Communities on Wednesday were cleaning up from a big December storm that brought rain, flooding, mudslides to Southern California.
A powerful storm system slammed the Southland Tuesday with heavy rain, high winds, and mountain snow, leading to flooded roadways, dangerous driving conditions, and mud and debris flows in recent burn areas.
By 8 a.m., some mountain and foothill areas had already received as much as 7 inches of rain, while coastal and valley areas had received between 1 and 3 inches, according to the National Weather Service.
"Rain, heavy at times, and high elevation snow will continue through the afternoon. Gusty and potentially damaging winds are expected over the area today as well," according to the NWS.
Forecasters noted there is still a threat of some thunderstorms developing, meaning the potential for even heavier downpours and continuing the risk of flooding.
A mandatory evacuation order has been given for the Silverado Canyon area in the area of the Bond Fire burn scar.
Caltrans Tuesday night advised against travel on Interstate 15 in Cajon Pass as they expect snow.
The National Weather Service issued a flash flood warning for Irving, Laguna Hills and Laguna Beach before expiring Tuesday afternoon before 2 p.m.
The San Bernardino County Sheriff’s Department issued an evacuation warning – not an order – for the following areas: Yucaipa’s North Bench, Mountain Home Village, Angelus Oaks, Forest Falls, and Lytle Creek.
An evacuation order for the community of Oak Glen was lifted by noon on Wednesday.
The National Weather Service said that residents in these additional burn fire areas should be prepared to evacuate: Alisal, Palisades, Bobcat, Ranch2, Dam, Lake.
Mandatory evacuations for Modjeska, Silverado and Williams canyons were lifted Tuesday night, hours after the orders were originally in effect.
Redlands East Valley High School – 31000 E. Colton Ave., Redlands, CA 92374
Animal evacuation center — San Bernardino County Animal Care & Control – 1-800-472-5609.
Lake Forest Sports Park — 28000 Rancho Parkway
Albert A. Chatigny Senior Community Center — 1310 Oak Valley Parkway, Beaumont, CA 
Multiple mudslides were reported Tuesday afternoon in the Silverado Canyon area of Orange County. Orange County Fire Authority firefighters reported rescuing trapped residents but said no injuries were reported.
Multiple mudslides were reported Tuesday afternoon in the Silverado Canyon area of Orange County. Orange County Fire Authority firefighters were working to rescue trapped residents but said no injuries were reported.
Mud and debris flow was also reported in the San Bernardino National Forest.
The westbound lane of Foothill Boulevard in Rialto has been closed between Cactus Avenue and Spruce Avenue due to flooding.
In Palmdale, Pine Canyon Road has been closed to westbound traffic, and Lake Hughes Road has been closed to southbound traffic. The LA County Sheriff's Department also advises drivers stay away from Elizabeth Lake Road because of debris and minor flooding.
In Castaic, Lake Hughes Road were closed between mile marker 5.99 and mile marker 9.02.
Glendora Ridge Road and Glendora Mountain Road were closed until further notice due to rock slides.
Knott's Berry Farm reported that it will be closed Tuesday because of the weather. The market however will remain open.
Six Flags Magic Mountain also announced it will be closed Tuesday. All tickets bought for today will be valid through the end of December.
About 2,400 Los Angeles Department of Water and Power customers were without power Tuesday morning. As of about 10 a.m. Tuesday, the following outages were reported:
And roughly two dozen outages affecting about 9,000 customers were reported in unincorporated areas in Los Angeles County, according to Southern California Edison.
By 2 p.m. Thursday, thousands of customers in Riverside County were also without power, Riverside Public Utilities said. 
The storm brought high winds, with gusts up to 73 mph recorded in some mountain areas and from 30 to 45 mph in coastal and valley areas.
Snow also fell in the mountains at elevations of 6,000 to 7,000 feet. Forecasters said earlier that as much as three feet of snow could accumulate in the mountains.
People are headed to Big Bear to enjoy the freshly-fallen snow that came down Tuesday, while crews are still working on cleaning roads and walkways.
The City of Malibu announced Tuesday morning that all traffic signals on the Pacific Coast Highway between Cross Creek Road and Coastline Drive. The traffic signals were working again by 1:30 p.m.
The storm will be accompanied by chilly temperatures, with daytime highs in the 50s Monday and Tuesday and lows dropping into the 30s Tuesday night in the mountains and parts of the San Fernando Valley, and into the 20s in the Antelope Valley.
Beach erosion is another potential problem caused by the storm expected to hit the LA area Monday. The LA County Department of Beaches and Harbors will not be offering sandbags this year.
Reports of flooding amassed throughout the morning rush hour. In northern Los Angeles County, a stretch of Lake Hughes Road had to be closed due to mud and debris that cascaded over the roadway in Castaic.
Near Los Angeles International Airport, stormwater flooded at least one southbound lane of the Sepulveda Boulevard tunnel, leading to traffic delays as crews worked to clear the water.
Fire crews were on high alert near the Los Angeles River, which was filled with a rushing torrent of water as the storm continued. Around 9 a.m., firefighters responded to the river near Washington Boulevard in the downtown area due to a car that was reported to have gone into the water. Another person was plucked from the river in the Sylmar area.
Health officials advise the public not to swim or surf in ocean waters at and around discharging storm drains, creeks and rivers after significant rainfall due to a possible increase in bacteria, chemicals, debris, trash and other public health hazards.
The rain is expected to keep falling through the afternoon, tapering off by late afternoon and leading to a dry Wednesday, before a much smaller, much weaker storm moves into the area Thursday.
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The Los Angeles Fire Department issued a series of reminders Sunday related to the potential for mud and debris flow. Among them were:
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