Suisun Valley AVA length. The valley is approximately by , and contains about . More than of the valley is currently planted as vineyard, with more than twenty varieties of wine grapes represented, including Barbera, Cabernet Sauvignon, Chardonnay, French Colombard, Gamay (Valdiguie), Grenache, Merlot, Mouvedre, Muscat Canelli, Petite Sirah, Petite Verdot, Pinot Gris, Pinot Noir, Primitivo, Rousanne, Sauvignon Blanc, Sangiovese, Shiraz, Syrah, Viognier, Riesling, and Zinfandel. Suisun Valley has a semi-coastal Mediterranean climate with a cool wet season from November to April, followed by a warm dry season. Moist winds blow inland from San Pablo Bay and Suisun Bay at the headwaters of
Peloursin Rif" (later Durif) by ampelographer Victor Pulliat in 1868. Durif later made its way to California where it was eventually named Petite Sirah. In the late 20th century University of California, Davis researchers led by Dr. Carole Meredith discovered that some of the California plantings of Petite Sirah were, in fact Peloursin, and that Peloursin had a parent-offspring relationship with Durif that likely sprung from a crossing with Syrah. Peloursin is a vigorous grapevine capable of producing high yields and excessive foliage if not kept in check with winter pruning and summertime leaf pulling. The variety tends to be a