Gusty Santa Ana winds, very low humidity, rising temperatures and dry vegetation will combine to put the Southland under the threat of wildfires beginning Thursday night, with forecasters saying fire conditions will persist through the weekend.
Click here for a list of affected streets in Northridge, Chatsworth and the rest of LA Council District 12.
Both Los Angeles and Pasadena reacted to the weather forecast by imposing parking restrictions on certain streets so that fire trucks will not be impeded and evacuation efforts stymied in case of emergencies.
The National Weather Service issued a red flag warning that will be in effect for most of Los Angeles County, with the exception of the Antelope Valley, from 9 p.m. Thursday through 6 p.m. Sunday.
A red flag warning will also be in effect for most of Orange County and all of western Riverside County from 2 a.m. Friday through 8 p.m. Sunday. In San Diego County, a red flag warning will take effect at 11 a.m. Friday and continue through 8 p.m. Sunday.
According to the NWS, a ridge of high pressure will build over the area tonight into Friday, continuing to move east over the weekend.
Along with the Santa Anas, "temperatures will range 5 to 10 degrees above normal with poor to moderate relative humidity recovery. Relative humidity is expected to fall sharply into the mid-teens to single digits Friday, and by Saturday, widespread single-digit humidity will extend from the higher elevations to the lower elevations."
Forecasters said northeast winds will average 30 to 40 mph, with gusts of up to 60 mph along ridges and canyons. Temperatures will be in the upper-70s to mid-80s in the mountains, in the upper-80s to low-90s in the valleys and in the mid-70s at the beaches.
According to the NWS, the conditions will be ripe for rapid fire growth, and if a blaze does ignite, "there could be rapid spread of wildfire that would lead to a threat to life and property."
In addition to the red flag warning, the NWS issued advisories pertaining just to the high winds. In the San Gabriel Mountains, a region that encompasses the Angeles National Forest in Los Angeles County and the Los Padres National Forest in Ventura County, a wind advisory was in effect this morning and scheduled to expire at 9 p.m. A more serious high wind watch will be in force in the same area from tonight through Saturday afternoon.
Northwest-to-north winds of between 20 and 35 miles per hour with 50-mph gusts will develop in the mountains today and persist through this evening, then will start blowing in a north-to-northeast direction at between 30 and 45 mph, with 70-mile-per-hour gusts possible, according to the NWS.
"Winds this strong will make for difficult driving of high-profile vehicles," said an NWS advisory, adding the strongest winds are expected late tonight through Saturday morning.
In the Santa Monica Mountains Recreational Area, a high wind watch will be in force from tonight through Saturday afternoon, with meteorologists forecasting winds of between 30 and 45 mph gusting to 70 mph. A high wind watch will be in effect during the same period in the San Fernando, Santa Clarita and San Gabriel valleys, the coast, downtown L.A. and other parts of metropolitan Los Angeles, the Hollywood Hills, and parts of Ventura County.
- City News Service contributed to this report.