California's Napa Valley is perhaps the best known of North America's wine regions with some pretty iconic wines to be found there. The napa has quite diverse terrors and thus it is a patchwork of grape varieties with the vineyards of individual wineries scattered throughout the region. Indeed, many wineries don't own a vine and simply buy in fruit for their needs. The wines tend to be high priced and as much of the production drunk locally, little appears in the export market and when it does, make sure your credit card has plenty of head room! Despite the love of Cabernet by all and sundry there, for us, Zinfandel which has made its home there, is well worth searching out.
Not far from the Napa, Sonoma County offers more affordable offerings and Chardonnay and more recently Pinot Noir are faring well especially in areas such as the Russian River Valley. Rockpile and Dry Creek Valley are also making good wine especially from Zinfandel.
If Napa is famous for its small boutique and expensive production, the Central Valley is another thing entirely with vast quantities of light, fairly characterless wines produced. In fact everything grows for fun here, fruit, nuts, you name it they can grow it. More wine is produced here than in Chile!
In the pacific North-West, Washington, Oregon and Idaho are now making some excellent wines and perhaps the most famous are the Pinot Noirs from Oregon. The Willamette Valley is the most sought-after producing part thanks to its climate and the Pinots here can often have bolder fruit than those from Burgundy. As it's important to get the harvest in before the rains arrive in autumn, different clones to Burgundy are used and thus the wines deliver other nuances that set them apart from the European benchmarks.
New York State now produces some interesting offerings and in areas such as Long Island that have an Atlantic influence, some finesse and elegance can be seen in the wines even when grown from the Bordeaux varieties. The bodies of water in the Finger Lakes area also play their part and some interesting wines are being made from aromatic varieties such as Riesling and Gewürztraminer.