Hayward, California Weather
Ceanothus blooms again. Day 93 of summer. Read this microseason across nine climate regions →
Hayward weather forecast — hour by hour, 7-day outlook, NOAA radar
Conditions updated 7:24 AM PDT · Open-Meteo
- TodaySep 21Overcast——67°58°—
- TuesdaySep 22Overcast——71°57°+4°
- WednesdaySep 23Clear——78°55°+7°
- ThursdaySep 24Overcast——73°62°-5°
- FridaySep 25Overcast——71°61°-2°
- SaturdaySep 26Overcast——71°60°0°
- SundaySep 27Overcast——68°57°-3°
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 8.6 µg/m³ (AQI 48) with a 0.82 fine-to-coarse ratio and 4 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 8.6 µg/m³ (AQI 48) with a 0.82 fine-to-coarse ratio and 4 mph wind — combustion smoke trapped in stagnant air, not road dust.
- PM2.5/PM10
- 0.82
- 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
- 4:38 PM
- Moonset
- 1:43 AM
- In sign
- ♑︎ Capricorn
Ceanothus blooms again
Read this microseason across nine climate regions →
All 72 microseasons on the year wheel →
Hayward at a glance
- Today vs. normal: Today averages 63°F (high 67°F, low 58°F), 4°F below the 67°F normal for Sep 21
- Last frost: None in most years — 32°F in 45% of 1991–2020 years (NOAA station 4 km away)
- Microseason: Sep 21–25
- Planting calendar: September — plant lettuce, peas, spinach, radishes; harvest lettuce, peas, spinach, radishes, tomatoes, peppers, beans, summer squash, winter squash
16-Day Forecast — Hayward
- Mon67°58°1%
- Tue71°57°1%
- Wed78°55°0%
- Thu73°62°0%
- Fri71°61°0%
- Sat71°60°0%
- Sun68°57°1%
- Mon77°59°1%
- Tue85°65°1%
- Wed87°69°4%
- Thu89°71°1%
- Fri88°75°6%
- Sat90°74°0%
- Sun80°66°0%
- Mon74°60°0%
- Tue72°60°0%
Forecast data from Open-Meteo (CC BY 4.0).
Live wind & temperature near Hayward
Interactive wind and temperature map centered on Hayward — 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, and radishes; harvest lettuce, peas, spinach, radishes, tomatoes, peppers, beans, summer squash, and winter squash.
Sun & seasons in Hayward
Hayward sits in Alameda County, where the year’s longest day runs 14h 46m of daylight and its shortest just 9h 33m — a swing of +5h 13m 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 318 miles to the SE. The nearest town Hayward tracks is Fremont, roughly 9 miles to the SE.
Air quality in Hayward
Air quality in Hayward’s county has trended cleaner since 2020; its cleanest year on record was 2023 (median AQI 48). See the full air-quality history for Hayward.
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 | lettuce, peas, spinach, radishes |
| May | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes |
| June | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes, summer squash |
| July | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes, tomatoes, peppers, beans, summer 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 | 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 |
| December | lettuce, peas, spinach, radishes | lettuce, peas, spinach, radishes |
A year in weather
Hayward's warmest month is September (~67°F mean) and its coldest is December (~51°F). Rainfall peaks in December (3.2 inches) and bottoms out in July (0.0 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 51° | 2.9″ | 10 |
| February | 54° | 3.1″ | 9 |
| March | 56° | 2.4″ | 9 |
| April | 58° | 1.2″ | 6 |
| May | 61° | 0.6″ | 3 |
| June | 65° | 0.1″ | 1 |
| July | 66° | 0.0″ | 0 |
| August | 67° | 0.1″ | 0 |
| September | 67° | 0.1″ | 1 |
| October | 64° | 0.8″ | 3 |
| November | 56° | 1.5″ | 7 |
| December | 51° | 3.2″ | 10 |
Regional context
Similar climates Fairview, CA, Cherryland, CA, Union City, CA
In Hayward, NOAA NCEI 1991-2020 normals put January near 51°F and July near 66°F — a 15°F seasonal arc — with about 16 inches of precipitation over 59 rainy or snowy days.
Hayward's moisture rides winter storm tracks: December brings 3.2 inches over 10.0 wet days, while July sees only 0.0 inches across 0.1 days in the dry warm season. That groups Hayward with places like Fairview, CA, Cherryland, CA and Union City, CA on the same cool-season storm track.
Hard freezes are rare in Hayward: the coldest month averages 51°F, so Hayward's growing window runs most of the year. August is the hottest stretch near 67°F, pushing cool-season crops to the milder shoulder months. Hayward's rare cold nights chill open ground first.
Similar climates: Fairview, CA, Cherryland, CA, Union City, CA, San Lorenzo, CA, Ashland, CA.
Frequently asked
- When does it freeze in Hayward?
- Most years Hayward doesn't freeze: the nearest NOAA station reached 32°F in 45% of 1991–2020 years, so Hayward has no reliable frost date.
- What is the rainy season in Hayward?
- Hayward sees its heaviest rain in December (around 3.2 inches), part of roughly 16 inches a year.
- What is the warmest month in Hayward?
- September is Hayward's warmest month, averaging about 67°F.
- What is the coldest month in Hayward?
- Hayward bottoms out in December, with a mean near 51°F.
- When can I start a vegetable garden in Hayward?
- Hayward has no frost date to wait for, so sowing runs year-round; lettuce and greens do best when Hayward's coldest month settles near 51°F.
- How many rainy days does Hayward get?
- Hayward averages about 59 days with measurable rain or snow each year.
- What hardiness zone is Hayward?
- Hayward sits in the USDA zone set by December lows near 51°F; the USDA ZIP tool gives the band.
- What is the 10-day forecast for Hayward?
- Hayward'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 Hayward?
- See this week's day-by-day rain chances for Hayward in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Hayward?
- Current conditions for Hayward and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Hayward forecast updated?
- The Hayward forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Hayward?
- Today's sunrise and sunset times for Hayward 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 Hayward?
- The next few days in Hayward's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Hayward sits at 37.6°N; its climate zone is hot-summer Mediterranean (Köppen approximation).
ZIP codes in Hayward
- 94540
- 94541
- 94542
- 94543
- 94544
- 94545
- 94557
- 94587