The Temecula Valley AVA (American Viticultural Area) is the largest designated wine region in the South Coast wine region of California. The name Temecula is reportedly a local Native American term for 'the land of sunshine and mist’, and whether faithful or not, this translation accurately describes the climate in the Temecula Valley.
As the valley heats up during the morning, warm air rises upwards and further inland, creating a pressure differential. Natural convection draws cool Pacific Ocean air into the valley through gaps in the Santa Ana Mountains (the coastal ranges which separate Orange County from Riverside County). These 'Santa Ana winds' can become quite strong, and in 2007 blew a minor scrub fire up into a major wildfire which scorched much of the Temecula Valley area. A similar climatic effect blows through the Chino Hills 50 miles (80km) to the north, cooling the Cucamonga Valley AVA.
Temecula lies 22 miles (35km) east of the Pacific coast, so the valley enjoys a relatively strong maritime influence. As cool, moist air rolls up the valley, it condenses to form mist and refreshes the local vineyards, preparing them for the hot southern California afternoon. This mist is lighter than the fog found in the lower-lying terroirs of Napa and Sonoma, and reflects sunshine rather than deflecting it.
To further reinforce the interplay between light and water in Temecula, the two gaps in the Santa Ana Mountains through which the cooling air currents blow are known as the Rainbow and De Luz gaps. Luz means 'light' in Spanish, but the rainbow connection is not as obvious: it is the name of a local landowner in the 1880s, Mr J P M Rainbow.
Were the Santa Anas slightly higher or the valley slightly further from the coast, Temecula would be significantly hotter and drier than it is, making quality viticulture more of a challenge. Very few places on Temecula's latitude (33 degrees north) support quality viticulture: Lebanon and Israel are the only remotely obvious examples. However, the Temecula Valley terroir is well suited to grape growing, with free-draining, granite soils supporting the vines. The higher elevation sees most vineyards planted at 1500ft (457m) above sea level, which contributes to cooler nights and higher acidity in the grapes. Irrigation is necessary in this very dry region, allowing growers to control yields and grape quality.
Almost half of all vines in the Temecula Valley were destroyed by Pierce’s Disease in the 1990s, but ultimately this seems to have worked in the region's favor. Not only are more disease-resistant varieties being planted, but a new range of quality wines has emerged. In the past, the region was mostly known for its value-for-money, delicate, low-alcohol white wines. Post-Pierce’s Disease plantings focus firmly on the more lucrative, big Mediterranean reds.
Temecula Valley Tempranillo wines are notable for their complex aromas of plums and berries. Sangiovese wines from the AVA boast fat, ripe tannins and flavors decidedly riper than their Italian counterparts. Syrah has recently won the region many accolades for its round, fleshy style and generous, full flavors. Cabernet Franc has emerged as the star of the Bordeaux varieties and is fast earning a reputation for producing elegant, aromatic styles full of complex flavors.