Climate: Cool, with prevailing marine winds from the San Pablo Bay and through the Petaluma Gap to the west. High temperatures during summer rarely exceed 80°F (27°C).
Soils: Clay dominated, very shallow in general, with more loam and hillside alluvials in the northern section. Yields typically are restrained by the hard claypan subsoil, which prevents deep-rooting.
Principal varieties & characteristics: Chardonnay: minerally pear-apple and spice flavors. Merlot: sinewy and lightly herbal, with fine tannins and sleek structure. Pinot Noir: ripe cherry-cinnamon spice flavors with earthy notes.
Principle Wineries: