Spring Mountain District AVA
Climate: Similar to Mt. Veeder AVA, with cool weather prevailing and smaller
diurnal changes. Fairly cool nights and higher elevations help maintain good
acidity.
Elevation: 600 to 2200 ft (184 to 675m)
Rainfall: 40 to 50 inches (125cm) annually
Soils: Primarily sedimentary; weathered sandstone/shale, loamy and friable in
texture. Drainage is high, fertility low.
Principal varieties & characteristics: Cabernet Sauvignon, Merlot, Zinfandel: Powerful, firm, blackberry-currant flavors and often richly tannic, with excellent acidity for aging. Chardonnay, Viognier: Sinewy, firm and not as fruity as those of the valley floor, revealing more citrus and stone fruit flavors.
Stags Leap District AVA
Climate: Moderately warm, with afternoon marine winds acting as
an 'air-conditioner' to cool the warmer air radiating off the
bare rocks of Stags leap itself and the surrounding hillsides.
This AVA is often up to 10°F warmer than in Yountville AVA.
Mid-summer temperatures can reach 100°F, but more regularly
are in mid-90 range (32-34°C).
Elevation: 66 to 400 ft. (20 to 123 m)
Rainfall: 30 inches (75cm) annually
Soils: Volcanic gravel-loams on the floor of the valley, with rocky
hillsides, and low to moderate fertility due to hard clay bedrock
subsoils 2 to 6 feet down.
Principal varieties & characteristics: Cabernet Sauvignon, Merlot, Sangiovese: Distinguished by lush, velvety textures and fine perfumed cherry and red berry flavors, supported by soft tannins. Chardonnay, Sauvignon Blanc: Round and ripe, especially Sauvignon Blanc, yet retain excellent citrus and apple flavors.
Wild Horse Valley AVA
Climate: A warmer area well to the east of Napa Valley proper,
but still moderated by both altitude and prevailing winds coming
off Suisun Bay to the Southeast.
Elevation: Wild Horse Valley 400 to 1500 ft. (123 to 460 m)
Rainfall: 35 inches (94 cm) annually
Soils: Volcanic in origin, with basaltic red color, shallow with
limited water retention, so irrigation is often essential.
Principal varieties & characteristics: Cabernet Sauvignon, Sangiovese: Bright berry and cherry fruit, and more acidity than wines from Stags Leap District. Chardonnay: Crisp, flora, aromatic, with distinctive pear-mineral flavors and bright acidity.
Yountville
Climate: Moderate, with definite cool marine influence and fog
contributing to cool summer mornings and the marine breeze keeping
afternoons more comfortable than further up valley. Mid-summer
peak temperatures may reach 90°F (31°C), with noticeable
diurnal fluctuation to the mid-50°F range (13°C).
Elevation: 20 to 200 ft (6 to 61m)
Rainfall: 32 inches (80 cm) annually
Soils: Principally gravelly silt loams, sedimentary in origin,
and gravelly alluvial soils with rock, moderately fertile.
Principal varieties & characteristics:
Cabernet Sauvignon, Merlot: Yountville favors Cabernet and Merlot
with ripe, violety aromas and rich, but supple flavors and firm
tannins.