What to Know
Snow and rain are expected into Tuesday with the first system
A second storm system is due to arrive Thursday after a break on Wednesday
Hazardous travel conditions are possible in mountain areas, including the 5 Freeway north of LA
A cold storm system that gained strength in the eastern Gulf of Alaska brought rain and snow to Southern California, marking the first of this week's two winter blasts.
The storm moved across Northern California early Monday, bringing rain to to the Bay Area and snow in the Sierra Nevada Mountains. The system arrived in Southern California by Monday evening.
"We're going to have to watch for possible downpours in those burn scar areas," said NBC4 forecaster Shanna Mendiola.
A second round of rain and snow is possible Thursday into Friday. The storm is likely to bring more widespread rain, increasing the flood threat in burn areas.
In Santa Barbara County, pre-evacuation notices were issued for areas below the Thomas fire burn area, including Montecito. Neighborhoods were overrun by an onslaught of mud and debris after a downpour early Jan. 9 touched off a mudflow in the coastal community northwest of Los Angeles.
Santa Barbara County's pre-evacuation advisory is the lowest level of a new three-tier warning system. The storm is expected to arrive in the area around Monday afternoon.
It appears that there's only a 10-20 percent chance of runoffs and debris flows in L.A. County down slopes previously denuded by wildfires, including at the site of last September's La Tuna Fire in the Verdugo Mountains.
Snow is expected at low elevations, including in the Antelope Valley and the 5 Freeway in northern Los Angeles County. The snow, which will also fall in Ventura and Santa Barbara County, will last from Monday evening to Tuesday evening.
A winter weather advisory will be in force in the San Gabriels until 10 p.m. Tuesday and in the Antelope Valley. The snow level could dip as low as 2,500 feet.