Weather in Sonoma County

Calculated from weather data of Gnoss Field (KDVO) between 2020 and 2024.

Maximum temperatures (°F)

Month	Average	2024	2023	2022	2021	2020
January	59.0	60.0	58.0	60.0	60.0	59.0
February	62.0	61.0	59.0	66.0	65.0	68.0
March	64.0	63.0	58.0	69.0	65.0	64.0
April	70.0		69.0	70.0	72.0	70.0
May	74.0		71.0	77.0	78.0	77.0
June	82.0		75.0	84.0	82.0	85.0
July	86.0		87.0	84.0	87.0	86.0
August	87.0		89.0	88.0	87.0	90.0
September	85.0		80.0	88.0	87.0	89.0
October	79.0		80.0	78.0	74.0	85.0
November	66.0		68.0	64.0	65.0	67.0
December	58.0		61.0	54.0	55.0	60.0
Average	71.0	61.0	71.0	74.0	73.0	75.0

Average highest temperature per day

The maximum temperature is typically observed some hours after noon.

Minimum temperatures (°F)

Month	Average	2024	2023	2022	2021	2020
January	42.0	46	44	41	40	42
February	41.0	44	39	39	41	39
March	44.0	46	43	44	39	42
April	46.0		46	46	41	46
May	49.0		50	49	48	49
June	52.0		52	53	52	52
July	51.0		51	53	52	51
August	54.0		54	54	53	55
September	52.0		51	51	52	54
October	47.0		47	47	48	49
November	41.0		43	36	46	39
December	40.0		44	37	42	37
Average	47.0	45.0	47.0	46.0	46.0	46.0

Average lowest temperature per day

The minimum temperature is typically observed just before sunrise.

Cold and hot days

Number of days	2024	2023	2022	2021	2020
86 °F or warmer	0	54	61	58	91
77 °F or warmer	0	113	135	139	158
68 °F or warmer	7	181	218	208	218
32 °F or colder	0	7	11	3	9

Precipitation (%)

Month	Average	2024	2023	2022	2021	2020
January	8.0	15	13	1	3	2
February	6.1	22	6	0	0	0
March	4.3	11	9	1	2	2
April	1.5		0	1	0	2
May	0.6		0	0	0	1
June	0.0		0	0	0	0
July	0.2		0	0	0	0
August	0.2		0	0	0	1
September	0.2		0	1	0	0
October	0.6		0	0	4	0
November	1.6		3	1	1	1
December	5.6		16	5	4	1
Average	3.6	15.7	3.6	0.7	1.0	0.8

Precipitation during daylight period

Percentage of observations with observed rain, drizzle, snow or hail. Only observations between sunrise and sunset are taken into account.

Wind speed (miles per hour)

Month	Average	2024	2023	2022	2021	2020
January	5.7	6	7	4	6	6
February	6.9	6	7	5	7	6
March	7.0	8	9	6	8	6
April	7.2		8	9	7	7
May	7.9		7	10	9	7
June	7.1		7	8	8	8
July	6.1		6	7	6	6
August	5.8		6	6	6	6
September	6.3		7	6	6	6
October	5.4		5	5	7	5
November	4.8		5	5	4	6
December	5.5		5	5	7	5
Average	6.4	6.9	6.4	6.4	6.7	6.1

Average wind speed

Excluding wind gusts. Only observations between sunrise and sunset are taken into account.

Prevailing wind direction

Month	2024	2023	2022	2021	2020
January	S	S	SE	NE	W
February	S	W	NW	NW	N
March	W	SW	NW	W	W
April		W	W	SW	W
May		SW	W	W	SW
June		SW	W	W	W
July		S	SW	NE	NW
August		SW	W	N	W
September		SW	SW	NW	NW
October		W	NW	SW	SE
November		S	SW	SE	W
December		S	S	SW	SE

Prevailing wind direction

Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.

Sonoma County weather Q&A

What is the warmest month in Sonoma County?

The warmest month is August with an average temperature of 87 °F over the past years.

What is the coldest month in Sonoma County?

The coldest month is December with an average daytime temperature of 58 °F in the past few years.

Which month is the wettest in Sonoma County?

Chance of precipitation is the highest in January with a probability of around 8.0 %.

Which month is the driest in Sonoma County?

The least rainfall and snow can be expected in June. The probability is about 0.1 %.