Weather & Climate in Folsom, CA
Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Folsom enjoys a temperate climate with an average annual temperature of 63°F (17°C). Winters average 49°F in January while summers reach 78°F in July. Annual precipitation totals 20.9 inches (drier than the 38-inch national average). Air quality is rated Moderate with a median AQI of 51. 50% of days have good air quality. The city sits at an elevation of 325 feet.
Temperature
49°F Jan (9°C)
78°F Jul (26°C)
| Annual Average | 63.4°F |
| 17% above US avg | |
| January Average | 49°F (9°C) |
| July Average | 78°F (26°C) |
Geography
| Elevation | 325 ft (99 m) |
| Area | 24.3 sq mi (62.9 km²) |
| Population Density | 2,946/sq mi |
| Coordinates | 38.6666°N, 121.1416°W |
| Timezone | America/Los_Angeles |
| County | Sacramento County County |
| Nearest Airport | Sacramento International (SMF) 24 miles away |
Precipitation & Snow
Air Quality
| AQI Median | 51.0 |
| Rating | Moderate |
| Good Days % | 49.7% |
| Unhealthy Days | 15 |
Natural Hazard Risk
| Overall Risk | Relatively High |
| Risk Score | 98.1 / 100 |
| Social Vulnerability | 37.4 / 100 |
| Community Resilience | 57.0 / 100 |
Hazard Breakdown
| Tornado | Relatively Moderate |
| Earthquake | Relatively High |
| Wildfire | Relatively Moderate |
| Flood | Relatively High |
| Hail | Relatively 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 Low |
| Coastal Flood | No Rating |
| Volcano | Very Low |
Source: FEMA National Risk Index v1.20 (Dec 2025)
Earthquake History
5,263 earthquakes (M2.5+) recorded within 150 km since 1990. Strongest on record: M6.1.
| Sep 12, 1994 | 4 km S of Carter Springs, Nevada | M6.1 | 130 km | 14 km |
| Aug 24, 2014 | The 2014 South Napa, California Earthquake | M6.0 | 114 km | 11 km |
| Jul 8, 2021 | Antelope Valley, CA | M6.0 | 144 km | 7 km |
| Aug 10, 2001 | 3 km N of Blairsden, California | M5.2 | 135 km | 5 km |
| Apr 26, 2008 | 1 km NW of Mogul, Nevada | M5.1 | 141 km | 3 km |
| Sep 12, 1994 | 8 km ESE of Mesa Vista, California | M5.1 | 125 km | -1 km |
| Jul 8, 2021 | 32km SE of Markleeville, CA | M5.0 | 144 km | 7 km |
| Sep 3, 2000 | 5 km WSW of Yountville, California | M4.9 | 115 km | 9 km |
| Dec 22, 1995 | California-Nevada border region | M4.9 | 131 km | 4 km |
| Sep 4, 1995 | 13 km SW of Middletown, California | M4.8 | 139 km | 7 km |
| Apr 26, 2008 | 0 km N of Mogul, Nevada | M4.8 | 141 km | 3 km |
| Oct 30, 1998 | 4 km N of Tahoe Vista, California | M4.8 | 117 km | 1 km |
| Dec 28, 1995 | 9 km WNW of Topaz Lake, Nevada | M4.8 | 129 km | -1 km |
| Jun 26, 2005 | 8 km NNW of Tahoe Vista, California | M4.8 | 115 km | -2 km |
| May 12, 2006 | 7 km W of Cobb, California | M4.7 | 146 km | 4 km |
| Dec 23, 1995 | 8 km WNW of Topaz Lake, Nevada | M4.7 | 131 km | -1 km |
| Jan 2, 2025 | 4 km NW of Cobb, CA | M4.7 | 141 km | 1 km |
| May 7, 2021 | 19km NW of Truckee, CA | M4.7 | 114 km | 10 km |
| Jul 8, 2021 | 29km ENE of Dardanelle, CA | M4.6 | 140 km | 2 km |
| Dec 12, 1996 | 4 km SSW of Topaz Lake, Nevada | M4.6 | 137 km | -2 km |
Source: USGS Earthquake Catalog (M2.5+, 1990-2025). Sorted by magnitude.
