Many valleys and inland communities can expect triple-digit temperatures through much of the week.
Pair that with sparse rainfall leading to bone-dry conditions, and firefighters are bracing themselves.
"We have not had any rain," said Michael Brown, a Los Angeles County fire battalion chief. "So all the vegetation, no matter where you are throughout Southern California, is extremely dry. That poses an extremely high fire danger and high risk for the firefighters on the ground."
On Sunday, a fire broke out in Irwindale near the Miller Coors brewery, south of the 210 Freeway. The flames scorched about 27 acres before firefighters were able to stop the forward progress. They remained on scene late Sunday on guard against flareups.
Irwindale brush fire burns 27 acres
Fire agencies plan to have extra crews and equipment on duty this week. Some wind gusts are expected to reach 40 mph in foothill communities.
Brown said the Santa Fe Dam Recreation Area has already seen a few fires in recent days.
"There's numerous homeless encampments throughout the whole park," he said. "Unfortunately in the last few days we've had numerous amount of fires in this area. With the weather conditions we've had the last few days, and the forecasted weather, it's still a great concern for firefighters."