Antioch, California Weather
August begins in scorching stillness. Day 43 of summer. Read this microseason across nine climate regions →
Antioch weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayAug 2Clear——99°65°—
- MondayAug 3Clear——100°65°+1°
- TuesdayAug 4Clear——102°63°+2°
- WednesdayAug 5Clear——102°63°0°
- ThursdayAug 6Clear——103°62°+1°
- FridayAug 7Clear——105°64°+2°
- SaturdayAug 8Clear——107°65°+2°
AQI 51 (Moderate), driven by PM2.5. AQI flat over the last 6 hours (within ±3 points). PM2.5 at 8.2 µg/m³ (AQI 46) with a 0.81 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
PM × Wind × Precip
PM2.5 at 8.2 µg/m³ (AQI 46) with a 0.81 fine-to-coarse ratio and 3 mph wind — combustion smoke trapped in stagnant air, not road dust.
- PM2.5/PM10
- 0.81
- 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).
Red sky at night, sailor's delight.
- Moonrise
- 9:52 PM
- Moonset
- 10:17 AM
- In sign
- ♓︎ Pisces
August begins in scorching stillness
Antioch at a glance
- Today vs. normal: 3°F above the seasonal normal for this latitude
- Last frost: April 4 (climatological average for this latitude)
- Microseason: Aug 1–5
- Planting window: Sow fall peas. Start kale and collard seedlings for fall.
ZIP codes: 94509, 94531
16-Day Forecast — Antioch
- Sun99°65°0%
- Mon100°65°0%
- Tue102°63°0%
- Wed102°63°0%
- Thu103°62°0%
- Fri105°64°0%
- Sat107°65°0%
- Sun104°63°0%
- Mon96°58°0%
- Tue96°58°0%
- Wed96°58°1%
- Thu97°57°3%
- Fri97°59°0%
- Sat95°59°0%
- Sun97°56°3%
- Mon101°57°3%
Forecast data from Open-Meteo (CC BY 4.0).
Live wind & temperature near Antioch
Right now in the garden
Peak growing season
As of August 2, 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.
Sun & seasons in Antioch
Antioch sits in Contra Costa County, where the year’s longest day runs 14h 48m of daylight and its shortest just 9h 31m — a swing of +5h 17m 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 327 miles to the SE. The nearest town Antioch tracks is Concord, roughly 11 miles to the W.
Air quality in Antioch’s county has held roughly steady since 2020; its cleanest year on record was 2021 (median AQI 47). See the full air-quality history for Antioch.
Microseason · August 1–5
August begins in scorching stillness
Calm days dominate early August; temperatures peak; the entire ecosystem is in survival mode.
Day 214 of 365 · Wedge 43 of 72
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
In Antioch, July runs warmest near 76°F and January coldest around 48°F, while January is the wettest month (2.7 inches) and July the driest (0.0 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 48° | 2.7″ | 6 |
| February | 52° | 2.4″ | 6 |
| March | 57° | 1.9″ | 5 |
| April | 61° | 0.9″ | 2 |
| May | 67° | 0.4″ | 1 |
| June | 73° | 0.1″ | 0 |
| July | 76° | 0.0″ | 0 |
| August | 75° | 0.0″ | 0 |
| September | 73° | 0.1″ | 0 |
| October | 66° | 0.4″ | 1 |
| November | 55° | 1.2″ | 3 |
| December | 48° | 2.5″ | 6 |
Regional context
In Antioch, NOAA NCEI 1991-2020 normals put January near 48°F and July near 76°F — a 28°F seasonal arc — with about 12.6 inches of precipitation over 30 rainy or snowy days.
Cool-season fronts carry Antioch's rain: January logs 2.7 inches on 6.4 days, against July's 0.0 inches on 0.0 — winter does the heavy lifting in Antioch. That groups Antioch with places like Brentwood, CA, Oakley, CA and Pittsburg, CA on the same cool-season storm track.
With a coldest-month mean of 48°F, Antioch stays mostly frost-free and grows year-round. The July peak near 76°F is Antioch's real limit, pushing cool-season vegetables to spring and fall. Antioch's coastal lots stay 4-7°F milder overnight than Antioch's inland parcels.
Similar climates: Brentwood, CA, Oakley, CA, Pittsburg, CA, Clayton, CA, Knightsen, CA.
Naturalist notes
Late May brings the peak blooming period for California poppies across the hillsides surrounding Antioch.
Red-winged blackbirds establish their territories in the marsh areas during April, their distinctive calls echoing through the wetlands.
Frequently asked
- When does it freeze in Antioch?
- Antioch's last spring frost lands near mid-April, and in Antioch the first fall frost follows around mid-November.
- What is the rainy season in Antioch?
- Rainfall in Antioch peaks in January near 2.7 inches, out of about 13 inches annually.
- What is the warmest month in Antioch?
- The warmest stretch in Antioch comes in July, around 76°F on average.
- What is the coldest month in Antioch?
- On average January is the chilliest month in Antioch, about 48°F.
- When can I start a vegetable garden in Antioch?
- Time tomatoes in Antioch for two weeks after mid-April; peas and greens start at Antioch's frost line.
- How many rainy days does Antioch get?
- Antioch averages about 30 days with measurable rain or snow each year.
- What hardiness zone is Antioch?
- Antioch's USDA zone comes from its January mean (48°F); enter the ZIP on the USDA lookup for the number.
- What is the 10-day forecast for Antioch?
- Antioch'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 Antioch?
- See this week's day-by-day rain chances for Antioch in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Antioch?
- Current conditions for Antioch and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Antioch forecast updated?
- The Antioch forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Antioch?
- Today's sunrise and sunset times for Antioch 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 Antioch?
- The next few days in Antioch's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Climate
Antioch, California has a hot-summer Mediterranean climate: January averages roughly 48°F, July about 76°F, 28°F between them.
In a typical year Antioch records about 13 inches of precipitation on around 30 days.
At 38.0°N, Antioch's 28°F summer-to-winter swing sets when Antioch's gardens wake and when frost returns.
ZIP codes in Antioch
- 94531
- 94509