As the relentless Santa Ana winds sweep through, a new fire threat emerged in Jurupa Valley, leaving residents on edge and firefighters racing against time.

A brush fire broke out in the Santa Ana River’s bottom in the Jurupa Valley area just before 5 p.m. Tuesday, Jan. 21, burning 39 acres before firefighters late that night stopped the blaze from spreading. As of Wednesday morning, Jan. 22, containment was at 45%.

Several counties in Southern California faced "critical" fire risks this week, according to an AccuWeather forecast.

The Santa Anas are expected to be most powerful Monday night into Tuesday. Fire services across the region say they are ready.

A rare Particularly Dangerous Situation warning has been issued for Southern California as a powerful and potentially damaging Santa Ana wind event​ is expected.

Santa Ana winds return to Southern California from Monday to Tuesday, once again raising fire danger concerns.

The Santa Ana winds are dry, powerful winds that blow down the mountains toward the Southern California coast. The region sees about 10 Santa Ana wind events a year on average, typically occurring from fall into January. When conditions are dry, as they are right now, these winds can become a severe fire hazard.

Critical fire conditions are expected to continue through Friday. But rain could be on the way this weekend. Here's what to know.

California Governor Gavin Newsom has deployed fire engines, water-dropping aircraft and hand crews across the region—to enable a rapid response if a new fire does break out, according to The Associated Press.

As wildfires continued to burn in Los Angeles, three fires broke out in San Diego County, prompting evacuation orders and warnings.

Jurupa Valley fire crews battled a brush fire in the Santa Ana River ... by 7 p.m., according to the California Department of Forestry and Fire Protection and the Riverside County Fire Department.

There are no evacuation orders in place now for the Eaton and Sepulveda Fires in LA County, the Clay Fire in Riverside County or the Laguna Fire in Ventura County. Evacuation orders were in place for areas near the Laguna Fire but have since been changed to evacuation warnings, according to Cal Fire.