Live California fire updates: Crews make progress as victims demand return to decimated neighborhoods

A major factor explaining the rapid spread of wildfires this winter is how painfully dry the skies have been, which has plunged into the peak of the Santa Ana wind season.

“Santa Claus is very common in December, January, and that’s usually when we see our strongest and biggest and most damaging. But we’re not having as dry conditions as usual,” said Alex Tardy, a meteorologist at the National Weather Service office in San Diego.

January is the peak season for Santa Ana winds — strong winds that develop when high pressure over Nevada and Utah sends cold air screaming toward areas of lower pressure along the California coast. The air dries out and is compressed and heated as it flows downslope from the high deserts—from the northeast—over California’s mountains and through canyons, drying out vegetation as the wind blows through.

The Santa Ana season generally starts in October and lasts through March, but the magnitude of Santa Ana winds is typically strongest in January, Tardy said, citing research by the US Forest Service and the Scripps Institution of Oceanography. January is in the heart of a typical California rainy season.

For many areas in Southern California, “this is the driest start to any water year,” Tardy said, “and you can see extreme fire behavior with the ignitions.”

The only way Southern California will see lasting relief from this tough fire season is rain. And unfortunately, there is still no significant chance of rain until January 25, forecasters say.

Downtown Los Angeles has received just one drop of water in months — just 0.16 inches since Oct. 1, or just 3% of the seasonal average. Typically, by this time in the water year, downtown Los Angeles has received an average of 5.45 inches of rain. The annual average is 14.25 inches.

“As long as we go without seeing rain, it just doesn’t take much. The vegetation is just starving for moisture, and then when you get the wind on top of that, there’s definitely potential for fire behavior” after an ignition, Tardy said.

Fire weather is expected to improve from Wednesday evening to Saturday. But from around Monday there is a moderate risk of another round of red flag warnings.