A second, more powerful storm swept into Southern California Friday, bringing rockslides, downpours and flooding.
Heavy showers and thunderstorms are forecast through early evening, leading to the increased threat of flash flooding along the coast, valleys and mountains below the 5,500-foot elevation.
All canyon roads in Malibu were closed due to runoff, rockslides and debris from morning rainstorms. A flash flood warning was issued for parts of Los Angeles County, including burn areas in the Santa Clarita area.
A flash flood warning was issued until early Friday afternoon for parts of Ventura County, including the Solimar and Pines wildfire burn areas. The warning was issued due to rainfall rates of more than one inch per hour and the possibility of mud and debris flows.
One of the differences with this second storm is the increased instability, which means widespread lightning strikes along with the rain and snow, said NBC4 Meteorologist Anthony Yanez.
Winter storm warnings were issued for parts of Los Angeles, Riverside, San Bernardino and Ventura counties. High wind warnings are in effect for Orange, San Bernardino and Orange counties.
More than an inch per hour of rain is expected as heavy showers and scattered thunderstorms are forecast for the mid-morning hours Friday through early Friday evening, forecasters said. A few showers moved into the region late Thursday night and will continue to keep the roads wet overnight and through Friday morning's commute.
Officials advise residents to prepare for possibly dangerous situations.
- Malibu Canyon Road, from Malibu Crest Road at the city boundary to Piuma Road, due to a rock slide.
- Mt. Wilson Road, from Angeles Forest Highway to Mt. Wilson Circle.
- Upper Big Tujunga Road from the Angeles Forest Highway to the Angeles Crest Highway.
- Big Pines Highway, from Largo Vista Road to Angeles Crest Highway, is open with limited access; chains are required above 5,000 feet.
- Burbank Boulevard from Balboa Boulevard to 405 Freeway due to flooding.
A 75-foot pine tree fell in the middle of the road and downed some power lines Thursday night at Canyon Way in Pomona. Crews from SoCal Edison were working to cut down the tree piece by piece before they tried to restore power to about 30 residents who were left in the dark. The downed tree's roots were exposed as it lay on the road, indicating that heavy saturation from the persistent rain was the cause of the topple. The road was blocked until noon on Friday.
High surf is also expected through Monday, posing dangers to beachgoers and operators of small vessels and bringing the potential of coastal erosion and flooding. The storms have a potential to bring the highest surf the Central Coast has seen in recent years.
The first of three winter storms rolled into Southern California overnight Wednesday, bringing heavy rain in a region that's seeing its wettest winter in years.
The series of storms has pulled most parts of the state out of the severe drought category. Only 2 percent of the state -- one small region northwest of Los Angeles -- is under "exceptional drought," according to the weekly Drought Monitor report released Thursday.
NBC4 Wire Services contributed to this report.