Lake Forest, California Weather
Coastal fog thickens at dawn. Day 78 of spring. Read this microseason across nine climate regions →
Lake Forest weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 5Foggy——81°60°—
- SaturdayJun 6Overcast——73°60°-8°
- SundayJun 7Clear——78°59°+5°
- MondayJun 8Clear——81°59°+3°
- TuesdayJun 9Clear——82°62°+1°
- WednesdayJun 10Partly Cloudy——81°64°-1°
- ThursdayJun 11Clear——85°63°+4°
AQI 53 (Moderate), driven by PM2.5. AQI down 18 over the last 6 hours — air quality is improving sharply. PM2.5 at 11.3 µg/m³ (AQI 55) with a 0.68 fine-to-coarse ratio and 2 mph wind — combustion smoke trapped in calm air, not road dust.
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
What's driving it
PM × Wind × Precip
PM2.5 at 11.3 µg/m³ (AQI 55) with a 0.68 fine-to-coarse ratio and 2 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.68
- Wind
- calm
- Recent rain
- 0h in last 6h
- Pattern
- stagnant smoke
Trends
Seven days of AQI and PM2.5.
Hourly air-quality data from the Copernicus Atmosphere Monitoring Service, charted across the past and next several days. Dashed lines mark the AQI breakpoints at 50 (Good → Moderate) and 100 (Moderate → Unhealthy for Sensitive Groups).
The higher the clouds, the finer the weather.
- Moonrise
- 6:39 AM
- Moonset
- 5:16 PM
- In sign
- ♒︎ Aquarius
Coastal fog thickens at dawn
Lake Forest at a glance
- Today vs. normal: 19°F below the seasonal normal for this latitude
- Last frost: March 9 (climatological average for this latitude)
- Microseason: Jun 1–5
- Planting window: Harvest spring lettuce before it bolts. Sow heat-tolerant greens.
Right now in the garden
Peak growing season
As of June 5, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | — | — |
| February | — | — |
| March | lettuce, peas, spinach, radishes | — |
| April | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | — |
| May | tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| July | — | tomatoes, beans, summer squash |
| August | — | tomatoes, beans, summer squash |
| September | — | tomatoes, beans, summer squash |
| October | fall brassicas, garlic (overwinter), carrots | winter squash, tomatoes (last) |
| November | fall brassicas, garlic (overwinter), carrots | — |
| December | — | — |
A year in weather
Lake Forest's warmest month is August (~77°F mean) and its coldest is December (~59°F). Rainfall peaks in January (3.2 inches) and bottoms out in August (0.0 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 60° | 3.2″ | 5 |
| February | 60° | 3.0″ | 5 |
| March | 63° | 1.8″ | 3 |
| April | 65° | 0.7″ | 2 |
| May | 68° | 0.4″ | 1 |
| June | 72° | 0.1″ | 0 |
| July | 76° | 0.1″ | 0 |
| August | 77° | 0.0″ | 0 |
| September | 76° | 0.1″ | 0 |
| October | 71° | 0.6″ | 1 |
| November | 65° | 1.0″ | 2 |
| December | 59° | 2.4″ | 4 |
Regional context
Lake Forest belongs to a hot-summer Mediterranean climate region — a cohort of cities sharing similar temperature ranges, seasonal patterns, and growing conditions.
Similar climates: Los Angeles, CA, San Francisco, CA, San Diego, CA, Riverside, CA, Sacramento, CA.
Naturalist notes
By late May the toyon shrubs on south-facing slopes finish flowering and set small green berries that will ripen slowly through summer.
Barn swallows return to nest under bridges and eaves, their arrival tracking daytime temperatures that reliably stay above 60°F.
Frequently asked
- When does it freeze in Lake Forest?
- Lake Forest's last spring frost usually lands around mid-March; the first fall frost arrives near mid-December.
- What is the rainy season in Lake Forest?
- January is the wettest month, averaging about 3.2 inches of rain, and the city receives roughly 14 inches annually.
- What is the warmest month in Lake Forest?
- August is typically the warmest month, averaging about 77°F.
- What is the coldest month in Lake Forest?
- December is typically the coldest month, averaging about 59°F.
- When can I start a vegetable garden in Lake Forest?
- Cool-season crops (peas, lettuce) can be sown around the last spring frost in mid-March; warm-season crops (tomatoes, peppers) wait until 1–2 weeks after.
- How many rainy days does Lake Forest get?
- Lake Forest averages about 23 rainy days per year.
- What hardiness zone is Lake Forest?
- Lake Forest's USDA hardiness zone is set by the lowest average winter temperature; check the USDA's online lookup using the city ZIP for the current zone designation.
Climate
Lake Forest, California lies in a hot-summer Mediterranean climate zone. January temperatures sit near 60°F while July averages 76°F — a 16°F seasonal swing.
Over the year the city collects about 14 inches of precipitation, falling across roughly 23 rainy days.
Latitude (33.7°N), nearby bodies of water, and local elevation set the annual rhythm. These factors shape what grows, signal when frost is likely, and write the daily weather story.