California's worsening wildfires spark fresh evacuation orders

Red flag warnings are in effect over a vast stretch of the West — including California, Nevada and Montana, prompted by strong winds, high temperatures and drought conditions.

The latest: In Northern California, where fuel moisture and flammability are especially conducive to extreme wildfire behavior, the rapidly growing Caldor Fire prompted mandatory evacuation orders to be issued late Tuesday, as it tore through homes in and around the El Dorado County town of Grizzly Flats.

• County fire officials said at an evening community meeting that the wildfire had razed some 50 homes in the area. It has also left two people with serious injuries.

Zoom in: California Gov. Gavin Newsom proclaimed a state of emergency for the county earlier Tuesday due to the Caldor blaze — which ignited Sunday about 60 miles east of Sacramento and soon exploded in size. It was 0% contained and threatening at least 2,100 structures Tuesday, per the U.S. Forest Service's El Dorado division.

• Mandatory evacuation orders were issued for dozens of El Dorado County communities, including El Dorado County and places just south of Highway 50, according to the Forest Service.
• "In less than three days, the Caldor Fire has grown to over 30,000 acres," El Dorado National Forest officials said in an emailed statement announcing the forest's immediate closure early Wednesday.

Threat level: The fire could grow quickly throughout the day and into Wednesday as strong, shifting winds affect the region, leading to what the National Weather Service is calling "critical" fire danger.

• Per El Dorado National Forest officials: "Because the fire is not controlled and is actively burning, there is a high risk of flare-ups or uncontrolled runs within the forest."

Of note: Pacific Gas & Electric (PG&E), California's largest power company, announced plans to cut power to around 48,000 customers in parts of 18 counties in Northern California to reduce the risk of ignition from its equipment.

• The shutoff primarily affects Butte, Shasta Tehama counties, in which the Dixie Fire — the second-largest wildfire in California's recorded history — is burning.

• The Dixie Fire, which has torched at least 604,511 acres and was 31% contained, spread northeast Tuesday, triggering evacuation orders outside the town of Susanville, which has a population of around 18,000.

The big picture: Western states are in the grip of a prolonged, severe drought exacerbated by human-caused climate change that has exacerbated wildfire activity in recent years.

• Eight of the 10 largest fires in California's history have occurred in the past five years, according to CalFire.
• Studies show human-caused climate change is driving an increase in the likelihood and severity of heat waves and droughts, while also leading to bigger, more intense wildfires.

Go deeper: Excess COVID cases, deaths linked to wildfire smoke in new study

Editor's note: This article has been updated with new details throughout.