Trenton, New Jersey Weather
Apples hang heavy on the branch. Day 93 of summer. Read this microseason across nine climate regions →
Trenton weather forecast — hour by hour, 7-day outlook, NOAA radar
Conditions updated 10:25 AM EDT · Open-Meteo
- TodaySep 21Overcast later65%0.07″69°62°—
- TuesdaySep 22Drizzle25%0.03″63°56°-6°
- WednesdaySep 23Overcast——64°53°+1°
- ThursdaySep 24Overcast——68°52°+4°
- FridaySep 25Partly Cloudy44%—72°49°+4°
- SaturdaySep 26Mostly Clear39%—75°52°+3°
- SundaySep 27Clear23%—77°55°+2°
Air quality now AQI 37 · Good
AQI 37 (Good), driven by Ozone. AQI flat over the last 6 hours (within ±3 points).
OK No precautions needed for the general population; unusually sensitive individuals may consider limiting prolonged outdoor exertion.
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
- 4:31 PM
- Moonset
- 1:16 AM
- In sign
- ♑︎ Capricorn
Apples hang heavy on the branch
Read this microseason across nine climate regions →
All 72 microseasons on the year wheel →
Trenton at a glance
- Today vs. normal: Today averages 66°F (high 69°F, low 62°F), about the 67°F normal for Sep 21
- Last frost: April 17 (1991–2020 median, NOAA station 6 km away)
- Microseason: Sep 21–25
- Planting calendar: September — plant garlic (overwinter); harvest tomatoes, peppers, beans, summer squash, winter squash
16-Day Forecast — Trenton
- Mon69°62°65%
- Tue63°56°25%
- Wed64°53°9%
- Thu68°52°7%
- Fri72°49°44%
- Sat75°52°39%
- Sun77°55°23%
- Mon78°58°8%
- Tue75°62°9%
- Wed79°60°16%
- Thu80°63°16%
- Fri76°56°15%
- Sat75°56°16%
- Sun75°60°23%
- Mon72°56°19%
- Tue62°47°20%
Forecast data from Open-Meteo (CC BY 4.0).
Live wind & temperature near Trenton
Interactive wind and temperature map centered on Trenton — it loads in your browser. Open the full weather map.
Right now in the garden
Fall planting + final harvests
As of September 21, the season's first frost (typically October 28) is approaching. Pick what frost-tender plants still carry before the next cold front. This city's planting calendar for September: plant garlic (overwinter); harvest tomatoes, peppers, beans, summer squash, and winter squash.
Sun & seasons in Trenton
Trenton sits in Mercer County, where the year’s longest day runs 15h 2m of daylight and its shortest just 9h 18m — a swing of +5h 44m between the June and December solstices. Clocks spring forward on Sunday, March 8, 2026 and fall back on Sunday, November 1, 2026.
Trenton is the state’s largest city. The nearest town Trenton tracks is Vincentown, roughly 20 miles to the S.
Air quality in Trenton
Air quality in Trenton’s county has held roughly steady since 2020; its cleanest year on record was 2020 (median AQI 42). See the full air-quality history for Trenton.
Planting calendar
| Month | Plant | Harvest |
|---|---|---|
| March | lettuce, peas, spinach, radishes | — |
| April | lettuce, peas, spinach, radishes | radishes |
| May | tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes |
| June | tomatoes, peppers, beans, squash | lettuce, peas, spinach, radishes |
| July | tomatoes, peppers, beans, squash | beans, summer squash, garlic |
| August | beans, squash, fall brassicas, carrots | tomatoes, peppers, beans, summer squash, winter squash |
| September | garlic (overwinter) | tomatoes, peppers, beans, summer squash, winter squash |
| October | garlic (overwinter) | tomatoes, peppers, beans, summer squash, winter squash, fall brassicas, carrots |
| November | — | fall brassicas, carrots |
A year in weather
Trenton's warmest month is July (~77°F mean) and its coldest is January (~31°F). Rainfall peaks in August (4.2 inches) and bottoms out in October (3.0 inches).
| Month | Mean temp | Precip |
|---|---|---|
| January | 31° | 3.5″ |
| February | 33° | 3.1″ |
| March | 42° | 3.8″ |
| April | 53° | 4.0″ |
| May | 61° | 3.7″ |
| June | 71° | 3.8″ |
| July | 77° | 3.8″ |
| August | 76° | 4.2″ |
| September | 69° | 3.7″ |
| October | 58° | 3.0″ |
| November | 45° | 3.7″ |
| December | 36° | 4.2″ |
Regional context
Similar climates The College of New Jersey, NJ, Mercerville, NJ, White Horse, NJ
Per modelled 1991-2020 normals (EC_Earth3P_HR model via Open-Meteo), Trenton runs from a 31°F January mean to 77°F in July, a 46°F seasonal spread, with near 44.4 inches of precipitation.
No season owns Trenton's rain: August reaches 4.2 inches and October keeps 3.0 inches, an even spread through Trenton's year. It is a balanced pattern Trenton shares with places like The College of New Jersey, NJ, Mercerville, NJ and White Horse, NJ.
Around April 17, Trenton sheds its freezing nights — peas, lettuce, spinach, and radishes go into Trenton's beds. Heat-demanding starts go out a fortnight on in Trenton, after the soil warms and cold snaps clear. By October 28, frost is back in Trenton — protect or harvest anything tender. That date is a median: Trenton freezes sooner in half of years.
Similar climates: The College of New Jersey, NJ, Mercerville, NJ, White Horse, NJ, Lawrenceville, NJ, Hamilton Square, NJ.
Frequently asked
- When does it freeze in Trenton?
- In Trenton, expect the last spring frost near April 17; Trenton's first autumn frost comes around October 28.
- What is the rainy season in Trenton?
- Rainfall in Trenton peaks in August near 4.2 inches, out of about 44 inches annually.
- What is the warmest month in Trenton?
- The warmest stretch in Trenton comes in July, around 77°F on average.
- What is the coldest month in Trenton?
- On average January is the chilliest month in Trenton, about 31°F.
- When can I start a vegetable garden in Trenton?
- Trenton's last frost (April 17) cues hardy greens; in Trenton, hold heat-lovers two weeks past.
- What hardiness zone is Trenton?
- Trenton sits in the USDA zone set by January lows near 31°F; the USDA ZIP tool gives the band.
- What is the 10-day forecast for Trenton?
- Trenton'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 Trenton?
- See this week's day-by-day rain chances for Trenton in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in Trenton?
- Current conditions for Trenton and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the Trenton forecast updated?
- The Trenton forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in Trenton?
- Today's sunrise and sunset times for Trenton 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 Trenton?
- The next few days in Trenton's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
Trenton sits at 40.2°N; its climate zone is warm-summer humid continental (Köppen approximation).
ZIP codes in Trenton
- 08601
- 08603
- 08604
- 08605
- 08607
- 08608
- 08609
- 08610
- 08611
- 08618
- 08619
- 08620
- 08625
- 08628
- 08629
- 08638
- 08645
- 08646
- 08647
- 08666
- 08690
- 08695