Understanding Napa Valley’s Unusual Winter Weather

At Napa Valley Grapegrowers, understanding weather trends is key to supporting sustainable vineyard practices. Recently, we spoke with Erik Moldstad from Precision Forecasting to discuss the current dry and sunny conditions affecting our region.

A Dry Winter Explained
​This season, Napa Valley has experienced drier-than-average weather following a wet early winter. Erik attributes this to a La Niña pattern combined with warmer-than-usual ocean temperatures across the Pacific.

“These warmer ocean temperatures create high-pressure systems along the coast, blocking rain and resulting in dry, sunny weather,” Erik explained. Napa often falls between the extremes of wetter weather in the Pacific Northwest and drier conditions in Southern California during La Niña years. Unfortunately, the forecast for the second half of winter points to less frequent and lighter rain than usual.

Hopes for Rain?
When asked about the likelihood of an atmospheric river breaking through, Erik shared that while some rain is possible, high-pressure systems are expected to dominate. Still, Napa’s early-season rains have filled reservoirs and replenished soil moisture, putting the region in a better position despite the dry outlook.

Looking Ahead
While the forecast suggests continued dryness, Napa Valley is well-prepared thanks to early winter rains. Erik encourages growers to enjoy the mild weather while staying informed. His forecasts, available through Precision Forecasting, provide valuable insights to help vineyard managers adapt to changing conditions.