Santa Ana, California Weather
Ceanothus blooms again. Day 93 of summer. Read this microseason across nine climate regions →
Santa Ana weather forecast — hour by hour, 7-day outlook, NOAA radar
Conditions updated 12:30 AM PDT · Open-Meteo
- TodaySep 21Overcast later——78°68°—
- TuesdaySep 22Overcast——78°66°0°
- WednesdaySep 23Clear——81°69°+3°
- ThursdaySep 24Clear——83°70°+2°
- FridaySep 25Clear——87°72°+4°
- SaturdaySep 26Overcast——89°74°+2°
- SundaySep 27Overcast——88°74°-1°
Air quality now AQI 51 · Moderate
AQI 51 (Moderate), driven by PM2.5. AQI flat over the last 6 hours (within ±3 points). PM2.5 at 9.4 µg/m³ (AQI 52) with a 0.70 fine-to-coarse ratio and 3 mph wind — combustion smoke trapped in stagnant 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
Ozone × UV × Sky
Ozone at AQI 38 now. With UV 3.3 peaking around 1 PM under partly cloudy skies, surface ozone likely climbs to AQI 12.
- Present
- AQI 38
- UV peak
- 3.3 at 1 PM
- Sky at peak
- partly cloudy
- Projected peak
- AQI 12
PM × Wind × Precip
PM2.5 at 9.4 µg/m³ (AQI 52) with a 0.70 fine-to-coarse ratio and 3 mph wind — combustion smoke trapped in stagnant air, not road dust.
- PM2.5/PM10
- 0.70
- 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).
September dries up ditches or breaks down bridges.
- Moonrise
- 4:10 PM
- Moonset
- 1:36 AM
- In sign
- ♑︎ Capricorn
Ceanothus blooms again
Read this microseason across nine climate regions →
All 72 microseasons on the year wheel →
Santa Ana at a glance
- Today vs. normal: Today averages 73°F (high 78°F, low 68°F), 2°F above the 71°F normal for Sep 21
- Last frost: None in most years — 32°F in 3% of 1991–2020 years (NOAA station 2 km away)
- Microseason: Sep 21–25
- Planting calendar: September — plant lettuce, peas, spinach, radishes, beans, squash; harvest lettuce, peas, spinach, radishes, tomatoes, peppers, beans, summer squash, winter squash
15-Day Forecast — Santa Ana
- Mon78°68°1%
- Tue78°66°0%
- Wed81°69°0%
- Thu83°70°1%
- Fri87°72°0%
- Sat89°74°0%
- Sun88°74°4%
- Mon93°75°7%
- Tue89°80°11%
- Wed94°73°12%
- Thu77°71°3%
- Fri86°72°3%
- Sat88°75°6%
- Sun94°77°5%
- Mon84°80°3%
Forecast data from Open-Meteo (CC BY 4.0).
Live wind & temperature near Santa Ana
Interactive wind and temperature map centered on Santa Ana — it loads in your browser. Open the full weather map.
Right now in the garden
Year-round growing
As of September 21, sowing here runs through the year. Freezes are uncommon, so there is no frost date to plan around; heat and rainfall set the calendar instead. This city's planting calendar for September: plant lettuce, peas, spinach, radishes, beans, and squash; harvest lettuce, peas, spinach, radishes, tomatoes, peppers, beans, summer squash, and winter squash.
Sun & seasons in Santa Ana
Santa Ana sits in Orange County, where the year’s longest day runs 14h 24m of daylight and its shortest just 9h 54m — a swing of +4h 29m between the June and December solstices. Clocks spring forward on Sunday, March 8, 2026 and fall back on Sunday, November 1, 2026.
Los Angeles, the state’s largest city, lies about 40 miles to the NW. The nearest town Santa Ana tracks is Garden Grove, roughly 5 miles to the WNW.
