Dunnigan Hills, encompassing 89,000 acres of gently rolling hills in northwest Yolo County, has a Mediterranean style climate. These climactic conditions, combined with wonderful air-drainage, make the appellation less frost prone in early spring and favor the grapes with cooler summer days than the rest of Sacramento Valley. However, it’s important to note that days are still very hot here.

Canadian-owned R. H. Phillips, the AVA’s pioneering winery, has a 1,300-acre vineyard and a state of the art winemaking facility. The winery is dedicated to continuing research to preserve the quality of fruit during harvest and fermentation. All wines made at R.H. Phillips are cold fermented and many of the grapes are actually harvested at night to minimize time in the hot sun and oxidation. In addition to the very successful classic French varietals, considerable work is also being done with southern Rhone varietals, which seem to be gaining substantial recognition.