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.

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

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%.

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.

The backstory: Russian thistles, better known as tumbleweeds, arrived in South Dakota in the 1870s most likely via a shipment of flaxseeds from Russia that was contaminated with the invasive seeds. Read on... for more on what scientists are doing to combat the invasive species.

Weekend rains could bring some relief to Southern California. Here's the forecast and an assessment of how much it will help reduce fire risk.

Trump makes wild claims about California wildfires and snubs Newsom ahead of visit - The Border 2 fire has torn over 4,200 acres in San Diego County ahead of President Donald Trump’s visit to survey w