Sign In Register

Weather & Climate in Westley, CA

Temperature, precipitation, air quality, natural hazards, and monthly weather data.

Westley enjoys a temperate climate with an average annual temperature of 61°F (16°C). Winters average 47°F in January while summers reach 75°F in July. The area gets 330 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 12.7 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 92 feet.

Temperature

47°F Jan (8°C) 75°F Jul (24°C)
Annual Average61.0°F
13% above US avg
January Average47°F (8°C)
July Average75°F (24°C)
Sunny Days330 days/yr

Geography

Elevation92 ft (28 m)
Area0.4 sq mi (0.9 km²)
Population Density2,121/sq mi
Coordinates37.5469°N, 121.2009°W
TimezoneAmerica/Los_Angeles
CountyStanislaus County County
Nearest AirportNorman Y Mineta San Jose International (SJC)
42 miles away

Precipitation & Snow

Annual Rainfall 12.7"
67% below US avg
Wettest Month (Jan) 2.24"
Driest Month (Jul) 0.04"

Air Quality

AQI Median48.0
RatingGood

Natural Hazard Risk

Overall RiskRelatively High
Risk Score96.9 / 100
Social Vulnerability32.0 / 100
Community Resilience33.9 / 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 Moderate
Winter Weather Relatively Low
Lightning Relatively High
Drought Very High
Cold Wave No Rating
Landslide Relatively Low
Volcano Very Low
Avalanche Very Low
Source: FEMA National Risk Index v1.20 (Dec 2025)

Earthquake History

4,253 earthquakes (M2.5+) recorded within 150 km since 1990. Strongest on record: M6.0.

Aug 24, 2014 The 2014 South Napa, California Earthquake M6.0 123 km 11 km
Apr 18, 1990 5 km NNW of Aromas, California M5.4 79 km 5 km
Oct 21, 2012 24 km NE of San Lucas, California M5.3 141 km 9 km
Apr 18, 1990 4 km E of Interlaken, California M5.1 78 km 7 km
Aug 12, 1998 10 km SW of Ridgemark, California M5.1 91 km 9 km
Jan 16, 1993 9 km E of Gilroy, California M4.9 63 km 7 km
Apr 23, 1995 22 km NNE of Soledad, California M4.9 105 km 7 km
Sep 3, 2000 5 km WSW of Yountville, California M4.9 141 km 9 km
May 14, 2002 5 km SSW of Gilroy, California M4.9 74 km 7 km
Apr 19, 1996 2 km E of Aromas, California M4.9 82 km 5 km
Apr 18, 1990 4 km NNW of Aromas, California M4.9 80 km 6 km
Apr 18, 1990 4 km N of Aromas, California M4.7 79 km 4 km
May 21, 1996 8 km ESE of East Foothills, California M4.7 51 km 8 km
Aug 11, 1993 14 km ESE of Alum Rock, California M4.7 50 km 9 km
Aug 27, 2011 21 km NE of Soledad, California M4.6 107 km 8 km
Mar 24, 1991 1 km NNE of Interlaken, California M4.6 80 km 15 km
Aug 18, 1999 0 km S of Bolinas, California M4.6 137 km 8 km
Sep 19, 2023 15 km SW of Westley, CA M4.5 15 km 4 km
Jan 12, 2011 9 km SSE of San Juan Bautista, California M4.5 90 km 8 km
Jan 20, 2015 27 km ENE of Greenfield, California M4.4 126 km 9 km
Source: USGS Earthquake Catalog (M2.5+, 1990–2025). Sorted by magnitude.

Tornado History

85 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF2. Total: 9 injuries.

Date Rating Distance Path Fatalities
May 5, 1998 EF2 76 km 0.6 mi 0
Mar 11, 1985 EF2 80 km 0.5 mi 0
Apr 27, 1953 EF2 21 km 0.1 mi 0
Jan 11, 1951 EF2 84 km 5.7 mi 0
Dec 14, 2024 EF1 92 km 0.3 mi 0
Mar 11, 2023 EF1 73 km 0.8 mi 0
Jan 10, 2023 EF1 71 km 0.4 mi 0
Nov 15, 2015 EF1 34 km 3.0 mi 0
Jan 23, 2010 EF1 64 km 1.6 mi 0
Apr 14, 2006 EF1 21 km 0.5 mi 0
Dec 16, 2002 EF1 65 km 1.3 mi 0
Dec 20, 2001 EF1 82 km 0.5 mi 0
May 5, 1998 EF1 83 km 0.3 mi 0
Feb 14, 1998 EF1 99 km 3.0 mi 0
Dec 12, 1996 EF1 40 km 0.6 mi 0
Nov 22, 1996 EF1 71 km 0.2 mi 0
Jan 14, 1995 EF1 95 km 1.0 mi 0
Apr 19, 1988 EF1 69 km 0.2 mi 0
Jan 14, 1980 EF1 60 km 0.3 mi 0
Mar 4, 1978 EF1 34 km 1.0 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 81 km
1989 N. CALIFORNIA Earthquake 1.0 m 62 83 km
1856 N. CALIFORNIA Eruption + Earthquake 0.6 m — 97 km
1906 N. CALIFORNIA Eruption + Earthquake 0.1 m — 116 km
1865 N. CALIFORNIA Eruption + Earthquake — — 73 km
Source: NOAA/NCEI Historical Tsunami Database.

Nearby Volcanoes

3 volcanoes within 200 km. Closest: Mammoth Mountain (191 km).

Name Type Elevation Last Eruption Distance
Mammoth Mountain Lava dome(s) 3,369 m (11,053 ft) 1260 191 km
Mono-Inyo Craters Lava dome(s) 2,796 m (9,173 ft) 1380 193 km
Mono Lake Volcanic Field Pyroclastic cone(s) 2,121 m (6,959 ft) 1790 197 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 27 km
2017 DETWILER 83,297 95 km
2015 BUTTE 72,894 96 km
2007 LICK 47,424 41 km
2006 CANYON 36,851 24 km
1992 GULCH 18,019 95 km
2003 ANNIE 17,383 36 km
1996 MERCY 16,993 83 km
2024 CORRAL 16,138 25 km
2018 WAVERLY 12,238 59 km
1984 BONANZA 12,105 92 km
2009 CORRAL 12,006 26 km
1985 LEXINGTON 11,550 77 km
2001 CREEK 9,793 89 km
1992 MOCCASIN 9,565 86 km
2000 HUNTER 7,734 91 km
2003 BIRD 7,727 12 km
1985 PONOCHE 2 7,508 99 km
1984 SITE 300 3 6,911 27 km
2005 TESLA 6,638 35 km
Source: NIFC/IRWIN Wildfire Records (100+ acres).

Monthly Weather

Month Avg Temperature Precipitation Summary
January 47°F (8°C) 2.2 in Wettest
February 51°F (10°C) 1.8 in
March 55°F (13°C) 1.8 in
April 59°F (15°C) 0.9 in
May 65°F (19°C) 0.2 in
June 72°F (22°C) 0.1 in
July 75°F (24°C) 0.0 in Driest
August 76°F (24°C) 0.1 in Warmest
September 72°F (22°C) 0.3 in
October 66°F (19°C) 0.7 in
November 55°F (13°C) 1.9 in
December 46°F (8°C) 1.7 in Coldest

Westley has a seasonal temperature swing of 29°F / from 46°F in December to 76°F in August. Total annual precipitation is 11.7 inches, with January being the wettest month (2.2") and July the driest (0.0").

View full profile of Westley, CA →