Weather in San Francisco, California
Fog and sun in daily rhythm. Day 59 of spring. Read this microseason across nine climate regions →
When the dew is on the grass, rain will never come to pass.
- Moonrise
- 1:11 PM
- Moonset
- 3:48 AM
- In sign
- ♉︎ Taurus
Fog and sun in daily rhythm
San Francisco at a glance
- Today vs. normal: NaN°F below the seasonal normal for this latitude
- Last frost: April 3 (climatological average for this latitude)
- Microseason: 28 of 72, May 16–20
- Planting window: Direct sow okra, melons, and southern peas. Thin carrot rows.
Right now in the garden
Warm-season window is open
As of May 17, the last spring frost has passed for most years. Transplant tomatoes, peppers, eggplants, basil, and cucurbits (cucumbers, squash, melons) now. Direct-sow beans and corn into warm soil.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | — | — |
| February | — | — |
| March | — | — |
| April | lettuce, peas, spinach, radishes | — |
| May | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, radishes |
| July | tomatoes, peppers, beans, squash | tomatoes, beans, summer squash |
| August | — | tomatoes, beans, summer squash |
| September | fall brassicas, garlic (overwinter), carrots | tomatoes, beans, summer squash |
| October | fall brassicas, garlic (overwinter), carrots | winter squash, tomatoes (last) |
| November | — | — |
| December | — | — |
A year in weather
September marks San Francisco's warmest month at roughly 63°F mean temperature, while January brings the coldest conditions at around 52°F. Rain follows a predictable pattern, peaking in December with 4.8 inches and disappearing entirely in July at 0.0 inches.
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 52° | 4.4″ | 8 |
| February | 54° | 4.4″ | 8 |
| March | 56° | 3.1″ | 7 |
| April | 56° | 1.6″ | 4 |
| May | 58° | 0.7″ | 2 |
| June | 60° | 0.2″ | 1 |
| July | 60° | 0.0″ | 0 |
| August | 62° | 0.1″ | 0 |
| September | 63° | 0.1″ | 0 |
| October | 62° | 0.9″ | 2 |
| November | 57° | 2.6″ | 5 |
| December | 53° | 4.8″ | 8 |
Regional context
Climatically, San Francisco belongs to the hot-summer Mediterranean zone, sharing temperature ranges, seasonal rhythms, and growing conditions with other cities in this regional climate pattern.
Similar climates: Los Angeles, CA, San Diego, CA, Riverside, CA, Sacramento, CA, San Jose, CA.
Naturalist notes
Late May brings the peak flowering of California poppies across hillsides, their orange petals opening wide during warm afternoon hours.
Anna's hummingbirds begin their courtship displays in February, with males performing dramatic dive flights that produce distinctive whistling sounds.
Frequently asked
- When does it freeze in San Francisco?
- Spring's final frost usually occurs around mid-April in San Francisco, while the season's first frost returns around mid-November.
- What is the rainy season in San Francisco?
- December delivers the heaviest rainfall, averaging 4.8 inches, while the city's total annual precipitation reaches about 23 inches.
- What is the warmest month in San Francisco?
- September typically brings the year's highest temperatures, with averages around 63°F.
- What is the coldest month in San Francisco?
- January registers as the coldest month, averaging approximately 52°F.
- When can I start a vegetable garden in San Francisco?
- Plant cool-season vegetables like peas and lettuce around the final spring frost in mid-April. Wait 1–2 weeks longer before planting warm-season crops such as tomatoes and peppers.
- How many rainy days does San Francisco get?
- San Francisco records approximately 45 rainy days each year.
- What hardiness zone is San Francisco?
- USDA hardiness zones depend on average minimum winter temperatures. Use the USDA's online zone finder with San Francisco ZIP codes for current official designations.
Climate
San Francisco, California experiences a hot-summer Mediterranean climate zone. Winter temperatures in January hover near 52°F, while July averages 60°F — creating just an 8°F seasonal swing.
Annual precipitation totals about 23 inches across roughly 45 rainy days throughout the year.
Weather patterns here stem from the city's latitude at 37.8°N, its proximity to large water bodies, and local elevation changes. These factors determine what plants thrive, when frost threatens, and how daily weather unfolds.