Tornado History
69 tornadoes (EF0+) recorded within 100 km since 1950. Strongest on record: EF2. Total: 1 injury.
| Date | Rating | Distance | Path | Fatalities |
| Feb 7, 1978 | EF2 | 27 km | 1.9 mi | 0 |
| Mar 11, 2023 | EF1 | 98 km | 0.8 mi | 0 |
| Jan 10, 2023 | EF1 | 73 km | 0.4 mi | 0 |
| Dec 24, 2015 | EF1 | 5 km | 6.2 mi | 0 |
| Oct 22, 2012 | EF1 | 42 km | 4.0 mi | 0 |
| Oct 22, 2012 | EF1 | 57 km | 0.3 mi | 0 |
| Oct 22, 2012 | EF1 | 61 km | 2.0 mi | 0 |
| Jan 23, 2010 | EF1 | 100 km | 1.6 mi | 0 |
| Jan 8, 2005 | EF1 | 95 km | 0.1 mi | 0 |
| Jan 7, 1993 | EF1 | 98 km | 0.1 mi | 0 |
| Dec 17, 1992 | EF1 | 76 km | 5.0 mi | 0 |
| Apr 19, 1988 | EF1 | 55 km | 0.2 mi | 0 |
| Apr 19, 1988 | EF1 | 3 km | 1.0 mi | 0 |
| Mar 22, 1983 | EF1 | 19 km | 2.0 mi | 0 |
| Jun 28, 1970 | EF1 | 95 km | 2.3 mi | 0 |
| May 31, 1967 | EF1 | 79 km | 0.1 mi | 0 |
| Jan 14, 2023 | EF0 | 39 km | 0.3 mi | 0 |
| Nov 8, 2022 | EF0 | 41 km | 0.8 mi | 0 |
| Nov 18, 2020 | EF0 | 13 km | 4.4 mi | 0 |
| May 18, 2020 | EF0 | 31 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: 4.5 m (15 ft).
| Year | Location | Cause | Max Wave | Deaths | Distance |
| 1868 | N. CALIFORNIA | Eruption + Earthquake | 4.5 m | 30 | 136 km |
Source: NOAA/NCEI Historical Tsunami Database.
Nearby Volcanoes
2 volcanoes within 200 km. Closest: Clear Lake (145 km).
| Name | Type | Elevation | Last Eruption | Distance |
| Clear Lake | Volcanic field | 1,439 m (4,721 ft) | Unknown | 145 km |
| Mono Lake Volcanic Field | Pyroclastic cone(s) | 2,121 m (6,959 ft) | 1790 | 199 km |
Source: Smithsonian Institution Global Volcanism Program (GVP).
Wildfire History
20 wildfires (100+ acres) recorded within 100 km. Largest: HENNESSEY (314,241 acres, 2020).
| Year | Name | Acres Burned | Distance |
| 2020 | HENNESSEY | 314,241 | 99 km |
| 2021 | CALDOR | 226,583 | 74 km |
| 2014 | KING | 99,070 | 60 km |
| 2018 | COUNTY | 92,450 | 88 km |
| 2022 | MOSQUITO | 77,858 | 57 km |
| 2015 | BUTTE | 72,894 | 65 km |
| 2004 | RUMSEY | 39,335 | 99 km |
| 1988 | 49R | 36,673 | 65 km |
| 1988 | MILLER | 35,750 | 87 km |
| 2013 | AMERICAN | 27,938 | 71 km |
| 1992 | CLEVELAND | 21,835 | 64 km |
| 2008 | AMERICAN RIVER COMPLEX (GOVERNMENT) | 20,709 | 77 km |
| 1992 | GULCH | 18,019 | 79 km |
| 2004 | POWER | 17,266 | 77 km |
| 2001 | STAR | 16,846 | 74 km |
| 2017 | CASCADE | 16,155 | 80 km |
| 2001 | DARBY | 14,734 | 90 km |
| 2006 | ZAM ASSIST | 14,404 | 67 km |
| 2018 | WAVERLY | 12,238 | 79 km |
| 1996 | SCOTT | 8,828 | 14 km |
Source: NIFC/IRWIN Wildfire Records (100+ acres).
Monthly Weather
| Month | Avg Temperature | Precipitation | Summary |
|---|---|---|---|
| January | 49°F (9°C) | 4.3 in | Wettest |
| February | 53°F (12°C) | 4.2 in | |
| March | 57°F (14°C) | 3.3 in | |
| April | 61°F (16°C) | 1.8 in | |
| May | 68°F (20°C) | 1.0 in | |
| June | 74°F (23°C) | 0.3 in | |
| July | 78°F (26°C) | 0.0 in | Warmest, Driest |
| August | 77°F (25°C) | 0.0 in | |
| September | 74°F (23°C) | 0.1 in | |
| October | 66°F (19°C) | 0.9 in | |
| November | 55°F (13°C) | 1.6 in | |
| December | 49°F (9°C) | 3.4 in | Coldest |
Folsom has a seasonal temperature swing of 29°F / from 49°F in December to 78°F in July. Total annual precipitation is 20.9 inches, with January being the wettest month (4.3") and July the driest (0.0").