LOS ANGELES (CBSLA.com) — A red flag warning has been issued for parts of the Southland Thursday due to high temperatures, low humidity and windy conditions.

The warning was in effect for the mountains and valleys of Los Angeles and Ventura counties, the National Weather Service said.

It is scheduled to expire late Thursday afternoon to only be replaced by a fire weather watch through Friday afternoon.

Afternoon temperatures will climb into the 80s and 90s across the coastal and valley areas Thursday and between 90 and the low 100s by Friday, said an NWS statement said, adding that a peak in the heat is expected on Saturday with highs of around 106 degrees.

Forecasters said the area could expect winds between 15 and 25 mph, with gusts of 40 mph or more.

“As a result, widespread critical conditions are likely over much of Los Angeles and Ventura counties, especially the valleys and mountains,” warned an NWS statement, adding that it will become even hotter and drier from Thursday night through Saturday, but the winds will weaken each day.

Extremely dry vegetation amid the drought is a major concern for the wildfire threat, forecasters said.

“If fire ignition occurs there could be rapid spread of wildfire that would lead to a threat to life and property,” the NWS statement said.

The Los Angeles City and County fire departments will deploy additional resources, including extra firefighters and engines, “around the clock” throughout the weather event.

These additional firefighters will be deployed at select neighborhood fire stations serving high-hazard brush areas for at least a 24-hour period, with focus placed on the Porter Ranch area, Bel Air, Beverly Glen, Sun Valley and the Shadow Hills area, La Tuna Canyon, Encino, Sylmar, Laurel Canyon, Mulholland Drive and the West Hills/Canoga Park area.

(©2014 CBS Local Media, a division of CBS Radio Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. Wire services contributed to this report.)