The National Weather Service has issued an excessive warning for the Kern County desert areas, including Ridgecrest, Rosamond, California City, Mojave and Edwards Air Force Base. There is also a red flag warning in effect for critical fire weather conditions in the Los Angeles County mountains and Angeles National Forest. 

Today's peak high temperatures in the LA area likely pose the greatest fire risk, while gusty winds and low humidity create the potential for the fire to spread, the NWS said. 

In the Kern County desert areas, highs are expected to be between 105 and 112 degrees. The alert will be in effect from 10 a.m. Wednesday to 9 p.m. Thursday, and could be extended into Friday. 

The red flag fire warning is in effect until Wednesday evening. The Santa Clarita Valley and Santa Barbara and Ventura County mountains are also included in the alert.