Growing Conditions

© Stephen Rothfeld

Growing Conditions Report

The Growing Conditions Report, produced in cooperation with Pacific Geodata, Picovale Weather Service, and Premiere Viticultural Services, contains maps, tables, and graphs depicting regional Napa climate data and will provide a countywide overview of general growing conditions.


The report employs three simple and widely understood climate measurements known to influence grapevine development, ripening, and crop loads: growing degree days (GDD), total frost hours, and rainfall.  Additionally, the report provides data for previous growing seasons (starting in 2009), allowing grapegrowers to compare conditions across vintages.  Over time, a multi-year collection of reports will add to our understanding of regional climate conditions and help to identify climate trends.