Folsom, California climate: NOAA's gridded normals for the city, beside the nearest station records
NOAA's gridded 1991-2020 normals put Folsom's center at January lows of 38°F and July highs of 95°F, a yearly mean of 62.2°F and 23.3 inches of precipitation. No NOAA station keeps a record under the city's name. The nearest station record, Auburn (17 miles N, 1,292 ft), has January lows of 38°F and July highs of 93°F.
88,091 people (Census Bureau 2024). Distances and directions are from the city's center.
- Jan 56° 38°
- Feb 61° 41°
- Mar 66° 44°
- Apr 72° 46°
- May 80° 52°
- Jun 89° 57°
- Jul 95° 61°
- Aug 94° 60°
- Sep 90° 57°
- Oct 79° 50°
- Nov 65° 43°
- Dec 56° 38°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
The months above are NOAA's gridded normals at Folsom's center.
What is each month like in Folsom?
NOAA's grid estimates the normals every 5 km or so from the stations around each point, terrain included. It smooths between stations, so night lows at the heart of a large city can run warmer than the grid shows: at five big-city airports we compared, the grid's highs were within about 1°F of the station and its lows 1-6°F cooler. The nearest record's high and low are beside each month.
| Month | High | Low | Mean | Precip. | Auburn high | Auburn low |
|---|---|---|---|---|---|---|
| January | 56°F | 38°F | 47.3°F | 4.67 | 56°F | 38°F |
| February | 61°F | 41°F | 51.2°F | 4.30 | 59°F | 40°F |
| March | 66°F | 44°F | 54.9°F | 3.47 | 63°F | 42°F |
| April | 72°F | 46°F | 59.1°F | 2.14 | 68°F | 45°F |
| May | 80°F | 52°F | 66.0°F | 1.11 | 77°F | 52°F |
| June | 89°F | 57°F | 73.3°F | 0.25 | 86°F | 58°F |
| July | 95°F | 61°F | 78.0°F | 0.01 | 93°F | 63°F |
| August | 94°F | 60°F | 77.0°F | 0.03 | 92°F | 63°F |
| September | 90°F | 57°F | 73.4°F | 0.12 | 87°F | 60°F |
| October | 79°F | 50°F | 64.6°F | 1.03 | 77°F | 52°F |
| November | 65°F | 43°F | 54.3°F | 2.31 | 64°F | 43°F |
| December | 56°F | 38°F | 47.3°F | 3.92 | 56°F | 37°F |
In metric: a yearly mean of 16.8°C, January lows of 4°C, July highs of 35°C and 593 mm of precipitation a year.
Source: NOAA NCEI U.S. Monthly Gridded Climate Normals 1991-2020 (nClimGrid, accession 0245564); NOAA NCEI 1991-2020 station normals. The grid cell holding the city's Census center point.
What do the station records around Folsom say?
Each row is a NOAA station's own 1991-2020 normals, with the snow and frost dates the grid does not give. A record downhill or nearer the coast than the city can run warmer, one uphill cooler: compare the elevations.
| Record | Where | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Auburn | 17 mi N | 1,292 ft | 61.2°F | 38°F | 93°F | 36.1 | – | February 25 |
| Placerville | 17 mi E | 1,850 ft | 59.8°F | 34°F | 94°F | – | – | March 31 |
| SacramentoSacramento Airport Asos | 22 mi SW | 15 ft | 61.8°F | 39°F | 93°F | 18.1 | – | February 2 |
Source: NOAA NCEI 1991-2020 U.S. Climate Normals; place center and population: Census Bureau 2024. Last frost: the median last spring date of 32°F.
How much snow, how late a frost, what zone and how much sun in Folsom?
NOAA's grid gives no snow, frost dates or records, so these come from the nearest station record, Auburn (17 miles N, 1,292 ft). NOAA publishes no snowfall normal for it; the nearest record that has one, Sacramento (5 mi ESE) (17 miles away), gets 0 inches a year. The last spring frost (32°F) comes after February 25 in half of years and the first autumn frost before December 5. Its record high is 113°F (1972) and its record low 16°F (1972) (kept since 1905).
The USDA's 2023 Plant Hardiness Zone Map puts Folsom in zone 9b across its 2 ZIP code areas.
Over a year 89% of the sunlight that would reach the ground under clear skies gets through the clouds in the area (5.2 kWh per square metre a day, NASA POWER 2001-2020); July is the sunniest month (98%) and January the cloudiest (70%).
Auburn's page has its months, frost probabilities, records by month and recent years. NOAA's grid has monthly figures only, so there are no day-by-day month pages for Folsom; the nearest record's month pages have them.
Source: NOAA NCEI 1991-2020 normals, station USC00040383; records: ACIS; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; sunshine: NASA POWER.
How does the climate vary across Folsom, ZIP code by ZIP code?
2 ZIP code areas lie wholly or partly in Folsom. On NOAA's grid 95630 is the warmest (62.2°F a year) and 95671 the coolest (62.1°F), so the city is nearly uniform. Each row also names the nearest station record and its frost dates.
Source: Census Bureau 2020 ZCTA-to-place relationship file and ZCTA centers; NOAA NCEI gridded and station normals, 1991-2020. A ZIP area counts when at least a tenth of its land (and 0.5 km²) is in the city; its figures are the grid cell at its center; frost dates are the nearest record's medians of 32°F.