Trenton, New Jersey Weather
Night falls a minute earlier. Day 43 of summer. Read this microseason across nine climate regions →
Trenton weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayAug 2Overcast19%—90°73°—
- MondayAug 3Light Showers49%0.24″84°74°-6°
- TuesdayAug 4Overcast38%—87°66°+3°
- WednesdayAug 5Showers37%0.20″84°70°-3°
- ThursdayAug 6Light Drizzle43%—92°72°+8°
- FridayAug 7Heavy Drizzle42%—97°75°+5°
- SaturdayAug 8Light Drizzle53%—94°74°-3°
AQI 52 (Moderate), driven by PM2.5. AQI flat over the last 6 hours (within ±3 points). PM2.5 at 9.6 µg/m³, PM10 at 12.6 µg/m³ — typical background levels with no transport signature.
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 43 now. With UV 4.1 peaking around 1 PM under partly cloudy skies, surface ozone likely climbs to AQI 17.
- Present
- AQI 43
- UV peak
- 4.1 at 1 PM
- Sky at peak
- partly cloudy
- Projected peak
- AQI 17
PM × Wind × Precip
PM2.5 at 9.6 µg/m³, PM10 at 12.6 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.76
- Wind
- breezy
- Recent rain
- 0h in last 6h
- Pattern
- background
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
- 9:42 PM
- Moonset
- 10:02 AM
- In sign
- ♓︎ Pisces
Night falls a minute earlier
Trenton at a glance
- Today vs. normal: 22°F above the seasonal normal for this latitude
- Last frost: April 17 (climatological average for this latitude)
- Microseason: Aug 1–5
- Planting window: Sow fall peas. Start kale and collard seedlings for fall.
ZIP codes: 08608, 08609, 08610, 08611, 08618, 08619, 08620, 08628 +3 more
16-Day Forecast — Trenton
- Sun90°73°19%
- Mon84°74°49%
- Tue87°66°38%
- Wed84°70°37%
- Thu92°72°43%
- Fri97°75°42%
- Sat94°74°53%
- Sun96°77°35%
- Mon96°74°27%
- Tue88°72°15%
- Wed88°65°16%
- Thu87°70°39%
- Fri96°73°45%
- Sat94°74°39%
- Sun96°75°31%
- Mon94°70°26%
Forecast data from Open-Meteo (CC BY 4.0).
Live wind & temperature near Trenton
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.
SPC Convective Outlook
Storm Prediction Center — Trenton
SPC has placed Trenton in the Marginal Risk category for severe thunderstorms today.
- TODAYMRGLMarginal Risk
- TOMORROWMRGLMarginal Risk
- DAY 3TSTMGeneral Thunderstorms
Isolated severe storms possible. Limited threat for hail or damaging wind.
Source: NOAA / NWS Storm Prediction Center categorical convective outlook. Outlooks are re-issued multiple times per day; this page reflects the most recent SPC polygons covering the city’s coordinates.
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.
Newark, the state’s largest city, lies about 47 miles to the NE. The nearest town Trenton tracks is Vincentown, roughly 20 miles to the S.
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.
Microseason · August 1–5
Night falls a minute earlier
Sunset retreats perceptibly — daylight shortening speeds up.
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
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 | Rainy days |
|---|---|---|---|
| January | 31° | 3.5″ | 13 |
| February | 33° | 3.1″ | 12 |
| March | 42° | 3.8″ | 15 |
| April | 53° | 4.0″ | 16 |
| May | 61° | 3.7″ | 17 |
| June | 71° | 3.8″ | 17 |
| July | 77° | 3.8″ | 16 |
| August | 76° | 4.2″ | 17 |
| September | 69° | 3.7″ | 13 |
| October | 58° | 3.0″ | 11 |
| November | 45° | 3.7″ | 12 |
| December | 36° | 4.2″ | 13 |
Regional context
Per NOAA NCEI 1991-2020 normals, 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 across about 173 wet days.
No season owns Trenton's rain: August reaches 4.2 inches across 17.2 days and October keeps 3.0 inches on 10.6, 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 mid-April, 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 mid-November, frost is back in Trenton — protect or harvest anything tender. Trenton's low ground holds frost later into spring than Trenton's benches, which run 3-5 days ahead.
Similar climates: The College of New Jersey, NJ, Mercerville, NJ, White Horse, NJ, Lawrenceville, NJ, Hamilton Square, NJ.
Naturalist notes
Late May brings the arrival of migrating warblers to Trenton's parks and wooded areas, their songs filling the canopy as they search for insects among newly emerged leaves.
Cherry blossoms typically reach peak bloom in mid-April, coinciding with the last expected frost dates in the region.
Frequently asked
- When does it freeze in Trenton?
- In Trenton, expect the last spring frost near mid-April; Trenton's first autumn frost comes around mid-November.
- 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 (mid-April) cues hardy greens; in Trenton, hold heat-lovers two weeks past.
- How many rainy days does Trenton get?
- Expect roughly 173 wet days a year in Trenton.
- 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.
Climate
Trenton's warm-summer humid continental climate in New Jersey pairs 31°F Januarys with 77°F Julys, 46°F apart across the seasons.
Trenton sees close to 44 inches of precipitation annually, falling across some 173 wet days.
The 46°F gap between Trenton's summer and winter, at 40.2°N, shapes Trenton's frost calendar.
ZIP codes in Trenton
- 08638
- 08611
- 08618
- 08629
- 08609
- 08608
- 08601
- 08603
- 08604
- 08605
- 08607
- 08625
- 08645
- 08646
- 08647
- 08666
- 08695