The Coquimbo region of Chile touches the Atacama desert on the northern border and the Aconcagua wine region on the southern border. It comprises three subregions: Valle del Elqui, Valle del Limarí, and Valle del Choapa. The production focus of this region remains on table grapes and pisco but more and more producers are turning to fine wine. The entire region is arid and reliant on irrigation using water from the Andes snowmelt. The arid climate means nearly unlimited clear days and nights. The highly regarded astronomical observatories in the Elqui are located here due to the the clear nights.
The northernmost subregion is Valle del Elqui, which follows the Elqui river valley up from the coast. The valley is fully open to the Pacific and experiences an influx of cool air each afternoon. The valley averages 2.75 inches (70 mm) of rain per year, which means the skies are almost always clear and disease pressure is very low. The proximity of the Andes and the desert climate offer a dramatic diurnal shift from warm days to cold nights. The growing season is much longer than it should be for thirty degrees south latitude.
The arid Valle del Limarí is in the narrowest section of Chile where the Andes are very close to the sea. The valley opens to the Pacific and pulls in the maritime fog in the mornings, but rainfall is scarce at 3.7 inches (94 mm) per year. The brilliant sunny days burn off the fog and would surely make the region hot, but the updraft off the land pulls in cooling sea breezes in the afternoon. The Pacific influence makes this region similar to the Santa Maria Valley in California, and to the Chilean regions of Valle de Leyda and Valle de Casablanca. The soils are dominated by calcareous material, which is conducive for the production of Chardonnay.
Valley del Choapa is an emerging wine region and one of the newest in Chile. It benefits from elevation and Pacific cool air. The subregion has a very bright future for fine wine.