Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Sea Ranch experiences four distinct seasons with an average annual temperature of 54°F (12°C). Winters average 49°F in January while summers reach 57°F in July / relatively mild seasonal variation. The area gets 302 sunny days per year, well above the U.S. average of 205 / making it one of the sunnier locations in the country. Annual precipitation totals 39.2 inches. Air quality is rated Good with a median AQI of 48. The city sits at an elevation of 501 feet.
Temperature
49°F Jan (10°C)57°F Jul (14°C)
Annual Average
53.6°F
1% below US avg
January Average
49°F (10°C)
July Average
57°F (14°C)
Sunny Days
302 days/yr
Geography
Elevation
501 ft (153 m)
Area
16.2 sq mi (41.9 km²)
Population Density
74/sq mi
Coordinates
38.7253°N, 123.4583°W
Timezone
America/Los_Angeles
County
Sonoma County County
Nearest Airport
San Francisco International (SFO) 96 miles away
Precipitation & Snow
Annual Rainfall39.2"
3% above US avg
Wettest Month (Jan)8.50"
Driest Month (Jul)0.12"
Air Quality
AQI Median
48.0
Rating
Good
Natural Hazard Risk
Overall Risk
Relatively High
Risk Score
99.1 / 100
Social Vulnerability
29.8 / 100
Community Resilience
66.2 / 100
Hazard Breakdown
Tornado
Very Low
Earthquake
Relatively High
Wildfire
Relatively High
Flood
Relatively High
Hail
Very Low
Strong Wind
Very Low
Heat Wave
Relatively Moderate
Winter Weather
Very Low
Lightning
Relatively Moderate
Drought
Relatively High
Cold Wave
No Rating
Landslide
Relatively High
Coastal Flood
Relatively Moderate
Tsunami
Very Low
Volcano
Relatively Low
Avalanche
Very Low
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
3,567 earthquakes (M2.5+) recorded within 150 km since 1990.
Strongest on record: M6.0.
Aug 24, 2014
The 2014 South Napa, California Earthquake
M6.0
115 km
11 km
Aug 10, 2016
20 km NNE of Upper Lake, California
M5.1
88 km
14 km
Sep 3, 2000
5 km WSW of Yountville, California
M4.9
99 km
9 km
Sep 4, 1995
13 km SW of Middletown, California
M4.8
62 km
7 km
Apr 18, 2007
15 km N of Potter Valley, California
M4.8
88 km
5 km
May 12, 2006
7 km W of Cobb, California
M4.7
57 km
4 km
Jan 2, 2025
4 km NW of Cobb, CA
M4.7
62 km
1 km
Aug 18, 1999
0 km S of Bolinas, California
M4.6
113 km
8 km
Jan 11, 2000
6 km N of Geyserville, California
M4.6
48 km
6 km
Feb 18, 2004
4 km WNW of Cobb, California
M4.6
61 km
3 km
Jan 12, 2014
8 km W of Cobb, California
M4.5
57 km
2 km
Sep 25, 2012
3 km N of Talmage, California
M4.5
55 km
11 km
Aug 3, 2006
5 km W of Glen Ellen, California
M4.5
86 km
9 km
Jun 8, 2024
7 km NW of The Geysers, CA
M4.5
56 km
4 km
Sep 19, 1992
7 km NW of Cobb, California
M4.5
60 km
3 km
Apr 24, 2007
7 km WSW of Cobb, California
M4.5
58 km
2 km
Jun 3, 2023
2km NW of The Geysers, CA
M4.5
59 km
4 km
Mar 14, 2013
5 km W of Cobb, California
M4.4
59 km
1 km
Mar 1, 2011
8 km W of Cobb, California
M4.4
56 km
2 km
Apr 12, 2023
7km WNW of Cobb, CA
M4.4
58 km
2 km
Source: USGS Earthquake Catalog (M2.5+, 1990–2025). Sorted by magnitude.
