Santa Ana, California Weather
Coastal fog thickens at dawn. Day 77 of spring. Read this microseason across nine climate regions →
Santa Ana weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Foggy——75°63°—
- FridayJun 5Overcast——74°62°-1°
- SaturdayJun 6Overcast——72°61°-2°
- SundayJun 7Overcast——73°63°+1°
- MondayJun 8Mostly Clear——72°62°-1°
- TuesdayJun 9Overcast——72°63°0°
- WednesdayJun 10Mostly Clear——73°61°+1°
PM2.5/PM10 ratio 0.61 with 7 mph wind — characteristic of long-range haze transport rather than a local source. AQI flat over the last 6 hours (within ±3 points).
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
What's driving it
Ozone × UV × Sky
Ozone at AQI 55 now. With UV 9.8 peaking around 1 PM under partly cloudy skies, surface ozone likely climbs to AQI 51 by mid-afternoon.
- Present
- AQI 55
- UV peak
- 9.8 at 1 PM
- Sky at peak
- partly cloudy
- Projected peak
- AQI 51
PM × Wind × Precip
PM2.5/PM10 ratio 0.61 with 7 mph wind — characteristic of long-range haze transport rather than a local source.
- PM2.5/PM10
- 0.61
- Wind
- light
- Recent rain
- 0h in last 6h
- Pattern
- transport
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).
A summer fog for fair, a winter fog for rain.
- Moonrise
- 6:04 AM
- Moonset
- 4:15 PM
- In sign
- ♒︎ Aquarius
Coastal fog thickens at dawn
Santa Ana at a glance
- Today vs. normal: 8°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 4, 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
August brings Santa Ana's peak heat with mean temperatures around 75°F, while December delivers the year's coldest weather at about 58°F. Rain follows a Mediterranean pattern, peaking in February at 3.2 inches and disappearing almost entirely in August at 0.0 inches.
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 59° | 2.9″ | 5 |
| February | 59° | 3.2″ | 5 |
| March | 62° | 1.7″ | 3 |
| April | 64° | 0.8″ | 2 |
| May | 66° | 0.3″ | 1 |
| June | 70° | 0.1″ | 0 |
| July | 74° | 0.0″ | 0 |
| August | 75° | 0.0″ | 0 |
| September | 74° | 0.1″ | 0 |
| October | 69° | 0.5″ | 1 |
| November | 63° | 0.8″ | 2 |
| December | 58° | 2.2″ | 4 |
Regional context
Local climate places Santa Ana squarely within the hot-summer Mediterranean zone, where it shares temperature ranges, seasonal rhythms, and growing conditions with surrounding cities in the region.
Similar climates: Los Angeles, CA, San Francisco, CA, San Diego, CA, Riverside, CA, Sacramento, CA.
Naturalist notes
California poppies begin their spring bloom in late March, painting hillsides orange as winter rains fade.
Red-winged blackbirds establish territories in marsh edges during April, their distinctive calls marking the shift toward warmer months.
Frequently asked
- When does it freeze in Santa Ana?
- Mid-March typically marks Santa Ana's last spring frost, while the first fall frost usually arrives around mid-December.
- What is the rainy season in Santa Ana?
- February brings the heaviest rainfall at about 3.2 inches on average, contributing to the city's annual total of roughly 13 inches.
- What is the warmest month in Santa Ana?
- August typically records the year's highest temperatures, averaging about 75°F.
- What is the coldest month in Santa Ana?
- December usually brings the coldest weather, with temperatures averaging about 58°F.
- When can I start a vegetable garden in Santa Ana?
- Cool-season crops like peas and lettuce can go in the ground around the last spring frost in mid-March, while warm-season crops such as tomatoes and peppers should wait 1–2 weeks after.
- How many rainy days does Santa Ana get?
- Santa Ana sees precipitation on about 22 days per year on average.
- What hardiness zone is Santa Ana?
- Santa Ana'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.
Climate
Santa Ana, California experiences a hot-summer Mediterranean climate zone. Winter temperatures in January typically hover near 59°F, while July averages reach 74°F — creating a 15°F seasonal swing.
Annual precipitation in Santa Ana totals about 13 inches, falling across roughly 22 rainy days throughout the year.
Geography shapes Santa Ana's weather patterns through its latitude at 33.7°N, proximity to large water bodies, and elevation. These factors determine what grows locally, when frost threatens, and how daily weather unfolds.