California
If 50 American states produce wine, Californian production alone represents approximately 85% of the country's production, making this state the 4th largest producer in the world behind Italy, France and Spain. The climate is strongly influenced by the Pacific Ocean which at this latitude is a cold ocean. The wine-growing regions located near the Pacific have an oceanic climate becoming Mediterranean the further inland you go from the ocean and it becomes more continental near the Sierra Nevada. Bays and openings to the sea, such as San Pablo Bay, act as thermal regulators on viticulture, particularly in Napa and Sonoma Valley.
Santa Cruz Mountains
Vineyards dot the valleys and ridges of this coastal subregion just south of San Francisco. Microclimates are difficult to generalize about, and vineyards are often separated by acres of forests and meadows (not to mention entire towns!), but this area is nevertheless known for its cooler climate, ideal for Pinot Noir. This climate makes it possible to obtain wines with a less mature profile, less powerful and with more finesse.