In United States, the imbalance is obvious concerning geographical distribution of the vineyard. California accounts for more than   80% of the total production.

California. Its enormous vineyards can be divided into 3 wine-producing area :

- In the north of San Francisco, famous  vineyards of  Napa Valley, Sonoma, Los Carneros  and Mendocino, settle in valleys that groove the coastal range of mountains. Napa Valley (Napanet, The Napa Valley), the most known of them, is the center of the California fine wines : many red wines of Cabernet Sauvignon and white wines of Chardonnay. Robert Mondavi, renowned winery, elaborates, beside its famous "Cabernet", very fine white wines of Chardonnay and Sauvignon. Others exceptional wineries : Beaulieu Vineyard, Beringer Vineyard, Clos du Val Winery, Diamond Chandon, Grgich Hills, Hess Collection, Joseph Phelps Vineyards, Schramsberg, Silver Oak Cellars, Sterling Vineyard. 
The Sonoma valley (Sonoma County Virtual Visit) provides wines comparable enough, elaborated by the prestigious wineries : Carmenet Winery, Clos du Bois, DeLoach Vineyards, Dry Creek Vineyard, Geyser Peak Winery.
Los Carneros, one of the most important Californian wine-producing areas, whose name is associated with a genius of André Tchelistcheff.  Delicate Pinot Noir, nervous and alive Chardonnay, the Merlot and the Cabernet have all a European style, even if vineyards of which they are made do not resemble   anything in Europe. The best wineries : Buena Vista Carneros Winery, Carneros Creek Winery, Domaine Carneros.
Despite its northern location, the region of Mendocino possesses an honorable and diversified production. The best wineries : McDowell Valley Vineyards, Navarro Vineyards.

- In the south of San Francisco, the central Coast, series of vineyards follow the Pacific littoral. The vineyards of Santa Cruz are in development. Some of these vineyards, such these of Bonny Doon, Mount Eden, David Bruce and of course Ridge (the most famous of the wineries dispersed around the San Francisco bay) produce remarkable wines.
The most important sector is the vast vineyard  of Salinas Valley, in the rear county of Monterey : it is the domain of the " great " of the Californian vineyard (Paul Masson, Almaden), which align impressive range of wines (Zinfandel, Ruby Cabernet, Chardonnay.. .).
More to the south, the region of Santa Barbara, favored by a climate fresh enough, succeeds a production of quality " Santa Barbara Winery " with the  northern grape varieties (Riesling, Chardonnay, Pinot Noir)

- In the south of Sacramento, parallel to the before zone, is the San Joaquin valley. This immense vineyard that descends until Bakersfield is characterized by a hot continental climate ; it is the Californian great reservoir of wines from more current quality, harvested and  drawn up to industrial scale by powerful groups (Gallo, United Vintners)
There other wine producing areas in California : Livermore valley, to the south-east of San Francisco bay (excellent white wines from Sauvignon, Semillon and Chardonnay), San Pasqual valley to the north-east of San Diego, the small vineyard of San Bernardino to the east of Los Angeles.

State of New York. It is the second largest vineyard area of United States. It is characterized by the enormous difference in production from those in California. Its essential particularity is cohabitation of grape varieties of vinifera and labrusca ( grapes of type Concord), as well as hybrids Franco - Americans (Baco, Aurora).
The best vineyards are situated in the region of Finger Lakes, where some European grapes (Riesling, Chardonnay) give very suitable results, and, to a lesser extent, in the Hudson valley (excellent wines from Benmarl), as well as to Long Island (Hargrave Vineyard, Lenz Vineyard and Winery, Palmer Vineyard). Of course, it is necessary  to mention too an industrial style production with variable qualities.

States of Oregon and Washington. The size of vineyards is smaller and more recent.
- Oregon wines (Oregon Wine) are produced to the south of Portland, in the Willamette valley (Rex Hill Winery, Sokol Blosser Winery)
- These of the state of Washington are harvested more in the interior of the region, in the Yakima valley (Hogue Cellars, Chateau Ste Michelle)
In these two vineyards the acclimatization of Vitis vinifera, especially through its white grape varieties (Chardonnay, Sémillon, Riesling) has good success, with wines whose quality is regular.

To know more about American wines, visit these three web site : Wines on the Internet, Wine.com, Smart Wine.