Howell Mountain
The Howell Mountain AVA encompasses a small zone on the eponymous mountain on the east side of Napa Valley, not for from the city of Saint Helena. The appellation begins at the 1400 foot mark, with some vineyards situated as high as 2400 feet; as the growers here like to point out, these elevations are above the fog line. Temperatures here are warmer at night and cooler during the day than the valley floor, while there is double the rainfall of the valley floor; soils - rich in iron along with volcanic ash - are rocky and drain well. Given these conditions, yields are rather small, resulting in very compact, powerful wines.

Cabernet Sauvignon is the most famous wine from Howell Mountain; of all the mountain districts of Napa Valley, the Cabernets from Howell Mountain are among the most intense and longest-lived. Interestingly, cool air at these elevations slows down ripening; harvest in some years is not until early November! Be prepared to pay upwards of $100 a bottle for top examples of Howell Mountain Cabernet Sauvignon. (Wine/Appellations)