The Dry Creek Valley AVA is in Northern Sonoma County, California, to the west of the Russian river. The valley is generally warm but contains many microclimates, and parts of the AVA are close enough to the coast for the Pacific Ocean to influence the wines. Dry Creek Valley's neighbors are the prestigious AVAs of Russian River Valley, Alexander Valley and Chalk Hill. The Knights and Green valleys are just across the Russian river.
The southern part of the region, near the Russian river, is quite foggy and therefore cooler, making it better suited to Chardonnay and Sauvignon Blanc. Further north, where it is warmer, the big reds – Cabernet Sauvignon, Zinfandel and Syrah – are grown. The climate in Dry Creek Valley particularly suits Zinfandel, which is produced in many different styles depending on where it was planted. The soil is porous and sandy in many areas. The term 'Dry Creek conglomerate' describes the free-draining, gravelly soils found in the mountain lowlands: in vineyards of this area, some of the highest-quality grapes are grown.
Dry Creek Valley features various disparities that are central to the AVA's character. To start, how many wine regions specialise in two varieties as disparate as Zinfandel and Sauvignon Blanc? Also highly visible is the juxtaposition of the area's many small-scale boutique wineries with the gargantuan Gallo Family winery just outside Healdsburg. One of the United States' largest wine producers, Gallo's purchasing power extends over many thousands of acres of vineyard, here in Dry Creek and in AVAs the length and breadth of California. Gallo's choice of Dry Creek as a location had little to do with the AVA's reputation, however, and everything to do with the practicalities of being located in Healdsburg, at the center of Northern Sonoma: Route 101 runs along the western edge of Healdsburg, connecting it with Cloverdale in the north and Santa Rosa, Petaluma and ultimately San Francisco in the south.