Although no official temperature records exist for Guerneville, the nearby town of Graton has average January temperatures ranging from , and July temperatures from . There are an average of 28.7 days annually with highs of or higher and 44.7 days annually with lows of or lower. The record high temperature was on July 14, 1972, and the record low temperature was on December 22, 1990. Other nearby cooperative National Weather Service stations are in Occidental, Cazadero, and Fort Ross.
Although no official temperature records exist for Guerneville, the nearby town of Graton has average, January temperatures ranging from , and July temperatures from . There are an average of 28.7 days annually with highs of or higher and 44.7 days annually with lows of or lower. The record high temperature was on July 14 1972 and the record low tempera,ture was on December 22, 1990. Other nearby cooperative National Weather Service stations are in Occidental, Cazadero, and Fort Ross.