Lake Forest, California climate: NOAA's gridded normals for the city, beside the nearest station records
NOAA's gridded 1991-2020 normals put Lake Forest's center at January lows of 47°F and July highs of 84°F, a yearly mean of 64.5°F and 12.7 inches of precipitation. No NOAA station keeps a record under the city's name. The nearest station record, Irvine (5 miles NW, 540 ft), has January lows of 49°F and July highs of 88°F.
87,159 people (Census Bureau 2024). Distances and directions are from the city's center.
- Jan 68° 47°
- Feb 68° 47°
- Mar 69° 49°
- Apr 72° 50°
- May 74° 54°
- Jun 79° 58°
- Jul 84° 62°
- Aug 86° 63°
- Sep 85° 61°
- Oct 79° 57°
- Nov 74° 50°
- Dec 68° 46°
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 Lake Forest's center.
What is each month like in Lake Forest?
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. | Irvine high | Irvine low |
|---|---|---|---|---|---|---|
| January | 68°F | 47°F | 57.5°F | 2.76 | 69°F | 49°F |
| February | 68°F | 47°F | 57.3°F | 3.31 | 71°F | 48°F |
| March | 69°F | 49°F | 58.9°F | 1.91 | 73°F | 50°F |
| April | 72°F | 50°F | 61.4°F | 0.78 | 76°F | 52°F |
| May | 74°F | 54°F | 64.3°F | 0.25 | 79°F | 56°F |
| June | 79°F | 58°F | 68.1°F | 0.05 | 83°F | 59°F |
| July | 84°F | 62°F | 72.7°F | 0.03 | 88°F | 62°F |
| August | 86°F | 63°F | 74.3°F | 0.01 | 90°F | 62°F |
| September | 85°F | 61°F | 72.9°F | 0.11 | 89°F | 62°F |
| October | 79°F | 57°F | 67.9°F | 0.49 | 84°F | 58°F |
| November | 74°F | 50°F | 62.0°F | 0.87 | 76°F | 53°F |
| December | 68°F | 46°F | 56.9°F | 2.12 | 68°F | 48°F |
In metric: a yearly mean of 18.1°C, January lows of 8°C, July highs of 29°C and 322 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 Lake Forest 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 |
|---|---|---|---|---|---|---|---|---|
| IrvineIrvine Ranch | 5 mi NW | 540 ft | 66.7°F | 49°F | 88°F | 13.1 | – | – |
| TustinTustin Irvine Ranch | 6 mi NW | 235 ft | 64.8°F | 43°F | 85°F | 14.1 | 0 | January 5 |
| Laguna Beach | 10 mi SW | 44 ft | 63.1°F | 44°F | 80°F | 12.7 | 0 | January 6 |
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 Lake Forest?
NOAA's grid gives no snow, frost dates or records, so these come from the nearest station record, Irvine (5 miles NW, 540 ft). NOAA publishes no snowfall normal for it; the nearest record that has one, Tustin (6 miles NW), gets 0 inches a year. Frost is rare there: NOAA gives no median frost date.
The USDA's 2023 Plant Hardiness Zone Map puts Lake Forest in zone 10b across its 2 ZIP code areas.
Over a year 87% of the sunlight that would reach the ground under clear skies gets through the clouds in the area (5.4 kWh per square metre a day, NASA POWER 2001-2020); August is the sunniest month (92%) and February the cloudiest (83%).
Irvine'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 Lake Forest; the nearest record's month pages have them.
Source: NOAA NCEI 1991-2020 normals, station USC00044303; 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 Lake Forest, ZIP code by ZIP code?
2 ZIP code areas lie wholly or partly in Lake Forest. On NOAA's grid 92610 is the warmest (64.9°F a year) and 92630 the coolest (64.5°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.