New Haven, Connecticut Weather
Apples hang heavy on the branch. Day 93 of summer. Read this microseason across nine climate regions →
New Haven weather forecast — hour by hour, 7-day outlook, NOAA radar
Conditions updated 1:30 AM EDT · Open-Meteo
- TodaySep 21Overcast14%0.02″68°56°—
- TuesdaySep 22Overcast11%—65°53°-3°
- WednesdaySep 23Overcast——65°52°0°
- ThursdaySep 24Overcast——67°47°+2°
- FridaySep 25Light Drizzle44%0.05″57°51°-10°
- SaturdaySep 26Drizzle41%0.11″57°53°0°
- SundaySep 27Light Drizzle31%—57°55°0°
Air quality now AQI 39 · Good
AQI 39 (Good), driven by PM2.5. AQI flat over the last 6 hours (within ±3 points). PM2.5 at 7.5 µg/m³, PM10 at 9.6 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
PM × Wind × Precip
PM2.5 at 7.5 µg/m³, PM10 at 9.6 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.78
- Wind
- breezy
- Recent rain
- 1h 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).
September dries up ditches or breaks down bridges.
- Moonrise
- 4:27 PM
- Moonset
- 1:05 AM
- In sign
- ♑︎ Capricorn
Apples hang heavy on the branch
Read this microseason across nine climate regions →
All 72 microseasons on the year wheel →
New Haven at a glance
- Today vs. normal: Today averages 62°F (high 68°F, low 56°F), 4°F below the 66°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
15-Day Forecast — New Haven
- Mon68°56°14%
- Tue65°53°11%
- Wed65°52°4%
- Thu67°47°9%
- Fri57°51°44%
- Sat57°53°41%
- Sun57°55°31%
- Mon60°57°14%
- Tue61°57°11%
- Wed60°57°19%
- Thu66°58°14%
- Fri66°54°6%
- Sat72°56°10%
- Sun75°62°30%
- Mon64°55°30%
Forecast data from Open-Meteo (CC BY 4.0).
Live wind & temperature near New Haven
Interactive wind and temperature map centered on New Haven — 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 27) 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 New Haven
New Haven sits in South Central Connecticut County, where the year’s longest day runs 15h 10m of daylight and its shortest just 9h 11m — a swing of +5h 58m between the June and December solstices. Clocks spring forward on Sunday, March 8, 2026 and fall back on Sunday, November 1, 2026.
Hartford, the state’s largest city, lies about 34 miles to the NNE. The nearest town New Haven tracks is Bridgeport, roughly 16 miles to the WSW.
Air quality in New Haven
Air quality in New Haven’s county has held roughly steady since 2020; its cleanest year on record was 2024 (median AQI 41). See the full air-quality history for New Haven.
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 | lettuce, peas, beans, summer squash, garlic |
| August | beans, squash, fall brassicas, carrots | tomatoes, peppers, beans, summer 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
New Haven peaks at about 75°F in July and bottoms near 30°F in January; December brings the heaviest rain (4.7 inches) and February the least (3.3 inches).
| Month | Mean temp | Precip |
|---|---|---|
| January | 30° | 4.0″ |
| February | 32° | 3.3″ |
| March | 39° | 3.9″ |
| April | 50° | 4.3″ |
| May | 58° | 4.0″ |
| June | 68° | 3.9″ |
| July | 75° | 3.6″ |
| August | 74° | 4.0″ |
| September | 68° | 3.7″ |
| October | 58° | 3.7″ |
| November | 45° | 4.6″ |
| December | 35° | 4.7″ |
Regional context
Similar climates West Haven, CT, Branford Center, CT, Woodmont, CT
Per modelled 1991-2020 normals (EC_Earth3P_HR model via Open-Meteo), New Haven runs from a 30°F January mean to 75°F in July, a 45°F seasonal spread, with near 47.7 inches of precipitation.
No season owns New Haven's rain: December reaches 4.7 inches and February keeps 3.3 inches, an even spread through New Haven's year. That even rhythm groups New Haven with places like West Haven, CT, Branford Center, CT and Woodmont, CT.
Around April 17, New Haven sheds its freezing nights — peas, lettuce, spinach, and radishes go into New Haven's beds. New Haven's heat-lovers — tomatoes, peppers, squash — hold off until New Haven's frost risk clears, 10-14 days on. Frost returns to New Haven near October 27, ending the tender-crop season. That date is a median: New Haven freezes sooner in half of years.
Similar climates: West Haven, CT, Branford Center, CT, Woodmont, CT, Quinnipiac University, CT, Ansonia, CT.
Frequently asked
- When does it freeze in New Haven?
- In New Haven, expect the last spring frost near April 17; New Haven's first autumn frost comes around October 27.
- What is the rainy season in New Haven?
- December is the wettest month in New Haven, about 4.7 inches on average; the year totals roughly 48 inches.
- What is the warmest month in New Haven?
- On average July tops the year in New Haven at about 75°F.
- What is the coldest month in New Haven?
- The coldest stretch in New Haven falls in January, around 30°F on average.
- When can I start a vegetable garden in New Haven?
- In New Haven, sow peas and hardy greens around April 17; New Haven's tomatoes and peppers wait two weeks more.
- What hardiness zone is New Haven?
- With January around 30°F, New Haven's zone reflects that minimum — the USDA ZIP map confirms New Haven's band.
- What is the 10-day forecast for New Haven?
- New Haven'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 New Haven?
- See this week's day-by-day rain chances for New Haven in the daily forecast above, and the next 24 hours in the hourly chart.
- What is the weather like right now in New Haven?
- Current conditions for New Haven and the next 24 hours — temperature, precipitation chance, and wind by the hour — are in the hourly forecast chart above.
- How often is the New Haven forecast updated?
- The New Haven forecast on this page is built from Open-Meteo weather-model data and refreshes regularly through the day.
- When are sunrise and sunset in New Haven?
- Today's sunrise and sunset times for New Haven 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 New Haven?
- The next few days in New Haven's forecast are the most reliable; accuracy declines beyond about a week as weather-model uncertainty grows.
New Haven sits at 41.3°N; its climate zone is warm-summer humid continental (Köppen approximation).
ZIP codes in New Haven
- 06501
- 06502
- 06503
- 06505
- 06506
- 06507
- 06508
- 06509
- 06510
- 06511
- 06512
- 06513
- 06515
- 06519
- 06520
- 06521
- 06530
- 06531
- 06532
- 06533
- 06534
- 06535
- 06536
- 06540