Tornado History
16 tornadoes (EF0+) recorded within 100 km since 1950.
Strongest on record: EF2.
Date
Rating
Distance
Path
Fatalities
Jun 1, 1958
EF2
65 km
15.0 mi
0
Mar 18, 2011
EF1
72 km
0.1 mi
0
Jan 27, 2005
EF1
32 km
0.5 mi
0
Dec 5, 1998
EF1
73 km
1.5 mi
0
Dec 5, 1998
EF1
83 km
1.7 mi
0
Dec 23, 1996
EF1
70 km
6.0 mi
0
Feb 22, 1996
EF1
66 km
1.0 mi
0
Dec 2, 1992
EF1
61 km
7.5 mi
0
Dec 2, 1992
EF1
66 km
1.0 mi
0
Dec 2, 1992
EF1
59 km
3.0 mi
0
Feb 27, 1983
EF1
73 km
0.8 mi
0
Nov 10, 1964
EF1
61 km
1.0 mi
0
Feb 17, 1959
EF1
29 km
0.5 mi
0
Dec 29, 2004
EF0
73 km
0.2 mi
0
Dec 11, 1983
EF0
52 km
2.0 mi
0
Feb 3, 1958
EF0
7 km
0.1 mi
0
Source: NOAA Storm Prediction Center (EF0+, 1950–2024, US only).
Tsunami History
1 tsunami recorded within 500 km.
Highest wave on record: 0.1 m (0 ft).
Year
Location
Cause
Max Wave
Deaths
Distance
1906
N. CALIFORNIA
Eruption + Earthquake
0.1 m
—
141 km
Source: NOAA/NCEI Historical Tsunami Database.
Nearby Volcanoes
1 volcano within 200 km.
Closest: Clear Lake (66 km).
Name
Type
Elevation
Last Eruption
Distance
Clear Lake
Volcanic field
1,439 m (4,721 ft)
Unknown
66 km
Source: Smithsonian Institution Global Volcanism Program (GVP).
Wildfire History
20 wildfires (100+ acres) recorded within 100 km.
Largest: RANCH (427,048 acres, 2018).
Year
Name
Acres Burned
Distance
2018
RANCH
427,048
85 km
2015
ROCKY
96,125
90 km
1996
FORK
83,209
81 km
2019
KINCADE
77,780
60 km
2015
VALLEY
77,507
74 km
2020
GLASS
68,020
81 km
2017
NUNS
56,883
93 km
2020
WALLBRIDGE
55,194
41 km
1987
MENDENHALL
54,162
98 km
2018
RIVER
48,920
53 km
1999
SIXTEEN
37,162
98 km
2017
TUBBS
36,981
70 km
2017
REDWOOD VALLEY INCIDENT
36,545
72 km
2012
MILL
29,924
98 km
2001
TROUGH
25,270
99 km
2017
POCKET
18,691
50 km
1987
FOUTS
16,892
92 km
2008
WALKER
12,441
93 km
2004
GEYSERS
12,075
62 km
1995
VISION
11,931
92 km
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
Month
Avg Temperature
Precipitation
Summary
January
49°F (10°C)
8.5 in
Wettest
February
49°F (9°C)
6.5 in
March
50°F (10°C)
6.0 in
April
52°F (11°C)
2.8 in
May
55°F (13°C)
0.8 in
June
59°F (15°C)
0.3 in
July
57°F (14°C)
0.1 in
Driest
August
62°F (17°C)
0.3 in
Warmest
September
62°F (16°C)
0.7 in
October
58°F (15°C)
2.6 in
November
52°F (11°C)
6.8 in
December
48°F (9°C)
7.2 in
Coldest
Sea Ranch has a seasonal temperature swing of 14°F / from 48°F in December to 62°F in August. Total annual precipitation is 42.6 inches, with January being the wettest month (8.5") and July the driest (0.1").