Im Osten von Napa Valley in den Vaca-Bergen liegt die AVA (American Viticultural Area) HOWELL MOUNTAIN, eine Region, die wegen ihres einzigartigen Mikroklimas als erste Unterregion im Napa Valley festgelegt wurde.
Elin McCoy schreibt im DECANTER (März 2019):
"HOWELL MOUNTAIN: 10 names to know
O’Shaughnessy Estate Winery
Founded by Betty O’Shaughnessy in 1996, this 49ha estate is unique in growing eight Bordeaux red varieties, including St-Macaire, Gros Verdot and Carmenère. Sean Capiaux crafts a luxurious, complex Cabernet blend in a stunning stone and glass winery where music soothes wines ageing in barrels.
Turley Wine Cellars
Turley Wine Cellars acquired its own Howell Mountain vineyard, whose grapes go into a special appellation-designated bottling, as have many other valley floor wineries including Abreu, Dana Estates and Heitz Cellar. Turley makes some of the AVA’s most distinctive Zinfandels from its Rattlesnake Ridge (at 732m one of the AVA’s highest vineyards) and Dragon Vineyard sites.
Howell Mountain at a glance
Area under vine 607ha
Elevation: 427m-726m Soil type Rocky volcanic ash (tufa) and red clay
Microclimate: Warm mornings, intense sunlight, cooler than the valley floor
Number of wineries: about 50
Number of growers 38
Grapes: White Sauvignon Blanc Red Cabernet Sauvignon, Cabernet Franc, Merlot, Petit Verdot, Malbec, Zinfandel, Petite Sirah, Syrah, St-Macaire "