Authorities said that a reversal in wind direction would test fire containment lines previously placed under quiet conditions, and push flames back into other areas.
Caldor Fire, the newest inferno, continues to grow rapidly in the Sierra Nevada southwest, Lake Tahoe. It covers 84 miles (2217.5 km) and has ravaged Grizzly Flats (a community of approximately 1,200).
There were at least 50 homes that were destroyed, but the totals are incomplete as officials weren't able to do thorough assessments of damage in Grizzly Flats. On Tuesday, two people were taken to hospital with serious injuries. The fire also threatened approximately 5,900 homes and other structures.
The Dixie Fire, which had been burning for a month in the Sierra-Cascades region, spread to 993 sq miles (2,572 km) two weeks after it destroyed Greenville, a Gold Rush-era community. The Dixie Fire threatened approximately 16,000 homes and other buildings. It was named after the road it originated.
Mark Brunton, chief of the firefighting operations section, stated in a briefing that "it's a pretty big monster."
He said, "We are not going to get it all overnight." It's going be a work-in-progress -- taking the elephant bite by bite -- and it will be a long-term mindset. It's a marathon, not a sprint.
Caldor and Dixie fires were among the dozen large wildfires that erupted in California's northern half. Southern California, however, has seen a few wildfires in recent years. Even Wednesday saw light drizzle and occasional rain, thanks to the ocean's humid air.
However, scenes of complete devastation have been left by the wildfires in Northern California.
In Grizzly Flats there were few homes left. Streets were littered by downed power lines, poles and other debris. The houses were reduced to smoldering metal and twisted steel with only chimneys rising from the ruins. The destruction of a post office and an elementary school led to the closure of both.
The ruins were littered with wrecked vehicles, and chairs skeletons sat in rows amid the ashes of a Church.
Derek Shaves fled Grizzly Flats on Monday night. He said he returned the following day to find that his house and many of his neighbors were gone.
He said, "It's just a heap of ash." "Everybody on my block was a pile of Ash and every block I visited -- except for five separate safe homes -- was completely destroyed."
On Tuesday, all 7,000 Pollock Pines residents were told to evacuate due to the fire.
Near the Dixie Fire, many firefighting resources were deployed to the area of Susanville. This city, which is about 18,000 people, is just a few miles away from the northeastern edge. Residents have been advised to evacuate.
Early Wednesday, fire officials stated that the fire had not moved toward Susanville overnight. However, there was one spot where wind direction changes to the northeast could have pushed flames backwards.
Pacific Gas & Electric shut down power supply to up to 51,000 customers in 18 Northern California county counties late Tuesday to avoid wildfires. This is the first time this has happened since last year's disastrous fire season.
According to the utility, shutoffs could continue into Wednesday afternoon as they were centered in the Sierra Nevada foothills and the North Coast mountains.
The blackouts were announced by the nation's largest utility as a precaution against wind gusts damaging power lines and setting off blazes.
PG&E has notified utilities regulators that the Dixie Fire may have been caused due to trees falling into its powerlines. The Dixie Fire started near Paradise and was destroyed by a wildfire that was ignited by PG&E equipment in strong winds. Eighty-five people died.
The Dixie Fire, which is nearly 100 large wildfires that have erupted in a dozen Western States, includes Alaska, is the largest. High temperatures, strong winds, and dry weather are the main factors that have fueled these wildfires.
According to scientists, climate change has made the U.S. West more dry and warmer over the past 30 years. It will also continue to make the weather extremer and more destructive.