Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Blackhawk enjoys a temperate climate with an average annual temperature of 58°F (15°C). Winters average 48°F in January while summers reach 72°F in July. The area gets 323 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 26.1 inches (drier than the 38-inch national average). Air quality is rated Good with a median AQI of 48. The city sits at an elevation of 863 feet.
Temperature
48°F Jan (9°C)72°F Jul (22°C)
Annual Average
58.4°F
8% above US avg
January Average
48°F (9°C)
July Average
72°F (22°C)
Sunny Days
323 days/yr
Geography
Elevation
863 ft (263 m)
Area
5.8 sq mi (15.0 km²)
Population Density
1,800/sq mi
Coordinates
37.8096°N, 121.9132°W
Timezone
America/Los_Angeles
County
Contra Costa County County
Nearest Airport
Metro Oakland International (OAK) 18 miles away
Precipitation & Snow
Annual Rainfall26.1"
31% below US avg
Snowfall0.7"
Wettest Month (Jan)3.78"
Driest Month (Jul)0.04"
Air Quality
AQI Median
48.0
Rating
Good
Natural Hazard Risk
Overall Risk
Very High
Risk Score
99.5 / 100
Social Vulnerability
21.5 / 100
Community Resilience
67.8 / 100
Hazard Breakdown
Tornado
Relatively Low
Earthquake
Relatively High
Wildfire
Relatively Moderate
Flood
Very High
Hail
Very Low
Strong Wind
Relatively Low
Heat Wave
Relatively High
Winter Weather
Very Low
Lightning
Relatively High
Drought
Relatively High
Cold Wave
No Rating
Landslide
Relatively High
Coastal Flood
Relatively Moderate
Tsunami
Relatively Low
Volcano
Very Low
Avalanche
Very Low
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
5,856 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
57 km
11 km
Apr 18, 1990
5 km NNW of Aromas, California
M5.4
100 km
5 km
Aug 12, 1998
10 km SW of Ridgemark, California
M5.1
124 km
9 km
Apr 18, 1990
4 km E of Interlaken, California
M5.1
97 km
7 km
Jan 16, 1993
9 km E of Gilroy, California
M4.9
97 km
7 km
Sep 3, 2000
5 km WSW of Yountville, California
M4.9
77 km
9 km
May 14, 2002
5 km SSW of Gilroy, California
M4.9
98 km
7 km
Apr 23, 1995
22 km NNE of Soledad, California
M4.9
148 km
7 km
Apr 19, 1996
2 km E of Aromas, California
M4.9
106 km
5 km
Apr 18, 1990
4 km NNW of Aromas, California
M4.9
100 km
6 km
Sep 4, 1995
13 km SW of Middletown, California
M4.8
121 km
7 km
May 12, 2006
7 km W of Cobb, California
M4.7
137 km
4 km
May 21, 1996
8 km ESE of East Foothills, California
M4.7
53 km
8 km
Apr 18, 1990
4 km N of Aromas, California
M4.7
101 km
4 km
Aug 11, 1993
14 km ESE of Alum Rock, California
M4.7
59 km
9 km
Jan 2, 2025
4 km NW of Cobb, CA
M4.7
137 km
1 km
Aug 18, 1999
0 km S of Bolinas, California
M4.6
69 km
8 km
Mar 24, 1991
1 km NNE of Interlaken, California
M4.6
95 km
15 km
Jan 11, 2000
6 km N of Geyserville, California
M4.6
138 km
6 km
Feb 18, 2004
4 km WNW of Cobb, California
M4.6
136 km
3 km
Source: USGS Earthquake Catalog (M2.5+, 1990-2025). Sorted by magnitude.
Tornado History
75 tornadoes (EF0+) recorded within 100 km since 1950.
Strongest on record: EF2. Total: 9 injuries.
