(Reuters) -A fast-moving wildfire raged across thousands of acres of California prairie near the Nevada border on Friday, while Los Angeles was in the throes of back-to-back storms that could trigger flooding and mudslides in areas scarred by January's devastating wildfires.

Around 24 million people across California are under flood watches Friday morning as Los Angeles braces for what could be a month's worth of rain in a day.

The flood threat is increasing across Southern California this weekend, including Los Angeles and Santa Barbara. The heaviest rain will move in Friday night into Saturday and a few storms could bring gusty winds as well.

A flood advisory was issued by the NWS Sacramento CA on Thursday at 10:38 a.m. in effect until 7 p.m. The advisory is for Amador, Butte, Calaveras, Colusa, El Dorado, Glenn, Nevada, Placer, Sacramento,