Thunderstorms producing heavy rain led to several flash floods across southern Utah in the middle of September. A few of these floods were located in and around Zion National Park. One report of large hail was also received during this time period.

Flash Flood in KANE, UTAH
From 15-SEP-11 14:30:00 to 15-SEP-11 16:30:00 (MST-7)
Location: GLEN CANYON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Park/Forest Service

The Big Water Visitors Center reported a very large flash flood in the Wahweap drainage.

Hail in EMERY, UTAH
From 16-SEP-11 15:06:00 to 16-SEP-11 15:06:00 (MST-7)
Location: MOORE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hikers who were caught in Crack Canyon during a thunderstorm reported hail that was approximately 1 inch in diameter.

Flash Flood in WASHINGTON, UTAH
From 13-SEP-11 16:45:00 to 13-SEP-11 17:45:00 (MST-7)
Location: ZION LODGE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Park/Forest Service

Large flash floods were reported in Pine Creek and Clear Creek in Zion National Park, with flowing water as much as 7 to 8 feet deep.

Flash Flood in WASHINGTON, UTAH
From 14-SEP-11 13:40:00 to 14-SEP-11 15:40:00 (MST-7)
Location: SPRINGDALE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Flash flooding was reported in Zion National Park along the East Fork of the Virgin River, with the gauge along this river rising to 1665 cfs.

Flash Flood in WASHINGTON, UTAH
From 14-SEP-11 15:30:00 to 14-SEP-11 17:30:00 (MST-7)
Location: BLOOMINGTON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy rain over the Fort Pearce Wash caused flash flooding along that drainage, with the measured flow at the gauge going from 0 cfs to 763 cfs in a single hour.

Flash Flood in KANE, UTAH
From 15-SEP-11 16:10:00 to 15-SEP-11 18:10:00 (MST-7)
Location: (U17)BULLFROG (AMOS)
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Park/Forest Service

Flash flooding was reported along Fortymile Creek.

Flash Flood in KANE, UTAH
From 15-SEP-11 19:00:00 to 15-SEP-11 21:00:00 (MST-7)
Location: ADAIRVILLE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy rain caused flash flooding along the Paria River drainage. The gauge on the Paria near Kanab went from 185 cfs to 1212 cfs in one hour.

Flash Flood in WASHINGTON, UTAH
From 16-SEP-11 14:30:00 to 16-SEP-11 16:30:00 (MST-7)
Location: GRAFTON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Park/Forest Service

Flash flooding occurred in many locations of Zion National Park, with floods reported over a large portion of the southern half of the park. Pine Creek and Spry Canyon both experienced large floods, with water in Pine Creek reportedly 6 to 7 feet high. Large rocks and other debris impacted some of the roads around the park. In addition, many of the smaller drainages that flow south to Rockville experienced flooding.

Flash Flood in EMERY, UTAH
From 16-SEP-11 15:00:00 to 16-SEP-11 17:00:00 (MST-7)
Location: MOORE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Park/Forest Service

Flash flooding occurred in Crack Canyon, Little Wildhorse Canyon, and other washes near the Little Wildhorse Canyon trailhead. The floods were generally large and hikers caught in Crack Canyon had to run from the water, eventually making it back to the road before the water caught up with them.

Flash Flood in WAYNE, UTAH
From 17-SEP-11 06:00:00 to 17-SEP-11 21:00:00 (MST-7)
Location: GROVER
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Moderate to heavy rainfall fell over a broad area near Capitol Reef National Park. This initially caused flash flooding along Sulphur Creek and other parts of Capitol Reef. Eventually this water made its way downstream, causing flash flooding along the Dirty Devil River, which went from 538 to 1419 cfs in a few hours.