Sonoma State University weather by month
What a typical year looks like in Sonoma State University, California: average highs and lows, rain and snow, and the warmest and coldest days on record. Normals are the 1991–2020 averages at SONOMA, 19 km from Sonoma State University; records cover 1893–2026.
The year at a glance
- Precipitation a year
- 28.4 in720 mm
- Snow a year
- Rare
- Last spring freeze
- Mar 1
- First fall freeze
- Nov 24
- Heating degree days
- 2,747
- Cooling degree days
- 580
Freeze dates are medians (half of years earlier, half later). Degree days use a 65°F base; HVAC design temperatures here are 28°−2° (heating, 99%) and 101°38° (cooling, 1%).
Month by month
Sonoma State University in January
Highs average 57°14° and lows 38°4°, with 5.5 in139 mm of precipitation in a typical January.
- Record high
- 84°29° (1962)
- Record low
- 20°−7° (1960)
- Heating degree days
- 536
- Cooling degree days
- 0
Sonoma State University in February
Highs average 62°16° and lows 40°5°, with 5.4 in138 mm of precipitation in a typical February.
- Record high
- 98°37° (1894)
- Record low
- 20°−7° (1989)
- Heating degree days
- 396
- Cooling degree days
- 0
Sonoma State University in March
Highs average 65°19° and lows 42°5°, with 3.8 in98 mm of precipitation in a typical March.
- Record high
- 90°32° (1894)
- Record low
- 24°−4° (1894)
- Heating degree days
- 353
- Cooling degree days
- 1
Sonoma State University in April
Highs average 69°21° and lows 44°7°, with 1.8 in45 mm of precipitation in a typical April.
- Record high
- 100°38° (1981)
- Record low
- 20°−7° (1894)
- Heating degree days
- 256
- Cooling degree days
- 5
Sonoma State University in May
Highs average 75°24° and lows 48°9°, with 1 in26 mm of precipitation in a typical May.
- Record high
- 105°41° (1976)
- Record low
- 27°−3° (1952)
- Heating degree days
- 140
- Cooling degree days
- 33
Sonoma State University in June
Highs average 83°28° and lows 51°11°, with 0.32 in8.1 mm of precipitation in a typical June.
- Record high
- 112°44° (1961)
- Record low
- 31°−1° (1952)
- Heating degree days
- 36
- Cooling degree days
- 97
Sonoma State University in July
Highs average 86°30° and lows 54°12°, with 0 in0 mm of precipitation in a typical July.
- Record high
- 116°47° (1972)
- Record low
- 35°2° (1894)
- Heating degree days
- 6
- Cooling degree days
- 153
Sonoma State University in August
Highs average 86°30° and lows 53°12°, with 0.06 in1.5 mm of precipitation in a typical August.
- Record high
- 108°42° (1998)
- Record low
- 36°2° (1979)
- Heating degree days
- 4
- Cooling degree days
- 149
Sonoma State University in September
Highs average 85°29° and lows 51°11°, with 0.07 in1.8 mm of precipitation in a typical September.
- Record high
- 110°43° (1955)
- Record low
- 34°1° (1965)
- Heating degree days
- 18
- Cooling degree days
- 108
Sonoma State University in OctoberThis month
Highs average 78°25° and lows 47°9°, with 1.5 in39 mm of precipitation in a typical October.
- Record high
- 107°42° (1980)
- Record low
- 30°−1° (1956)
- Heating degree days
- 112
- Cooling degree days
- 33
Sonoma State University in November
Highs average 65°18° and lows 42°5°, with 3 in76 mm of precipitation in a typical November.
- Record high
- 91°33° (1985)
- Record low
- 22°−6° (1985)
- Heating degree days
- 346
- Cooling degree days
- 1
Sonoma State University in December
Highs average 57°14° and lows 38°3°, with 5.8 in148 mm of precipitation in a typical December.
- Record high
- 80°27° (1967)
- Record low
- 13°−11° (1990)
- Heating degree days
- 544
- Cooling degree days
- 0