Temecula Valley - A Unique Micro-Climate Temecula is located 500 miles south of San Francisco, resulting in a slightly higher angle to the sun and greater solar intensity. A look at the native chaparral shows that Temecula is in a relatively low rainfall region. These two factors create an early growing season that generally runs from March through September. Rains, however, rarely interrupt the harvest season, - an important factor in wine quality.
The vineyards are irrigated from huge underground aquifers, which are refilled by rainfall from the surrounding mountains. Perhaps more important are significant cooling factors that effect the flavor development of the grapes. As the sun warms the inland valleys east of Temecula, the air rises, forming a low-pressure area. The colder, much heavier air from the Pacific Ocean, just 22 miles from Temecula, is then drawn inland. The Coastal Mountain Range allows the colder air to pass inland through gaps and low spots. The Rainbow Gap and the Santa Margarita Gap are two of these low places in the mountains - and just beyond them lay Temecula Valley. The cool air flowing inland moderates the daytime temperatures and helps to create a pattern of warm sunny days and cool nights, ideal conditions for the best wine grapes.
At 1500 feet above sea level, the Temecula Valley offers an ideal location for growing premium wine grapes. The perfect balance of geography, microclimate and well-drained soil come together to create just the right environment for exquisitely handcrafted wines.
The Lapse-Effect Cool Air
The second meteorological factor affecting the Valley's climate is the "lapse rate." It involves the altitude of the vineyard land and the height of the surrounding mountains. Temecula vineyards are located 1,400 to 1,600 feet above sea level. The surrounding mountains average 2,000 to nearly 11,000 feet elevation. These high elevations mean cooler air - a temperature drop of three degrees for every 1,000 feet of altitude gain.
The heavy cold air that collects between the high peaks during the night drains off the heights much like water, joining cold moist air from the Santa Margarita River Channel to meander through the Temecula Valley, creating a double cooling effect. As a result, nighttime lows in and around Temecula are very cool. The cool nighttime temperatures are critical in developing high quality grapes.
Ideal Soils Granite and Well Drained
Temecula Valley soils are another significant influence on wine quality. The soils are created from decomposing granitic materials and are excellent for growing high quality grapes. Grapevines require well-drained soils; they don't like their roots to be constantly wet. The granitic soils permit the water to drain through quite easily. Granitic soils are a light sandy loam. These soils contribute to clean, pure varietal flavors without odd or herbaceous flavors that wetter soil may cause.