Rim Fire spokesman Brian Haines pinpointed the origin of the fire to one location: The Jawbone Ridge in Tuolumne County, which sits on Groveland Ranger District land, at the point where the Clavey River and the Tuolumne Wild and Scenic River meet up.
The numbers are moving in the right direction.
On Tuesday, Cal Fire reported the Rim Fire burning in the Yosemite region is now 75 percent contained, and the acreage burned held steady overnight at 235,841 acres, or 368 square miles – more than seven times the size of San Francisco. In addition, the number of firefighters battling the blaze in the steep, rugged terrain has dropped to 4,359 - down from the high of more than 5,000 firefighters called in over the last two weeks.
The containment should only grow, said Cal Fire spokesman Dave Berlant, as the weather forecast for Northern California should see cooler temperatures and even some possible rain. Still, the expected full containment date is Sept. 20.
The fire has been burning since Aug. 17 in the Stanislaus National Forest near Yosemite National Park.
The official cause is still unknown, although one fire chief in the nearby town of Twain Harte raised questions when he told a community group on Aug. 23 that it was possible a marijuana grow operation could be to blame. That chief, Todd McNeal, has not returned phone calls to NBC Bay Area on Monday or Tuesday to clarify his comments.
A Rim Fire spokesman on Monday told NBC Bay Area that that theory, at this point, is just "one opinion."
Spokesman Brian Haines also pinpointed the origin of the fire to one location: The Jawbone Ridge in Tuolumne County, which sits on Groveland Ranger District land, at the point where the Clavey River and the Tuolumne Wild and Scenic River meet up. That spot, he said, is the focus of the investigation.
California Fish and Game Lt. John Nores said that state wardens have been to that region several times on illegal marijuana grow "eradication and reclamation" missions. In the last five years, wardens busted up grow operations in the nearby Sequoia National Forest, south of the Rim Fire, and El Dorado National Forest, to the north (pictured to the right.)
Growers set up camp, including stoves and cook sites, within inches of dry grass within the last five years, said Fish and Game Lt. Pat Foy.
As of Monday, the Rim Fire remained the 4th largest wildfire in California's history, edging out a 222,777-acre fire that burned in Ventura County in 1932. The third largest fire is now the Zaca fire in Santa Barbara, which burned more than 240,000 acres in July 2007.
Despite the containment, a total of 5,500 structures still remained threatened, and so far, 111 buildings were damaged - 11 of them were homes, despite earlier reports that 31 homes had burned.
Check out an interactive map via Esri.com.