Petaluma Gap AVA — What Everyone Should Know

The Petaluma Gap AVA celebrates its second anniversary on December 9. Unlike some AVAs which are established, but fail to gain traction commercially, the Petaluma Gap AVA was embraced immediately and is sought after by consumers and wine professionals.

There are several, clear reasons for this success:

The Petaluma Gap AVA has a unique and easily understood point of difference—cold ocean winds and blanketing fog pour through its namesake break in the Coast Range.
The physical Petaluma Gap has long been referenced as an important moderating influence on temperatures in the Russian River Valley AVA and parts of the Sonoma Coast AVA.
That cooling effect is even more clearly represented in the Petaluma Gap AVA and its juicy wines.
Wines coming from the AVA are very good
Many of its vineyards have been rated highly for more than a decade and their names appear as designated vineyards on bottles from top wineries.
There’s a marketing advantage to being, in part, a subdivision of the popular Sonoma Coast AVA, rather than a wholly new zone.

Where is the Petaluma Gap AVA?

The AVA overlaps the border between Sonoma and Marin counties. It includes the southwestern portion of the Sonoma Coast AVA. Part of the northern Petaluma Gap AVA boundary is the Russian River Valley AVA’s southern boundary.

The AVA’s largest town is Petaluma. Bodega Bay, Tomales, and Cotati are also within it. Novato, in Marin County, is about 2 miles south of the boundary. Highways 101 and 116 both run through the AVA’s eastern side.

Map courtesy of Petaluma Gap Winegrowers Alliance

Petaluma Gap AVA Climate

The Petaluma Gap AVA has a warm (as opposed to hot) summer, Mediterranean climate. Rainfall comes almost exclusively during winter. Depending on vineyard-specific variables, some growers can dry farm, while others need to irrigate.

The Pacific Ocean influence keeps the region relatively cool all day. Even during the growing season, the average high temperature is just 77° and the median 63°. Biologically effective degree-days are 1,690. That’s about 20 less than Green Valley of Russian River Valley AVA, previously considered Sonoma County’s coolest zone on average.

The Central Valley’s great, afternoon heat creates low-pressure zones. Cooler air rushes inland from the west to compensate. The air that’s sucked in from offshore is thoroughly chilled by the sea. Upwelling of deep, frigid water near the gap makes the ocean surface there particularly cold.

Since the Petaluma Gap AVA is closest to the source of the cold wind, it is cooled more dramatically than it’s neighboring growing regions. Carneros, just east of the southern Petaluma Gap AVA is predominantly cooled by the same breezes, but the wind has warmed somewhat by the time it gets there. The Russian River Valley also benefits. And fog coming through the gap can reach as far north as Geyserville, but there’s less of it and that area doesn’t get any of the chilling wind.

High up in the Cline Catapult Ranch Vineyard and looking west from across the AVA, toward the ocean.

AVA Details

Latitude: 34.54°

Altitude: 10’ to 1,885′, average 370’

Climate:

warm-summer Mediterranean
2,805 degree days – Winkler-Amerine Region II
1,690 biologically effective degree days

Annual Rainfall: 37 inches

Soils: various; predominantly clay and clay loam of volcanic origin. Some sites are quite rocky, others sandy

Total Acres: 202,476

Vineyard Acres: 4,000

Number of Vineyards:

Median Vineyard Size: 19 acres

Primary Grape Varieties: Pinot Noir (75%), Chardonnay (13%), and Syrah (12%)

Primary Viticultural Challenge: Late ripening

AVA Organization: Petaluma Gap Winegrowers Alliance

Wineries You Can Visit Within the AVA (7)

Adobe Road

Azari Vineyards

Karah Estate

Kastania Vineyards (temporarily closed)

Keller Estate

McEvoy Ranch

Stubbs Vineyard

Key Vineyards

Armagh

Clary Ranch – Grand Vent

Cline Cellars

Clouds Rest

Gap’s Crown

Griffin’s Lair Vineyards

Keller Estate – La Cruz

Kendric Vineyards

McEvoy Ranch Vineyards

Pfendler

Sangiacomo – Lakeville

Sangiacomo – Roberts Road

Silverado Sonoma – Cabral

Silverado Sonoma – Rodger’s Creek

Stage Gulch

Sun Chase Vineyard

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