A wild weather system lashed Southern California on Thursday with fierce thunderstorms that unleashed mudslides in wildfire-scarred canyons, spawned a tornado and dusted mountains and even low-lying communities with snow and hail.
The National Weather Service issued tornado warnings for parts of Riverside County about 55 miles east of Los Angeles and area residents flooded TV stations with pictures and video of funnel clouds and at least one tornado on the ground.
Powerful wind or a funnel cloud toppled a tractor-trailer on a highway and freight cars on nearby railroad tracks, said Riverside County fire spokeswoman Jody Hageman. One person was rescued from the wrecked truck.
"It got real windy, the sky got real dark," said James Smith, a manager at a fitness center at nearby March Air Reserve Base. He was not aware of any damage to the base.
Michael Ritter was scrambling to put away lawn furniture in his backyard in Riverside when he spotted a tornado and grabbed his camera.
"It looked like one of those dirt devils and then it got bigger. I've never seen anything remotely as big," Ritter said. "We could hear the wind from a mile away and see the debris flying up. I thought, that's the real thing."
Earlier in the day mud flows swept down canyons in neighboring Orange County.
Evacuation orders were issued to about 1,500 people in Williams, Modjeska and Trabuco canyons, areas devastated by a 28,000-acre wildfire last fall, said Orange County Fire Authority Capt. Mike Blawn.
A handful of residents at the top of Williams Canyon were temporarily stranded, fire officials said.
Aerial TV footage showed thick layers of mud surrounding homes as residents picked their way outside and began to clear properties with shovels. A road in Trabuco Canyon was impassable.
It was not known how many complied with the evacuation orders, which were lifted after a few hours.
April Brown, who runs a propane store in Modjeska Canyon with her husband, said she watched a creek swell during a half-hour downpour.
"You could just hear the boulders in the creek moving and popping and crashing into each other," Brown said. "I saw trees going down the creek."
The National Weather Service issued numerous flash-flood warnings through the day as thunderstorms pushed across the state's southern counties from metropolitan Los Angeles south to central San Diego County and eastward through Riverside and San Bernardino counties.
Localized street and freeway flooding swamped cars and jammed traffic around the region.
A layer of hail coated parts of Baldwin Park, a San Gabriel Valley suburb east of Los Angeles.
"It's amazing," said Kela Carbajal, a hair dresser at the Olive Square Barber Shop. "The kids go around grabbing at the snow and throwing it at cars."
Lightning sparked many brush fires in northern and eastern San Diego County but they were quickly doused, said Nick Schuler, a spokesman for the California Department of Forestry and Fire Protection.
In Santa Barbara County, firefighters kept watch on the weather and the potential for lightning, county fire Capt. Eli Iskow said.
"Our fuels are already dried out, primed and ready to burn so even with a little moisture in the air they're still going to burn," he said.
Residents of the San Bernardino Mountains communities northeast of Los Angeles awakened to snow-dusted peaks, and hailstorms peppered parts of the region. Quarter-inch hail fell as a huge thunderstorm blew through Ramona in San Diego County, said local airport employee David Boone.
Unusually cold late-season weather wasn't limited to Southern California, which just last weekend baked in 100-degree highs.
In the Sierra, about 2.5 inches of snow fell overnight in the Mammoth Lakes area and as much as six inches of snow in upper elevations there, said Scott McGuire, a meteorologist with the National Weather Service in Reno.
Lake Tahoe had as much as an inch of snow overnight above 7,000 feet. Squaw Valley reported an overnight temperature of 19 degrees, and the temperature remained at 25 degrees at 8,500 feet in the Lake Tahoe area at midday Thursday. Temperatures were in the upper 40s to low 50s at lake level, McGuire said.
"We really won't see a change in the pattern until next Tuesday or Wednesday," McGuire said. "We'll continue to have isolated showers through the entire holiday weekend. So kind of unsettled weather."
Southern California forecasts indicated rain and thunderstorms, and cooler-than-normal temperatures would continue into Memorial Day weekend.
In Central California, a National Weather Service surf advisory was in effect for wind-driven 10- to 14-foot waves, with some local sets to 18 feet along the coast of San Luis Obispo and Santa Barbara counties.
Overnight winds that gusted to 70 mph in some areas diminished Thursday but canyons and valleys still experienced winds. The NWS reported a morning gust of 53 mph at Saugus in northern Los Angeles County.
Tornadoes Rake Colorado, Wyoming
A large tornado skipped through several northern Colorado towns on Thursday, destroying dozens of homes, flipping tractor-trailers and freight rail cars, and killing at least one person.
