A line of thunderstorms developed in extreme northeast Nebraska in response to an increasing low level jet feeding in very moist and unstable conditions into a weak nearly stationary front in the region.  The thunderstorms tracked repeatedly across the same region producing locally very heavy rain and some flash flooding.

Flood in KNOX, NEBRASKA
From 22-JUL-10 04:00:00 to 23-JUL-10 05:15:00 (CST-6)
Location: VERDEL
Flood cause: Heavy Rain
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Rainfall of at least 4 to 8 inches fell across the lower Niobrara River basin late in the evening of the 21st into the early morning hours of the 22nd.  This caused the Niobrara River to flood across the Jct of Highways 12 and 14 near Niobrara swamping at least one vehicle.  A few other roads in the area also flooded.  At its peak almost 20,000 cfs of water was flowing down the Niobrara, compared to normal flows of 1,000 cfs.  According to NPPD records, spillway gates from an upstream reservoir were opened for the first time since 1966 to relieve water pressure against the dam.  The high water also flooded a local golf course and surrounding agricultural land.

Flash Flood in KNOX, NEBRASKA
From 22-JUL-10 03:30:00 to 22-JUL-10 04:30:00 (CST-6)
Location: VERDEL
Flood cause: Heavy Rain
Property damage: 15.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Rainfall of 4 to 6 inches fell in about a 4 to 6 hour period along the Ponca Creek basin.  The heavy rain caused a rapid rise of Ponca Creek which flooded areas along the creek east and west of Verdel.  Some county roads and Highway 12 near the creek were flooded along with agricultural lowlands.  Several washouts of county roads occurred.

Flood in KNOX, NEBRASKA
From 22-JUL-10 04:30:00 to 22-JUL-10 22:00:00 (CST-6)
Location: NIOBRARA
Flood cause: Heavy Rain
Property damage: 35.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Rainfall of at least 4 to 8 inches fell across the Ponca Creek basin from late in the evening of the 21st into the early morning hours of the 22nd.  The heavy rain caused flooding along Ponca Creek for much of July 22nd.  The creek near Verdel crested a little over 14.5 feet during the early afternoon hours of the 22nd, flood stage is 12 feet.  The flooding caused numerous washouts of county roads and and also flooded Highway 12 along with agricultural lowlands.  Several culverts needed replacement after the flood.  There was also significant flooding of a resort near the Missouri River close to where Ponca Creek flows into it with over 2 feet of water reported in the campground.

Flood in KNOX, NEBRASKA
From 22-JUL-10 10:05:00 to 22-JUL-10 14:05:00 (CST-6)
Location: NIOBRARA
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Rainfall of 4 to 6 inches fell across much of this area during the night of July 21st and 22nd.  The heavy rain produced flooding along Bazile Creek which flooded across Highway 12 east of Niobrara depositing some debris and causing its temporary closure.  A Few county roads in the area were also flooded as were agricultural lowlands near the Creek.

Heavy Rain in KNOX, NEBRASKA
From 22-JUL-10 07:15:00 to 22-JUL-10 07:15:00 (CST-6)
Location: VERDEL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Twenty-four hour rainfall of a little over 6 inches was measured by the cooperative observer south of Verdel, although most fell in about a 4 to 6 hour period.

Flood in PIERCE, NEBRASKA
From 22-JUL-10 09:00:00 to 22-JUL-10 11:00:00 (CST-6)
Location: OSMOND
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Rainfall of 3 to 4 inches fell near and north of the Osmond area during the overnight hours of July 21 and 22nd.  This caused some minor flooding across Highway 20 a few miles east of Osmond with about 4 inches of water reported across the highway for a while during the morning of the 22nd.  Little or no damage was reported.

Flash Flood in KNOX, NEBRASKA
From 22-JUL-10 01:00:00 to 22-JUL-10 04:30:00 (CST-6)
Location: VERDEL
Flood cause: Heavy Rain
Property damage: 20.00K
Crop damage: 0.00K
Reported by: COOP Observer

Rainfall of 5 to 6 inches fell south of Verdel causing flash flooding along small creeks in the area.  According to the cooperative observer south of Verdel the flooding washed out 6 to 7 small earth dams as water around a quarter mile wide flooded out trees, fences and other objects in its path in the area.