Clear Lake AVA

Clear Lake is an American Viticultural Area (AVA) located entirely within Lake County, California. It was established on June 7, 1984 by Bureau of Alcohol, Tobacco and Firearms (ATF), Treasury after reviewing the petition submitted by three of the grape-growers and winery owners located in an area surrounding the watershed of Clear Lake in southwestern Lake County proposing the viticultural area named "Clear Lake."^[3]
The AVA is located between the Mayacamas Mountains to the southwest and the Mendocino National Forest to the northeast. It extends to the southeast to just north of the Guenoc Valley viticultural area also in Lake County. Clear Lake viticultural area lies entirely within the boundaries of a multi-county North Coast viticultural area.^[1]
Half of viticultural area contains Clear Lake, the largest body of freshwater in the state of California, and the namesake for the county and town. Some localities that also use the name Clear Lake in their heritage are Clearlake Oaks, Clearlake Park, Clearlake Highlands and Clear Lake State Park. United States Geographical Survey maps document this information.^[1]
The moderating influence of the lake on the surrounding area results in a climate with less diurnal variation in temperature than surrounding areas where elevations range from 1,300 feet (400 m) to well over 3,000 feet (910 m).^[1][5] Clear Lake AVA is one of the coolest climates in California, which has led to success with grape varietals like Sauvignon blanc.

Clear Lake with surrounding terrain

Clear Lake

Wine region
Type	American Viticultural Area
Year established	1984[1]
Country	United States
Part of	Lake County
Other regions in Lake County	Guenoc Valley AVA, Long Valley-Lake County AVA
Sub-regions	Big Valley District-Lake County AVA, High Valley AVA, Kelsey Bench-Lake County AVA, Red Hills Lake County AVA, Upper Lake Valley AVA[2]
Climate region	Region II-III[3]
Heat units	2,930-3,260 GDD[3]
Precipitation (annual average)	37 in (940 mm)[1]
Soil conditions	Bright-red volcanic, uniform sandy loam and clay loam soil[3][4]
Total area	168,960 acres (264 sq mi)[1]
Size of planted vineyards	5,000 acres (2,000 ha)[5]
Grapes produced	Cabernet Franc, Cabernet Sauvignon, Chardonnay, Merlot, Muscat, Petite Sirah, Pinot gris, Riesling, Sauvignon blanc, Syrah, Viognier
No. of wineries	13