The Eagle Peak, Mendocino County AVA is 26,260 acres in composition with boundaries drawn that reduce both Mendocino AVA by 1,900 acres and Redwood Valley AVA by 1,430 acres. It lies completely within Mendocino County.

At 2699 feet Eagle Peak lies within the Laughlin Range of the California Coastal Range. Eagle Peak Mendocino County as proposed ranges from 1,100 to 3,320 feet with rolling and steeply sloping terrain. It is located approximately 125 miles north of San Francisco, in a climatic transition zone between the cooler Pacific coast and the hotter inland valleys. Eagle Peak is just south of Ridge, California.

Influenced by cool, moist air from the Pacific Ocean, which moderates daily temperatures and seasonal temperature variations, an average of only 22 days per year with temperatures over 90 degrees Fahrenheit (F)typifies the growing area. Only 25 degrees separate the coldest day from the warmest day in the AVA. The steep upland nature of the topography influence evening inversion with cool air dropping into the valley and diurnal shifts are a mere 20.6 degrees on average. This is said to influence and aid late season ripening.

The Big River airflow corridor also plays a role in the summer winds that are common throughout the proposed Eagle Peak Mendocino County viticultural area. During the summer, hot air rises from the Redwood, Potter, and Ukiah Valleys east and south of the proposed viticultural area, creating low pressure at ground level. The low pressure pulls cooler marine air from the Pacific Ocean through the Big River airflow corridor and into the proposed Eagle Peak Mendocino County viticultural area.

Soils within Eagle Peak Mendocino County viticultural area include profoundly low water-holding capacity, shallow rooting depths, and high erosion potential, due to the composition of the soil and the steep slopes. The soils are classified as upland under grass and oaks, or under forest (fog-influenced). Primary soil associations are the Yorkville-Yorktree-Squawrock and Ornbaun-Zeni-Yellowhound associations. The soils retain enough water to allow the vines to come out of dormancy in the spring and make it through the “grand growth stage” without irrigation, but irrigation is required for the rest of the growing season.