Weather in Fairfield, 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
- 1:08 PM
- Moonset
- 3:48 AM
- In sign
- ♉︎ Taurus
Fog and sun in daily rhythm
Fairfield at a glance
- Today vs. normal: NaN°F below the seasonal normal for this latitude
- Last frost: April 6 (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
July brings Fairfield's peak warmth with mean temperatures around 74°F, while December delivers the coldest conditions at roughly 48°F. Rain follows the opposite pattern — December brings the heaviest precipitation at 5.4 inches, while July typically sees 0.0 inches.
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 49° | 4.7″ | 8 |
| February | 52° | 5.0″ | 8 |
| March | 56° | 3.3″ | 7 |
| April | 60° | 1.5″ | 3 |
| May | 65° | 0.7″ | 2 |
| June | 71° | 0.2″ | 0 |
| July | 74° | 0.0″ | 0 |
| August | 74° | 0.0″ | 0 |
| September | 72° | 0.1″ | 0 |
| October | 65° | 1.1″ | 2 |
| November | 55° | 2.5″ | 5 |
| December | 48° | 5.4″ | 8 |
Regional context
As part of the hot-summer Mediterranean climate region, Fairfield shares temperature ranges, seasonal patterns, and growing conditions with other nearby cities in this climate zone.
Similar climates: Los Angeles, CA, San Francisco, CA, San Diego, CA, Riverside, CA, Sacramento, CA.
Naturalist notes
Late May brings the distinctive calls of Western Bluebirds as they establish territories in oak woodlands around Fairfield.
California poppies reach peak bloom across the region's grasslands during April and early May.
Frequently asked
- When does it freeze in Fairfield?
- Spring's final frost in Fairfield typically occurs around mid-April, while the first fall frost returns around mid-November.
- What is the rainy season in Fairfield?
- December stands as the wettest month, delivering about 5.4 inches of rain on average, contributing to the city's annual total of roughly 25 inches.
- What is the warmest month in Fairfield?
- July typically registers as the warmest month, with temperatures averaging about 74°F.
- What is the coldest month in Fairfield?
- December usually brings the coldest temperatures, averaging about 48°F.
- When can I start a vegetable garden in Fairfield?
- Cool-season crops like peas and lettuce can be planted around the last spring frost in mid-April, while warm-season crops such as tomatoes and peppers should wait 1–2 weeks after.
- How many rainy days does Fairfield get?
- Fairfield experiences about 42 rainy days per year on average.
- What hardiness zone is Fairfield?
- Fairfield's USDA hardiness zone depends on its lowest average winter temperature; the USDA's online lookup tool can provide the current zone designation using the city ZIP code.
Climate
Fairfield, California experiences a hot-summer Mediterranean climate. Winter temperatures in January hover near 49°F, while July brings averages of 74°F — creating a 25°F seasonal swing.
Annual precipitation totals about 25 inches, falling across roughly 42 rainy days throughout the year.
Geography shapes Fairfield's weather patterns through its latitude of 38.3°N, proximity to large water bodies, and elevation. These factors determine growing conditions, frost timing, and daily weather variations.