Timber (litter and understory)

Light logging slash

Brush (2 feet)

The fire continued to be active throughout the night. Minimal growth occurred in Div I and Div N, with no additional growth in any other divisions. Poor overnight humidity recovery and warm temperatures allowed interior islands and green stringers to retain heat that will pose potential threats during the heat of the day. Minor spot fires were picked up easily, with interior single tree torching taking place.

WEST ZONE: Provide for the life safety of citizens and emergency responders. Implement structure and critical infrastructure defense. Construct control lines and take advantage of targets of opportunity as allowed by fire behavior and resource limitations. Improve and hold established control lines. Identify and establish contingency lines. Tactical patrol of perimeter contained. Aggressive mop-up, backhaul of hose, and tactical patrol will continue in DIV A and D. Contingency Group will continue work in Branch 10. In DIV N and P, crews will continue to strengthen and improve control lines, and provide structure defense in communities in the Kirkwood area. Direct line construction will continue in DIV I. MIST tactics will be used in the Desolation Wilderness. Fire Suppression Repair continues to evaluate repair needs and will implement the Incident's Fire Suppression Repair Plan.

EAST ZONE: From Highway 89 west to Scout Peak, crews will remain engaged in strengthening direct containment lines with aggressive mop up to reduce the threat to structures. In the Christmas Valley area, resources will continue to patrol and mop up as necessary and mitigate hazards in preparation for repopulation. On the northeastern side of the fire, resources will strengthen existing fireline and continue to use direct tactics. On the southern flank of the eastern finger of the fire, a combination of direct hand and dozer line is nearing completion to keep fire from moving to the south and east. In the northwest part of the zone in the area of Upper and Lower Echo lakes, crews will continue to construct direct fireline toward Ralston Lake. In the Lower and Upper Echo Lake areas, structure prep and line construction operations are complete. In the Caples Lake area crews will hold line, mop up, and extend fireline toward the zone break. Wildland fire modules and a heli-rappel crew have been inserted into the Desolation Wilderness to contain the northwestern corner of the East Zone with the support of aircraft. Additional wildland fire modules are on order for this area. A contingency group is nearing completion on building contingency lines to the northeast of the fire in the event of fire crossing primary containment lines. Mastication and chipping are occurring on road systems south of the east zone of the fire. Crews are also masticating roads in the Fallen Leaf Lake area for contingency purposes.

The Governor of California declared a State of Emergency for El Dorado County on August 17, 2021, due to the Caldor Fire.

The Eldorado National Forest is closed from August 17, 2021, through September 30, 2021. (Forest Order No. 03-21-14) To better provide public and firefighter safety due to the ongoing California wildfire crisis, USDA Forest Service Pacific Southwest Region announced a temporary closure of all National Forests in California from Aug. 31, 2021 through September 17, 2021.

CAL FIRE IMT-2 and NIMO-2 are in command of the West Zone and CIIMT-4 is in command of the East Zone. Fuels reduction projects that have been implemented around the community of South Lake Tahoe have been highly effective in providing opportunities for resources to successfully suppress fire.

WEST ZONE: A fire weather watch has been issued from Thursday afternoon through Friday afternoon for isolated thunderstorms, dry conditions, and increasing winds Thursday night through Friday. Winds could reach 20 to 30 mph with ridge top winds around 40 mph early Friday morning through Friday afternoon.

EAST ZONE: Observations: Strong inversions formed overnight with poor humidity recoveries above 6800', only reaching 25 to 35% along the mid-slopes and ridgelines. Good recoveries occurred in the lower valleys with temperatures in the upper 30's and low 40's. Southwest ridge winds in the evening became lighter and shifted to the south remaining variable with downslope, terrain-driven winds, over the rest of the fire area. Thursday Forecast: A major change in the weather is expected Thursday into Friday as a cold front moves through the region. A Fire Weather Watch is in effect for dry lightning and gusty southwest winds Thursday evening through Friday evening. Chances for thunderstorms exist beginning Thursday and persisting through Friday evening with the best chance of storms Friday morning over the Caldor Fire. Winds will start to pick up Thursday evening along the ridgetops with very strong winds expected on Friday. Winds could gust 50+ mph along the ridgetops with winds 15-25 mph gusting up to 35 mph in the lower elevations.