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

At 449 am CDT July 28, the 11 hour rainfall total 4 miles west northwest of Dubuque, IA was 8.50 inches.

Heavy Rain in DELAWARE, IOWA
From 28-JUL-11 04:50:00 to 28-JUL-11 04:50:00 (CST-6)
Location: EDGEWOOD
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

At 550 am CDT July 28, the rainfall total in Edgewood, IA was 3.07 inches.

Heavy Rain in DUBUQUE, IOWA
From 27-JUL-11 17:50:00 to 27-JUL-11 18:24:00 (CST-6)
Location: DUBUQUE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Just before 7 pm CDT, typical street flooding began in Dubuque with some sewer covers being blown off.

Flash Flood in JACKSON, IOWA
From 27-JUL-11 20:00:00 to 28-JUL-11 03:00:00 (CST-6)
Location: GARRY OWEN
Flood cause: Heavy Rain
Property damage: 1.50M
Crop damage: 0.00K
Reported by: Law Enforcement

Torrential downpours of rain fell across much of northeastern Jackson County during the evening of July 27 and early morning hours of July 28 resulting in flash flooding of much of the area. Rainfall totals of 7 to 15 inches were common across the area, with most of the rain falling in under 12 hours.
Several bridges were closed and roads washed out in northern Jackson County, including the bridge on 308th Street between Sieverding Ridge Road and U.S. 52, a wooden bridge in Tete De Morts Township on High Bridge Road, and a bridge on 248th Avenue.  Some culverts on 370th Street were destroyed.  Spruce Creek Park was evacuated.  Some basements in Bellevue were also flooded.  Annie's Acres along Mill Creek Road was also flooded.