Air quality in Santa Ana
Air quality in Santa Ana’s county has held roughly steady since 2020; its cleanest year on record was 2023 (median AQI 52). See the full air-quality history for Santa Ana.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | lettuce, peas, spinach, radishes | lettuce, peas, spinach, radishes |
| February | lettuce, peas, spinach, radishes | lettuce, peas, spinach, radishes |
| March | lettuce, peas, spinach, radishes | lettuce, peas, spinach, radishes |
| April | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes |
| May | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes, summer squash |
| June | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, summer squash |
| July | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, summer squash, winter squash |
| August | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, summer squash, winter squash |
| September | lettuce, peas, spinach, radishes, beans, squash | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, summer squash, winter squash |
| October | lettuce, peas, spinach, radishes | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, summer squash, winter squash |
| November | lettuce, peas, spinach, radishes | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, summer squash, winter squash |
| December | lettuce, peas, spinach, radishes | lettuce, peas, spinach, radishes |
A year in weather
The year in Santa Ana tops out in August (~73°F) and dips lowest in January (~54°F), with February wettest at 2.5 inches and August driest at 0.0 inches.
| Month | Mean temp | Precip |
|---|---|---|
| January | 54° | 2.3″ |
| February | 56° | 2.5″ |
| March | 58° | 2.0″ |
| April | 61° | 0.9″ |
| May | 64° | 0.3″ |
| June | 68° | 0.0″ |
| July | 72° | 0.1″ |
| August | 73° | 0.0″ |
| September | 72° | 0.0″ |
| October | 68° | 0.3″ |
| November | 60° | 1.1″ |
| December | 54° | 1.8″ |
Regional context
Similar climates Tustin, CA, Fountain Valley, CA, Costa Mesa, CA
By modelled 1991-2020 normals (EC_Earth3P_HR model via Open-Meteo), Santa Ana sees 54°F Januarys and 72°F Julys, an 18°F range, plus around 11.3 inches of precipitation.
Precipitation in Santa Ana peaks in the cool season: February averages 2.5 inches, while August bottoms out at 0.0 inches. It is a winter-storm rhythm Santa Ana shares with places like Tustin, CA, Fountain Valley, CA and Costa Mesa, CA.
Freezes are uncommon in Santa Ana, where the coldest month averages 54°F; cool-season crops grow fall through spring. Summer heat in August (about 73°F) is the binding constraint, not cold. Santa Ana's rare cold nights chill open ground first.
Similar climates: Tustin, CA, Fountain Valley, CA, Costa Mesa, CA, North Tustin, CA, Garden Grove, CA.
Frequently asked
- When does it freeze in Santa Ana?
- Santa Ana freezes in fewer than half of years — 3% of 1991–2020 years at the nearest NOAA station — so Santa Ana has no typical frost date.
- What is the rainy season in Santa Ana?
- Rainfall in Santa Ana peaks in February near 2.5 inches, out of about 11 inches annually.
- What is the warmest month in Santa Ana?
- Santa Ana peaks in August, when the mean runs near 73°F.
- What is the coldest month in Santa Ana?
- January is Santa Ana's coldest month, averaging about 54°F.
- When can I start a vegetable garden in Santa Ana?
- Any season works in Santa Ana: without a reliable freeze, Santa Ana's heat, not frost, decides when greens and tomatoes do best.
- What hardiness zone is Santa Ana?
- Because Santa Ana bottoms near 54°F in January, that winter low sets Santa Ana's USDA zone — verify by ZIP.
- What is the 10-day forecast for Santa Ana?
- Santa Ana's extended outlook — daily high and low temperatures and precipitation chances for each upcoming day — is in the daily forecast above.
- Will it rain this week in Santa Ana?
- See this week's day-by-day rain chances for Santa Ana in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Santa Ana?
- Current conditions for Santa Ana and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Santa Ana forecast updated?
- The Santa Ana forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Santa Ana?
- Today's sunrise and sunset times for Santa Ana are in the Almanac section above, along with civil dawn, civil dusk, and day length. Day length is longest near the summer solstice and shortest near the winter solstice.
- How accurate is the weather forecast for Santa Ana?
- The next few days in Santa Ana's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Santa Ana sits at 33.7°N; its climate zone is hot-summer Mediterranean (Köppen approximation).
ZIP codes in Santa Ana
- 92701
- 92702
- 92703
- 92704
- 92705
- 92706
- 92707
- 92735
- 92799