The fire burned 19,904 acres (8,055 hectares), destroyed and damaged hundreds of buildings, and caused multiple injuries.

The Mountain Fire began shortly before 9:00 a.m. PST on November 6 during an episode of strong Santa Ana winds in Southern California.

[2] The National Weather Service's Storm Prediction Center delineated an "extremely critical" risk area on their Day 1 fire weather outlook, warning of low relative humidity values combined with a strong wind event with gusts of over 65 miles per hour (105 km/h).

The Los Angeles Times called it "the most extreme Santa Ana wind event to hit Southern California in years".

Besides the homes, outbuildings, fences, irrigation lines, and other farming equipment, the fire damaged or destroyed avocado, citrus and berry crops.