Antioch, California Weather
Coastal fog thickens at dawn. Day 77 of spring. Read this microseason across nine climate regions →
Antioch weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Partly Cloudy——87°59°—
- FridayJun 5Overcast——92°63°+5°
- SaturdayJun 6Overcast——82°50°-10°
- SundayJun 7Overcast——81°48°-1°
- MondayJun 8Light Rain14%0.15″63°51°-18°
- TuesdayJun 9Light Drizzle—0.04″67°55°+4°
- WednesdayJun 10Clear——85°52°+18°
Ozone at AQI 48 now. AQI down 9 over the last 6 hours (steady decline since this morning). With UV 9.9 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 63 by mid-afternoon.
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 48 now. With UV 9.9 peaking around 1 PM under clear skies, surface ozone likely climbs to AQI 63 by mid-afternoon.
- Present
- AQI 48
- UV peak
- 9.9 at 1 PM
- Sky at peak
- clear
- Projected peak
- AQI 63
PM × Wind × Precip
PM2.5/PM10 ratio 0.53 with 8 mph wind — characteristic of long-range haze transport rather than a local source.
- PM2.5/PM10
- 0.53
- 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
- 6:33 AM
- Moonset
- 4:20 PM
- In sign
- ♒︎ Aquarius
Coastal fog thickens at dawn
Antioch at a glance
- Today vs. normal: 7°F above the seasonal normal for this latitude
- Last frost: April 4 (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 | — | — |
| 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 stands as Antioch's warmest month with temperatures averaging around 76°F, while January brings the coldest conditions at roughly 48°F. January also delivers the heaviest rainfall at 2.7 inches, contrasting sharply with July's bone-dry 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
Antioch belongs to the hot-summer Mediterranean climate region, sharing similar temperature ranges, seasonal patterns, and growing conditions with other 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 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?
- Spring's final frost in Antioch usually occurs around mid-April, while the first fall frost returns around mid-November.
- What is the rainy season in Antioch?
- January stands as the wettest month, delivering about 2.7 inches of rain on average, while the city receives roughly 13 inches annually.
- What is the warmest month in Antioch?
- July typically brings the warmest temperatures, averaging about 76°F.
- What is the coldest month in Antioch?
- January typically delivers the coldest temperatures, averaging about 48°F.
- When can I start a vegetable garden in Antioch?
- 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 Antioch get?
- Antioch experiences about 30 rainy days per year on average.
- What hardiness zone is Antioch?
- Antioch's USDA hardiness zone depends on its lowest average winter temperature; the USDA's online lookup tool using the city ZIP code provides the current zone designation.
Climate
Antioch, California experiences a hot-summer Mediterranean climate zone. Temperatures hover near 48°F in January and climb to an average of 76°F in July, creating a 28°F seasonal swing.
Annual precipitation in Antioch totals about 13 inches, falling across roughly 30 rainy days throughout the year.
Geography shapes Antioch's weather patterns through its latitude at 38.0°N, proximity to large water bodies, and elevation. These factors determine what grows in the area, when frost threatens, and the daily weather patterns residents experience.