Firefighters responded to more than 20 calls about people in stalled cars, said county spokesman Dan Kulin. A Las Vegas police helicopter was dispatched during the height of the storm to pluck several people from swamped vehicles on area roadways, said Officer Bill Cassell.
After responding to numerous 911 calls, officials in Clark County, North Las Vegas, Henderson and Las Vegas said Tuesday there were no confirmed reports of serious injuries.
National Weather Service meteorologist Michael Staudenmaier 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, he said.
However, National Weather Service meteorologist Scott Sukup said the Nevada showers weren't part of the same storm system that doused parts of Southern California.
There, a thunderstorm that dropped more than the average annual rainfall on parts of the Coachella Valley in one night alone caused flooding at two mobile home parks, forced road closures and dampened a school, officials said Tuesday.
The early morning thunderstorm stalled for six to eight hours over Mecca and Thermal, two towns at the southern tip of the Coachella Valley 150 miles southeast of Los Angeles. Thermal is about eight miles from Indio, California, where the annual Coachella Music Festival is held.
The storm dropped 5.51 inches of rain near Mecca and 3.23 inches of rain near Thermal, said meteorologist Mark Moede. The average annual rainfall in Thermal is just shy of 3 inches, he said.
"That's an amazing amount of rain," said Moede. "It's unusual anywhere to get a storm that sits stationary for five to eight hours. The fact that it occurred in the southern part of the Coachella Valley is even more unusual because it's typically a very arid part of the country."
In Thermal, the downpour flooded the dilapidated Desert Mobile Home Park better known as Duroville, a community that includes migrant workers, about 900 of whom are 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, leaving about 800 people without power for much of the day, but by nightfall only 11 mobile homes remained in the dark.
"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 meant electric motors on both of the park's wells were broken, 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 Mecca residents wading through streets with water reaching their knees and cars creeping through flooded residential streets.
Flooding also was reported at Mecca's Saul Martinez Elementary School, but students doubled up in some classes and the school remained open, The Desert Sun newspaper reported.
Meanwhile, some southern Utah residents also were dealing with flooding because of a broken dike.
Officials in Santa Clara were inspecting whether people could return to more than 30 homes and businesses that were evacuated after the Tuesday break flooded nearly four square blocks.
City Manager Edward Dickie said the dike along a retention pond broke open after heavy morning rains, sending 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.
Some streets through town remained closed late in the day as authorities assessed the damage and waited for flood waters to recede. No injuries were reported.
Crews used sandbags to shore up the broken dike and stave off the potential for additional flooding if the rain returns.
Associated Press writers Shaya Mohajer in Los Angeles and Brian Skoloff in Salt Lake City contributed to this report.
Intellpuke: You can read this article by Associated Press Writer Ken Ritter, reporting from Las Vegas, Nevada, in context here: www.guardian.co.uk/world/feedarticle/10434472