The Rim Fire overnight continued to spread toward Yosemite National Park and, to a lesser extent, communities along Highway 108, covering an area of about 149,780 acres, making it larger than 1987's Stanislaus Complex Fire.
The fire as of this morning was 15 percent contained - a two-fold improvement over the weekend.
It has destroyed at least 23 structures, threatens 4,500 others and has cost $20.1 million to fight.
Two huge firefighter staging areas have been set up - off Cherry Lake Road near Groveland, and at the West Side property in Tuolumne City. Some 3,678 firefighters and support personnel from around the state have been deployed, in addition to several aircraft.
The new acreage estimate, like earlier ones, is based on a flyover of the fire scene overnight. Infrared cameras take images of the fire and the size is calculated by computer, according to a spokesman with the Incident Command Team stationed off Cherry Lake Road, outside Groveland.
The Stanislaus Complex Fire, sparked by lightning storms, burned 145,980 acres and 28 structures in an area overlapping the Rim Fire. One firefighter was killed in that fire - heretofore the largest blaze in Tuolumne County since such records started being reliably kept in the early 1930s.
Sherri Brennan, who represents District 1 on the Tuolumne County Board of Supervisors, saw the parallels between the two - massive and out-of-control fire, fed by overgrown and exceptionally dry "fuels" like grass, scrub and trees - as she, her husband and friends Saturday cleared the family's cattle from a roughly 20,000-acre allotment off Cottonwood Road, east of Tuolumne City.
"We have to do in a week what usually takes a month," she explained of clearing the animals, accustomed to feeding in the forest from spring to fall.
She later admired Sierra Pacific Industries' bootstraps firebreak-clearing operation down the road, where the company was cutting lines with bulldozers to protect its stands of trees.
Similar government clearing operations were taking place Saturday near homes where Buchanan Mine Road becomes Cottonwood Road.
Homeowner David Smith watched the firefighting operation for two days - first as planes plastered the North Fork Stanislaus canyon walls with what's termed "fugitive" colored red-orange retardant, then as bulldozers cleared a fire break along a hillside so steep it'd be scary to hike down, let alone drive down.
Like many people, Smith, a plumber, said he had no plans to leave even though the area was under an evacuation "advisory." He worried his home would be vulnerable to looters.
Evacuations advisories were issued for the Tuolumne City area as well as Highway 108 communities stretching from Soulsbyville to Mi-Wuk Village late last week. As of this morning, they remain in effect. While the retardant lines and firebreaks have seriously hampered the fire's progress west toward the North Fork Tuolumne River, a serious danger is seen in the potential for "spotting" - when hot ash or flames touch off new fires yards or even miles away.
Access into Tuolumne City and the nearby areas of Ponderosa Hills and Sherwood Forest are restricted to residents only.
Most areas earlier threatened by the fire in Groveland - like most units of the Pine Mountain Lake subdivision outside town - are no longer under evacuation advisories or orders, lifted Saturday as the fire danger in the south county waned.
Only 16 to 18 homes remain under mandatory evacuation notice in Tuolumne County, on Clements Road, past the cattle guards.
At the still-hot southeast end of the fire, however, a mandatory evacuation order was issued by the Mariposa County Sheriff's Office on Sunday night for residences north of Old Yosemite Road (Forest Road 2S01). An evacuation warning was also issued for all residences north of Bull Creek Road (Forest Road 2S02), Bondurant Mine Road, Texas Hill Road, and Wampum Hill.
Much of the National Forest land abutting the evacuations areas is smoldering or has been reduced to ash. Hillsides formerly lined with pines and manzanita in the Tuolumne River canyon now look like dead coral reefs.
The burned forest areas -the entire the Groveland Ranger District and much of the Mi-Wok Ranger District - are closed to the public. People who enter those areas without permission while the order is in effect face fines of $5,000 and/or six months in jail. The order is effective until it's reversed by the Forest Service office in Sonora, which could be weeks or months from now.
The fire's eastern flank continues to creep into Yosemite National Park. It's burning hottest in the southeast, while in the northeast it has encountered heavy granite and less-forested areas.
Park officials over the weekend took extra precautions in protecting Yosemite's two groves of giant sequoia trees - clearing areas around the groves and setting up sprinklers in threatened areas.
The Rim Fire started Aug. 17 in the Clavey River canyon, about 5 miles west of the Lumsden Bridge.
The cause remains under investigation.