Updates on California wildfires.
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Updated: 6:42 a.m. Sep. 20
First discovered: 4 days ago, 10:01 a.m. Sep. 16
Initial location: I-80 and Floriston Way, 9 miles northeast of Truckee, Nevada County, Calif.
Fire unit: Cal Fire Nevada-Yuba-Placer Unit;Nevada County Sheriff’s Office;Unified Command: California Highway Patrol;USFS – Humboldt-Toiyabe National Forest;USFS – Tahoe National Forest
Fire type: Wildfire
Fire name: Floriston Fire
Floriston Fire initially started at 10:01 a.m. Sep. 16 about I-80 and Floriston Way, 9 miles northeast of Truckee in Nevada County, California.
As of Sunday morning, 622 acres of land had been consumed by it. By Sunday morning, 45% of this fire was brought under containment. At this time, there are no details on the cause of the fire.
Fire containment
What does it mean for a fire to be 45% contained?
The percentage indicates how much of the fire perimeter has been surrounded by a control line. In this case, it means that 45% of the wildfire is halted from spreading, while 55% is still uncontrolled.
Containment is part of a larger plan for managing a wildfire. It is normally expressed as a percentage and it refers to how much of the fire perimeter has been surrounded/enclosed by a control line that firefighters create. The containment percentage indicates a certain level of control, but it doesn’t always correlate to safety level. Also, it’s important to note that containment doesn’t mean a fire is out.
How is containment measured?
The incident’s central command constantly receives progress reports from firefighters on the ground. As the fireline is constructed, inspected or reinforced, mappers record those details to adjust the containment percentage. The percentage tells the public how much of the fire perimeter is believed to not go beyond the control lines.
Source: Cal Fire
United Robots Sacramento
This story was originally published September 20, 2026 at 7:13 AM.