The National Weather Service said the tornado touched down just before noon near Platteville, about 50 miles north of Denver. Over the next hour, it moved northward past several towns along 35-mile-long track toward Wyoming.
In Windsor, Colo., a farming town of 16,000 that was hardest hit, dazed residents retrieved what they could from their homes.
"I didn't want to see this. That's for sure," 41-year-old Windsor resident Alexander Martinez said while staring at a staircase, balcony, and personal belongings from his apartment that ended up in his front yard. The apartment's roof and a front wall had been torn away.
Nine people were hospitalized with various injuries at the Medical Center of the Rockies in Loveland, said spokesman Alex Stuessie. In Greeley, four people were treated for minor injuries at North Colorado Medical Center, said administrative representative Laurie Hamit.
Pete Ambrose, a caretaker at the campground outside Greeley, said he hid in a cinderblock restroom when he saw the twister approaching. A frightened camper who tried to outrun the storm in an RV was killed.
"I yelled at him to come with me and he tried to drive off," a despondent Ambrose said after emerging from his shelter, a cinderblock restroom.
The camper lay dead in the front seat of his RV. The rear half of the vehicle rested about 100 feet away. Weld County officials confirmed the man was killed but did not release his name.
"My house is gone," said Ambrose. "I lost my dog. I lost my cats. I lost my camper. I lost everything."
Crews removed downed power lines and poles from Windsor's streets Thursday evening and bulldozers cleared debris.
Several minor tornadoes were reported in northern Colorado on Thursday, the National Weather Service said. Meteorologist Jim Kalina said two or three major storm cells affected the area and that the weather service was trying to confirm how many tornados touched down.
Video footage of the large tornado showed a dark gray funnel perhaps a quarter-mile wide accompanied by heavy hail and rain.
Richard Dykstra, 65, was in his Windsor pest-control office with six other people when it began to hail and the roof began to slide off the building. "We had about 90 seconds, but we managed to get into the basement," Dykstra said.
He said he then ran to a day care center where his grandson was. No children were hurt, and they were herded into a vault at a nearby bank until the storm system cleared.
"It passed right over us like a big, white monster," said Thomas Coupe, 87, of Windsor.
The tornado overturned 15 railroad cars and destroyed a lumber car on the Great Western Railway of Colorado, said Mike Ogburn, managing director of Denver-based Omnitrax Inc., which manages the railroad. Fourteen of the overturned cars were tankers but they were empty.
All of northeastern Colorado was under a tornado watch through Thursday night, the National Weather Service said.
About 130 people waited at a Red Cross shelter downtown for friends to pick them up or evacuation orders to expire, but the shelter was moving to a nearby fairgrounds because of a lack of power. A second shelter opened at an events center in Loveland.
Gov. Bill Ritter declared a state of emergency for Weld County and toured the area. He said he talked to the Federal Emergency Management Agency about possible assistance.
Area police departments sent officers to patrol affected neighborhoods and deter looters, said Windsor Police Chief John Michaels.
Some 60,000 customers lost power in the area, but power was later restored to all but 15,000 of them, according to XCel energy. The company said it lost two large transmission lines and about 200 utility poles, and that it responding to several gas leaks at homes near Windsor.
The National Weather Service in Cheyenne, Wyo., was trying to verify whether a tornado touched down in Laramie, where a storm packing strong winds damaged several buildings and overturned vehicles Thursday afternoon. There were no reported injuries from the storm.
Meteorologist John Griffith said the agency would inspect the damage Friday before determining whether a tornado touched down.
"Indicators are very strongly in favor of it being a tornado, but normally we don't confirm yes or no until we send an inspection team to survey the damage," he said.
The storm damaged an apartment building and at least one house on the eastern edge of town, said Commander Dale Stalder of the Laramie Police Department.
On its Web site, the Wyoming Department of Transportation Web posted video showing a tractor trailer on its side and a boat that apparently had been blown off of a flatbed trailer on the Interstate 80.
Rocky Mountain Power said 7,300 customers in the Laramie area were without power Thursday evening.
Several tornadoes also touched down in western Kansas on Thursday, said Scott Mentzer, a National Weather Service meterologist in Goodland, Kan.
He said a few barely touched down, but that a couple moved along 30 to 50 miles on the ground in Sheridan and Decatur counties.
The tornadoes damaged several buildings, but there were no reported injuries.
About 100 people have died in U.S. twisters so far this year, the worst toll in a decade, according to the National Weather Service, and the danger has not passed yet. Tornado season typically peaks in the spring and early summer, then again in the late fall.
This could also prove to be the busiest tornado season on record in the United States, though the final figure on the number of twisters is not yet in.