Date
Rating
Distance
Path
Fatalities
May 5, 1998
EF2
50 km
0.6 mi
0
Apr 27, 1953
EF2
82 km
0.1 mi
0
Jan 11, 1951
EF2
52 km
5.7 mi
0
Dec 14, 2024
EF1
85 km
0.3 mi
0
Mar 18, 2011
EF1
100 km
0.1 mi
0
Jan 23, 2010
EF1
17 km
1.6 mi
0
Apr 14, 2006
EF1
82 km
0.5 mi
0
Mar 20, 2005
EF1
48 km
3.0 mi
0
Dec 20, 2001
EF1
94 km
0.5 mi
0
Dec 5, 1998
EF1
99 km
1.5 mi
0
May 5, 1998
EF1
51 km
0.3 mi
0
Dec 12, 1996
EF1
94 km
0.6 mi
0
Apr 19, 1988
EF1
78 km
0.2 mi
0
Feb 27, 1983
EF1
99 km
0.8 mi
0
Jan 14, 1980
EF1
37 km
0.3 mi
0
Mar 4, 1978
EF1
97 km
2.5 mi
0
Mar 1, 1978
EF1
88 km
1.5 mi
0
May 31, 1967
EF1
57 km
0.1 mi
0
Apr 1, 1965
EF1
93 km
0.1 mi
0
Apr 1, 1958
EF1
44 km
0.2 mi
0
Source: NOAA Storm Prediction Center (EF0+, 1950-2024, US only).
Tsunami History
5 tsunamis recorded within 500 km.
Highest wave on record: 4.5 m (15 ft).
Year
Location
Cause
Max Wave
Deaths
Distance
1868
N. CALIFORNIA
Eruption + Earthquake
4.5 m
30
20 km
1989
N. CALIFORNIA
Earthquake
1.0 m
62
86 km
1856
N. CALIFORNIA
Eruption + Earthquake
0.6 m
-
48 km
1906
N. CALIFORNIA
Eruption + Earthquake
0.1 m
-
53 km
1865
N. CALIFORNIA
Eruption + Earthquake
-
-
68 km
Source: NOAA/NCEI Historical Tsunami Database.
Nearby Volcanoes
1 volcano within 200 km.
Closest: Clear Lake (149 km).
Name
Type
Elevation
Last Eruption
Distance
Clear Lake
Volcanic field
1,439 m (4,721 ft)
Unknown
149 km
Source: Smithsonian Institution Global Volcanism Program (GVP).
Wildfire History
20 wildfires (100+ acres) recorded within 100 km.
Largest: SCU LIGHTNING COMPLEX (405,787 acres, 2020).
Year
Name
Acres Burned
Distance
2020
SCU LIGHTNING COMPLEX
405,787
51 km
2020
HENNESSEY
314,241
96 km
2018
COUNTY
92,450
99 km
2020
CZU AUG LIGHTNING
85,894
79 km
2020
GLASS
68,020
100 km
2017
NUNS
56,883
79 km
2017
ATLAS
51,664
68 km
2007
LICK
47,424
78 km
2006
CANYON
36,851
71 km
1988
MILLER
35,750
71 km
2003
ANNIE
17,383
87 km
2024
CORRAL
16,138
44 km
2018
WAVERLY
12,238
96 km
2009
CORRAL
12,006
45 km
1995
VISION
11,931
87 km
1985
LEXINGTON
11,550
74 km
2015
WRAGG
8,455
76 km
2009
LOCKHEED
8,287
85 km
2003
BIRD
7,727
59 km
2014
MONTICELLO
6,984
82 km
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
Month
Avg Temperature
Precipitation
Summary
January
48°F (9°C)
3.8 in
Wettest
February
51°F (10°C)
3.2 in
March
53°F (12°C)
3.0 in
April
57°F (14°C)
1.2 in
May
61°F (16°C)
0.4 in
June
66°F (19°C)
0.1 in
July
72°F (22°C)
0.0 in
Warmest, Driest
August
70°F (21°C)
0.1 in
September
69°F (20°C)
0.3 in
October
63°F (17°C)
1.1 in
November
54°F (12°C)
2.6 in
December
47°F (9°C)
2.9 in
Coldest
Blackhawk has a seasonal temperature swing of 25°F / from 47°F in December to 72°F in July. Total annual precipitation is 18.7 inches, with January being the wettest month (3.8") and July the driest (0.0").