The Line Fire in Southern California has set over 20,500 acres ablaze and is 0% contained.

The wildfire was discovered Thursday, according to InciWeb's data. It's located in San Bernardino County, around 121 miles northeast of Los Angeles.

High temperatures have increased the fire's activity Sunday night and will continue through Monday, and then temperatures will be below normal by Wednesday.

The fire is spreading towards the northeast direction, according to Daily Press, a part of the USA TODAY Network. However, the cooler weather will help moderate the flames below the marine level.

Over 36,000 structures, including single and multi-family homes, commercial buildings, and others, are threatened by the fire, and thousands are forced to evacuate.

The fire also set areas of the San Bernadino National Forest ablaze.

A Damage Inspection Team was ordered, and there were 1,855 personnel assigned to fight the fire while more resources arrived from other parts of the California.

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What caused the fire?

The cause of the fire is under investigation.

However, as firefighting efforts continued on Sunday, rising temperatures allowed the fire to increase, according to InciWeb.

"Temperatures ranged from the upper 80s to the mid-100s over the fire area," stated its website.

Line fire map

State of emergency

California Gov. Gavin Newsom proclaimed a state of emergency and secured "a Fire Management Assistance Grant (FMAG) from the Federal Emergency Management Agency (FEMA) to help ensure the availability of vital resources to suppress the fire," stated a press release, as the fire grew over 17,400 acres on Saturday.

"It’s critical that residents in the impacted areas remain vigilant and prepare to evacuate immediately if called for by local authorities," said Newsom in a statement.

Evacuation orders

People in areas with evacuation orders are required to leave for their safety as "there is an immediate threat to life and property," according to InciWeb.

The following locations have been ordered to evacuate the area:

• The area from Calle Del Rio to Hwy 38, including Greenspot Road North
• Underdeveloped land from east of Highway 330 to Summertrail Place and north of Highland Avenue
• Areas of Running Spring east of Highway 330 and south of Highway 18
• Community of Running Springs
• Community of Arrow Bear Lake
• East of Orchard Road to Cloverhill from Highland Avenue north to the foothills
• North of Highland Avenue and East of Palm Avenue to Highway 330
• Garnett Street east to the 138 and Mill Creek north to the foothills
• Community of Forest Falls 
• Community of Mountain Home Village

The following areas have evacuation warnings:

Conditions may worsen in areas with an evacuation warnings. People in the following areas will need to evacuate should conditions change, according to InciWeb:

• Boulder Avenue east to Church Street
• Greenspot Road north to the foothills
• Church Street east to the city limit
• Area from the foothills south to Greenspot Road
• Green Valley Lake, north of Highway 18
• Community of Cedar Glen
• Community of Lake Arrowhead
• Community of Crestline
• Community of Valley of Enchantment
• Angelus Oaks
• Seven Oaks
• Garnet Street to Bryant Street and Carter Street North the Mill Creek 

Contributing: Rene Ray De La Cruz, Victorville Daily Press

Julia is a trending reporter for USA TODAY. She has covered various topics, from local businesses and government in her hometown, Miami, to tech and pop culture. You can connect with her on LinkedIn, follow her on X, formerly Twitter, Instagram and TikTok: @juliamariegz, or email her at [email protected].