The Charles family has been working a piece of land in the Anderson Valley of California for generations. But in 2006, Bill and Nancy Charles, along with their daughter and son-in-law, Kristy Charles and Joe Webb, opened Foursight Wines and began to produce small lots of estate-grown Pinot Noir, Semillon, and Sauvignon Blanc.

The Anderson Valley, just outside of Boonville and just west of the famed Napa Valley, is one of the most unique wine-producing areas in the world. Growers there work with some of the best – and some of the most extreme – weather conditions in the wine-making world.

It’s cool and coastal with the long sunny days of California summers, but it is also a long, narrow valley that channels whipping winds. It also has crazy temperature swings, which can be very good – or very bad – for wine grapes.

The valley is known for the highest diurnal temperature swings in the wine-growing world. Joe, who is Foursight’s winemaker and president of the Anderson Valley Wine Association, has recorded a 62-degree swing in one day, going from 107°F (42°C) in the afternoon to 45°F (7°C) that night. This is actually a very good thing, according to Joe.

The extreme swings in temperature add to the quality of the grapes. Daytime highs provide a richness and fullness of the flavor to the fruit, while night time cool weather keeps the acidity of the grapes high – very good for premium wine grapes. But low temps can also lead to crop loss. Then there’s the wind. The winds change direction and speed on a daily basis. Warmer, drier winds zip out of the southeast to lower humidity, while cool winds bring in moisture from the northeast.

The winemakers recognize that coping with wild weather leads to improved profitability. In 2008, the weather was particularly treacherous and Foursight Wines lost nearly half their crop to an early spring frost. They recognized the need for weather stations in each vineyard to track weather conditions 24/7, including remote fields.

The Charles family now tracks conditions in all their vineyards, including the two most remote areas, on their tablets and smartphones. When temperatures drop to near 30°F (0°C), their Vantage Connect and Vantage Pro 2 weather stations send text messages so the growers can turn on overhead sprinklers to raise the temperature to avert frost damage. They can see when a temperature inversion is putting a virtual lid on their vineyard and can turn on fans to mix the air. They can track growing degree days to help determine when the fruit is ready for harvest. And the best part is that they can see these weather events from miles away or 1,000s of miles away.  

You can check out weather stations like those used by Foursight Wines on www.WeatherLink.com.