Like Napa Valley, Sonoma Valley is cooler in its southern end and grows warmer as you travel north through the region. But Sonoma Mountain blocks the cool Pacific breezes and fogs that are known for blanketing many parts of Sonoma County, keeping the region relatively warm and dry. Cool breezes sneak in from San Pablo Bay to the south and from the Santa Rosa plain to the north. Many distintictive terroirs can be found throughout the region, all of which are awaiting AVA approval. The Sonoma Mountain and Los Carneros AVAs can both be found within Sonoma Valley.