By GILLIAN FLACCUS and KEN RITTERAssociated Press
SANTA ANA, Calif. (AP) - Wild summer thunderstorms slammed parts of the Southwest, stranding residents in Navajo Nation in their homes in northern Arizona and leaving an already squalid mobile home community in Southern California deep in water and worry.
A thunderstorm dropped more than the average annual rainfall on parts of California's Coachella Valley in one night alone, settling for six to eight hours over Mecca and Thermal, two towns 150 miles southeast of Los Angeles near the location of the annual Coachella Music Festival.
In Thermal, the downpour flooded the dilapidated Desert Mobile Home Park better known as Duroville, a community of mostly migrant workers with about 1,500 people, including 900 children, that has long been the subject of legal fights as Riverside County officials attempt to relocate residents.
More than a foot of water stood in the southern end of the park, knocking out power to about 800 people for much of the day.
"None of us had ever been through anything like this," said Tom Flynn, the court-appointed receiver for Duroville. "That much water in a dilapidated mobile home park was something to see."
The lack of power knocked out electric motors on both of the park's wells, leaving no fresh water until one was revived and county workers brought several tons of bottled water.
The park has no paved streets or drainage, and health officials were concerned about overflow from two ponds that serve as the community's sewers.
Between 60 and 80 people had evacuated from the park and were spending the night at a high school. "The poorest of the poor were hit the hardest," Flynn said.
St. Anthony's Mobile Home Park in Mecca also was affected, but fared better than Duroville. Video clips showed residents wading through knee-high water and cars creeping through flooded residential streets.
The storm dropped 5.51 inches of rain near Mecca and 3.23 inches of rain near Thermal, meteorologist Mark Moede said. The average annual rainfall in arid Thermal is just shy of 3 inches, he said.
"That's an amazing amount of rain," Moede said. "It's unusual anywhere to get a storm that sits stationary for five to eight hours."
In the Las Vegas area, a separate system of intense thunderstorms flooded washes, delayed flights, snarled traffic and prompted helicopter rescues of stranded motorists, authorities said.
Television news video showed school buses inching along roads after school east of downtown Las Vegas, and muddy water up to the lower sills of windows of stucco homes in other neighborhoods.
In southeast Las Vegas, authorities recommended that the residents of about 45 homes damaged by flooding should leave in case electrical fires are sparked. The Clark County fire department went door-to-door late Tuesday suggesting that residents leave as a precaution, said county spokesman Dan Kulin.
A Twitter photo showed dozens of cars swamped by water up to their headlights in a parking lot outside the Thomas & Mack sports arena at the University of Nevada, Las Vegas.
Firefighters responded to more than 20 calls about people in stalled cars, Kulin said. Despite numerous 911 calls, officials in Clark County, North Las Vegas, Henderson and Las Vegas said no serious injuries were reported.
A Las Vegas police helicopter was dispatched during the height of the storm to pluck several people from swamped vehicles on roadways, Officer Bill Cassell said.
National Weather Service meteorologists said more than 1.75 inches of rain were reported in downtown Las Vegas. The rainfall amounts put the region on pace to exceed the 4.5 inches of rain it normally gets in a year.
On the Navajo Nation reservation in northeastern Arizona, many of Tuba City's roads were underwater and residents stuck in their homes. State Route 264, one of two main arteries in and out of town, was closed after a bridge washed out about a mile outside of the community, Tuba City Chapter Manager Benjamin Davis said.
Flooding was reported in some homes but no residents were displaced, Davis said.
Meanwhile, a dike that broke during heavy morning rain flooded nearly four square blocks in the southern Utah city of Santa Clara. More than 30 homes and business were evacuated after the break.
City Manager Edward Dickie said the dike along a retention pond sent a deluge of water into downtown.
"It didn't just breach. It broke. It's gone," he said, adding that the flooding quickly receded as water drained into rivers and creeks.
Ritter reported from Las Vegas. Associated Press writers Andrew Dalton and Shaya Mohajer in Los Angeles and Brian Skoloff in Salt Lake City contributed to this report.
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