Update: Wimer Fire in San Joaquin County remains fully contained by Monday evening

Published May 19, 2026 #Wimer fire

Updated: 10:07 p.m. May 18

First discovered: 9 hours ago, 1:07 p.m. May 18

Initial location: Hwy 26 and Shelly Road, Linden, San Joaquin County, Calif.

Fire unit: Cal Fire Tuolumne-Calaveras Unit

Fire type: Wildfire

Fire name: Wimer Fire

Wimer Fire initially started today at 1:07 p.m. at Hwy 26 and Shelly Road, Linden in San Joaquin County, California.

It has burned 46.3 acres after being active for nine hours. As of Monday evening, the blaze has been fully contained by a crew of six firefighters. The cause of it remains under investigation.

Among other resources, two engines have also been assigned to fight the wildfire. According to Cal Fire, “Numerous firefighting air tankers from throughout the State are flying fire suppression missions as conditions allow.”

Fire containment

What does 100% containment mean?

Note that full containment doesn’t mean the fire is completely out. In this case, it means that the wildfire has been fully enclosed by a control line and it is now stopped from spreading. A fully contained wildfire may continue to burn within the containment perimeter but is not likely to spread.

However, there’s a significant difference between containing and controlling a wildfire. After the fire is fully contained, the next step is to control it. Controlling a fire means ensuring that the fire can’t spread or cross the containment line.

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