Angwin is a census-designated place (CDP) in Napa County, United States. California. It is part of the northern San Francisco Bay Area. The population was 3,051 at the 2010 census. Its area code is 707. Its two zip codes are 94508 and 94576. It is in the Pacific time zone.
The town was named in 1874 for Edwin Angwin who ran a resort on the land the town now occupies.. Edwin Angwin (1841–1919) was a native of St. Agnes, Cornwall. Angwin is a Cornish surname meaning "the white" (an = the; gwynn = white) and is comparable to the English surname "White."
Angwin is home to a large number of Seventh-day Adventists. In 1909, Pacific Union College, an Adventist liberal arts college, moved from Healdsburg to Angwin..Although many of the residents refrain from drinking alcohol because of religious beliefs, the area is becoming a popular area for winemakers to plant vineyards and build wineries.
According to the United States Census Bureau, the CDP has a total area of 4.9 square miles (13 km2), 99.14% of it land and 0.86% of it water.
Angwin's Pacific Union College has maintained a National Weather Service cooperative weather station since 1940. Average January temperatures are a maximum of 52.2 °F (11.2 °C) and a minimum of 37.9 °F (3.3 °C). There are an average of 35.3 days with highs of 90.0 °F (32.2 °C) or higher and 25.1 days with lows of 32.0 °F (0.0 °C) or lower. The record high temperature was 110 °F (43 °C) on July 15, 1972. The record low temperature was 14 °F (−10 °C) on December 9, 1972.
Average annual precipitation is 40.60 inches (103.1 cm). The wettest year was 1983 with 88.89 inches (225.8 cm) and the driest year was 1990 with 19.00 inches (48.3 cm). The most precipitation in one month was 30.44 inches (77.3 cm) in December 1955. The most precipitation in 24 hours was 7.40 inches (18.8 cm) on February 17, 1986.
Average annual snowfall is 2.0 inches (5.1 cm). The most snow in one year was 23.3 inches (59 cm) in 1952, including 12.8 inches (33 cm) in January.