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Discovery Bay, CA
Full City Profile · California · San Joaquin County County
3.2
/5.0
B
Good
15,243
Population
2,727/sq mi density
$154,792
Median Income
$64,234 per capita
$789,400
Home Value
$785,548 Zillow
$2,897
Median Rent
35.6% income on rent
64°F
Avg Temperature
330 sunny days/yr
183
Violent Crime/100K
2,239 property/100K
B
Overall
3.2 / 5.0
Good overall score based on economy, affordability, safety and education
A+
Economy
4.5 / 5.0
$154,792 median income, 5.1% unemployment
B+
Affordability
3.8 / 5.0
$789,400 home value, $2,897/mo rent
F
Safety
1.0 / 5.0
183 violent crimes/100K
B+
Education
3.6 / 5.0
33.1% bachelor's degree or higher
Discovery Bay enjoys a temperate climate with an average annual temperature of 64°F (18°C). Winters average 48°F in January while summers reach 78°F in July. The area gets 330 sunny days per year. Annual precipitation totals 12.4 inches. The area receives 0.0 inches of snow annually. Air quality is rated Good with a median AQI of 48.
Temperature
48°F Jan (9°C)
78°F Jul (25°C)
| Annual Average | 63.5°F |
| 18% above US avg | |
| January Average | 48°F (9°C) |
| July Average | 78°F (25°C) |
| Sunny Days | 330 days/yr |
Geography
| Elevation | 1 ft (0 m) |
| Area | 5.6 sq mi (14.5 km²) |
| Population Density | 2,727/sq mi |
| Coordinates | 37.9081°N, 121.5972°W |
| Timezone | America/Los_Angeles |
| County | San Joaquin County County |
| Nearest Airport | Metro Oakland International (OAK) 36 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 48.0 |
| Rating | Good |
Air Pollutants (EPA 2023)
| Ozone (O₃) | 0.0391 ppm |
| NO₂ (Nitrogen Dioxide) | 10.1 ppb |
| CO (Carbon Monoxide) | 0.27 ppm |
| PM2.5 (Fine Particles) | 9.5 μg/m³ |
Natural Hazard Risk
| Overall Risk | Relatively High |
| Risk Score | 98.6 / 100 |
| Social Vulnerability | 39.7 / 100 |
| Community Resilience | 47.0 / 100 |
Hazard Breakdown
| Tornado | Relatively Low |
| Earthquake | Relatively High |
| Wildfire | Relatively Moderate |
| Flood | Relatively High |
| Hail | Relatively Low |
| Strong Wind | Relatively Low |
| Heat Wave | Relatively High |
| Winter Weather | Relatively Low |
| Lightning | Relatively High |
| Drought | Very High |
| Cold Wave | No Rating |
| Landslide | Very Low |
| Volcano | Very Low |
| Avalanche | Very Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
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 | 50 km |
| 1989 | N. CALIFORNIA | Earthquake | 1.0 m | 62 | 100 km |
| 1856 | N. CALIFORNIA | Eruption + Earthquake | 0.6 m | — | 77 km |
| 1906 | N. CALIFORNIA | Eruption + Earthquake | 0.1 m | — | 83 km |
| 1865 | N. CALIFORNIA | Eruption + Earthquake | — | — | 83 km |
Source: NOAA/NCEI Historical Tsunami Database. Sorted by wave height.
Nearby Volcanoes
1 volcano within 200 km. Closest: Clear Lake (156 km).
| Name | Type | Elevation | Last Eruption | Distance |
| Clear Lake | Volcanic field | 1,439 m (4,721 ft) | Unknown | 156 km |
Source: Smithsonian Institution Global Volcanism Program (GVP). Sorted by distance.
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 48°F (9°C) | 2.5 in | Wettest |
| February | 51°F (11°C) | 2.1 in | |
| March | 55°F (13°C) | 1.7 in | |
| April | 59°F (15°C) | 0.8 in | |
| May | 65°F (18°C) | 0.3 in | |
| June | 70°F (21°C) | 0.1 in | |
| July | 78°F (25°C) | 0.0 in | Warmest, Driest |
| August | 73°F (23°C) | 0.1 in | |
| September | 70°F (21°C) | 0.2 in | |
| October | 64°F (18°C) | 0.8 in | |
| November | 54°F (12°C) | 1.8 in | |
| December | 46°F (8°C) | 1.8 in | Coldest |
Discovery Bay has a seasonal temperature swing of 32°F / from 46°F in December to 78°F in July. Total annual precipitation is 12.3 inches, with January being the wettest month (2.5") and July the driest (0.0").