Sonoma Country has mild winters and warm dry summers.Each of the valleys is a distinct micro-climate depending on how near to the sea, the sheltering hills and mountains, and the elevations of the vineyards. Daytime summer temperatures can reach over 100 degrees, but by evening the temperatures are mostly cool. In the wintertime temperatures may drop into the 20’s creating frost problems for growers. Coastal areas in the summer are often fogged during the day and frequently also at night. Annual rainfall ranges from 25 inches in the valleys to over 70 inches in the mountains. Rain begins to fall in November and continues through March.