Fremont, California Weather
Ceanothus blooms again. Day 93 of summer. Read this microseason across nine climate regions →
Fremont weather forecast — hour by hour, 7-day outlook, NOAA radar
Conditions updated 7:23 AM PDT · Open-Meteo
- TodaySep 21Overcast——70°58°—
- TuesdaySep 22Overcast——73°55°+3°
- WednesdaySep 23Clear——85°56°+12°
- ThursdaySep 24Overcast——81°62°-4°
- FridaySep 25Overcast——75°61°-6°
- SaturdaySep 26Partly Cloudy——79°59°+4°
- SundaySep 27Overcast——76°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 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 8.6 µg/m³ (AQI 48) with a 0.82 fine-to-coarse ratio and 3 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
- 4:37 PM
- Moonset
- 1:42 AM
- In sign
- ♑︎ Capricorn
Ceanothus blooms again
Read this microseason across nine climate regions →
All 72 microseasons on the year wheel →
Fremont at a glance
- Today vs. normal: Today averages 64°F (high 70°F, low 58°F), 2°F below the 66°F normal for Sep 21
- Last frost: January 7 (1991–2020 median, NOAA station 3 km away)
- Microseason: Sep 21–25
- Planting calendar: September — plant tomatoes, peppers, beans, squash; harvest tomatoes, peppers, beans, summer squash, winter squash
16-Day Forecast — Fremont
- Mon70°58°1%
- Tue73°55°1%
- Wed85°56°0%
- Thu81°62°0%
- Fri75°61°0%
- Sat79°59°0%
- Sun76°57°1%
- Mon84°58°1%
- Tue93°65°1%
- Wed95°69°3%
- Thu95°72°1%
- Fri94°77°6%
- Sat98°74°0%
- Sun90°67°0%
- Mon82°60°0%
- Tue79°60°0%
Forecast data from Open-Meteo (CC BY 4.0).
Live wind & temperature near Fremont
Interactive wind and temperature map centered on Fremont — it loads in your browser. Open the full weather map.
Right now in the garden
Peak growing season
As of September 21, the growing season is at its peak — the first frost (around December 22) is weeks away. Fall transplants go in about 10–12 weeks before the first frost, September 29 to October 13 here. This city's planting calendar for September: plant tomatoes, peppers, beans, and squash; harvest tomatoes, peppers, beans, summer squash, and winter squash.
Sun & seasons in Fremont
Fremont sits in Alameda County, where the year’s longest day runs 14h 45m of daylight and its shortest just 9h 34m — a swing of +5h 11m 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 309 miles to the SE. The nearest town Fremont tracks is Hayward, roughly 9 miles to the NW.
Air quality in Fremont
Air quality in Fremont’s county has trended cleaner since 2020; its cleanest year on record was 2023 (median AQI 48). See the full air-quality history for Fremont.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| January | lettuce, peas, spinach, radishes | lettuce, spinach, radishes, fall brassicas, carrots |
| February | — | lettuce, peas, spinach, radishes |
| March | — | lettuce, peas, spinach |
| April | — | peas |
| May | tomatoes, peppers, beans, squash | garlic |
| June | tomatoes, peppers, beans, squash | summer squash |
| July | beans, squash | tomatoes, peppers, beans, summer squash |
| August | tomatoes, peppers, beans, squash | tomatoes, peppers, beans, summer squash, winter squash |
| September | tomatoes, peppers, beans, squash | tomatoes, peppers, beans, summer squash, winter squash |
| October | beans, squash, fall brassicas, carrots | tomatoes, peppers, beans, summer squash, winter squash |
| November | garlic (overwinter) | tomatoes, peppers, beans, summer squash, winter squash |
| December | lettuce, peas, spinach, radishes, garlic (overwinter) | tomatoes, peppers, beans, summer squash, winter squash, fall brassicas, carrots |
A year in weather
Fremont peaks at about 68°F in August and bottoms near 51°F in December; February brings the heaviest rain (3.2 inches) and July the least (0.0 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 51° | 3.0″ | 6 |
| February | 53° | 3.2″ | 7 |
| March | 56° | 2.5″ | 6 |
| April | 58° | 1.2″ | 4 |
| May | 62° | 0.5″ | 2 |
| June | 65° | 0.2″ | 0 |
| July | 67° | 0.0″ | 0 |
| August | 68° | 0.0″ | 0 |
| September | 67° | 0.1″ | 0 |
| October | 63° | 0.7″ | 2 |
| November | 55° | 1.6″ | 4 |
| December | 51° | 3.0″ | 7 |
Regional context
Similar climates Newark, CA, Union City, CA, Sunol, CA
By the nearest station's NOAA NCEI 1991-2020 normals, Fremont sees 51°F Januarys and 67°F Julys, a 17°F range, plus around 15.9 inches of precipitation across 37 days.
Fremont's moisture rides winter storm tracks: February brings 3.2 inches over 6.8 wet days, while July sees only 0.0 inches across 0.0 days in the dry warm season. That cool-season-wet pattern aligns Fremont with places like Newark, CA, Union City, CA and Sunol, CA.
By January 7 the frosts ease in Fremont, opening the season for lettuce, chard, arugula, and mustard greens. In Fremont, warm-season transplants — tomatoes, peppers, basil — wait two weeks past Fremont's frost date. It shuts near December 22, when freezes return to Fremont and tender plants need cover. Sheltered Fremont yards can escape a light frost.
Similar climates: Newark, CA, Union City, CA, Sunol, CA, Milpitas, CA, Hayward, CA.
Frequently asked
- When does it freeze in Fremont?
- In Fremont, expect the last spring frost near January 7; Fremont's first autumn frost comes around December 22.
- What is the rainy season in Fremont?
- Fremont sees its heaviest rain in February (around 3.2 inches), part of roughly 16 inches a year.
- What is the warmest month in Fremont?
- On average August tops the year in Fremont at about 68°F.
- What is the coldest month in Fremont?
- The coldest stretch in Fremont falls in December, around 51°F on average.
- When can I start a vegetable garden in Fremont?
- In Fremont, sow peas and hardy greens around January 7; Fremont's tomatoes and peppers wait two weeks more.
- How many rainy days does Fremont get?
- Expect roughly 37 wet days a year in Fremont.
- What hardiness zone is Fremont?
- Because Fremont bottoms near 51°F in December, that winter low sets Fremont's USDA zone — verify by ZIP.
- What is the 10-day forecast for Fremont?
- Fremont'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 Fremont?
- See this week's day-by-day rain chances for Fremont in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Fremont?
- Current conditions for Fremont and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Fremont forecast updated?
- The Fremont forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Fremont?
- Today's sunrise and sunset times for Fremont 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 Fremont?
- The next few days in Fremont's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Fremont sits at 37.5°N; its climate zone is hot-summer Mediterranean (Köppen approximation).
ZIP codes in Fremont
- 94536
- 94537
- 94538
- 94539
- 94555
- 94560