field contains The Geysers, a steam field which powers a network of the world’s most productive geothermal power plants. There are numerous small faults present in the south end of the lake as well as many volcanoes, ranging in age from 10,000 to 2.1 million years, the largest being Mount Konocti, sitting at the middle of the lake's south shore. There have been no eruptions from the Clear Lake Volcanic Field for thousands of years, but there are indicators currently being monitored that suggest there is the potential for future eruptions. These indicators include volcanic-type earthquakes, hot spring activity and seepage of volcanic gas. Weather It is not uncommon for temperatures in the summer to go into the triple digits or below freezing in the winter. Occasional summer thunderstorms occur but are not common. Snow can fall to lake level but accumulation is rare. Snow on the surrounding mountains is common. The average high temperature is in summer, and the average low is in winter. Normally, July is the hottest month and December the coldest. December and January are the wettest months, with an average of of rain per month, respectively. Recreation With over of shoreline, Clear Lake is a popular spot for water sports enthusiasts. According to the California Water Boards, Clear Lake sees 15,000 recreational boaters per year. There are 11 free boat launch ramps around the lake that are open to the public. Individuals may rent boats and personal water craft from many businesses around the lake. Clear Lake is sometimes called the "Bass Capital of the West." Largemouth bass, which are farmed and planted in the lake by California Department of Fish and Wildlife, crappie, catfish, bluegill, and rainbow trout can be found in the county's lakes. Fishing boats can be rented, and many stores and facilities around the lake specialize in fishing equipment. Numerous fishing tournaments and derbies are held through the year. In 2016, Clear Lake was ranked by Bassmaster Magazine as the #3 best bass lake in the United States and the #1 best bass lake on the West Coast. Area wineries with tasting rooms include Guenoc and Langtry Estate Vineyards and Winery, Steele Wines, Brassfield Wines, Vigilance Wines, Six Sigma Winery, and Wildhurst Vineyards among others. All boaters entering Lake County are warned that Dreissenid mussels, otherwise known as quagga and zebra mussels are a great threat to Clear Lake. By law,