Weather in New Haven, Connecticut
Roses open along the stoops. Day 59 of spring. Read this microseason across nine climate regions →
- TodayMay 16Overcast—73°47°
- SundayMay 17Overcast—87°59°
- MondayMay 18Overcast16%73°57°
- TuesdayMay 19Light Drizzle11%78°57°
- WednesdayMay 20Showers66%84°58°
- ThursdayMay 21Overcast38%68°53°
- FridayMay 22Light Drizzle16%59°49°
- PM 2.5
- 10.7 μg/m³
- PM 10
- 15.0 μg/m³
- NO₂
- 5.1 μg/m³
- Ozone
- 106.0 μg/m³
- UV Index
- 0.0 Low
When the dew is on the grass, rain will never come to pass.
- Moonrise
- 9:34 AM
- Moonset
- 12:32 AM
- In sign
- ♉︎ Taurus
Roses open along the stoops
New Haven at a glance
- Today vs. normal: 7°F below the seasonal normal for this latitude
- Last frost: April 24 (climatological average for this latitude)
- Microseason: 28 of 72, May 16–20
- Planting window: Direct sow okra, melons, and southern peas. Thin carrot rows.
Right now in the garden
Warm-season window is open
As of May 17, the last spring frost has passed for most years. Transplant tomatoes, peppers, eggplants, basil, and cucurbits (cucumbers, squash, melons) now. Direct-sow beans and corn into warm soil.
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
July brings New Haven's warmest temperatures at around 74°F mean, while January delivers the coldest at roughly 31°F. April sees peak rainfall with 4.2 inches, contrasting with January's drier 2.7 inches.
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 31° | 2.7″ | 5 |
| February | 32° | 2.8″ | 6 |
| March | 39° | 3.7″ | 6 |
| April | 49° | 4.2″ | 7 |
| May | 59° | 3.5″ | 7 |
| June | 68° | 3.5″ | 7 |
| July | 74° | 3.4″ | 6 |
| August | 73° | 3.5″ | 6 |
| September | 66° | 4.0″ | 5 |
| October | 55° | 3.8″ | 7 |
| November | 45° | 3.1″ | 6 |
| December | 36° | 3.5″ | 7 |
Regional context
Located in a warm-summer humid continental climate region, New Haven shares temperature ranges, seasonal patterns, and growing conditions with other nearby cities in this climate zone.
Similar climates: Hartford, CT, Bridgeport, CT, Waterbury, CT, Danbury, CT, Norwich, CT.
Naturalist notes
Late May brings the arrival of ruby-throated hummingbirds to New Haven gardens and parks.
By mid-June, common milkweed begins its distinctive pink-purple bloom across Connecticut meadows.
Frequently asked
- When does it freeze in New Haven?
- Spring's final frost usually occurs around mid-April in New Haven, while the first fall frost typically arrives around mid-November.
- What is the rainy season in New Haven?
- April stands as the wettest month, delivering about 4.2 inches of rain on average, while the city's annual total reaches roughly 42 inches.
- What is the warmest month in New Haven?
- July typically brings the warmest weather, with temperatures averaging about 74°F.
- What is the coldest month in New Haven?
- January usually delivers the coldest conditions, averaging about 31°F.
- When can I start a vegetable garden in New Haven?
- Cool-season crops like peas and lettuce can go into the ground around the last spring frost in mid-April, while warm-season varieties such as tomatoes and peppers should wait 1–2 weeks after that date.
- How many rainy days does New Haven get?
- New Haven typically experiences about 74 rainy days each year.
- What hardiness zone is New Haven?
- New Haven's USDA hardiness zone depends on its lowest average winter temperature; the USDA's online lookup tool can provide the current zone designation using the city ZIP.
Climate
New Haven, Connecticut experiences a warm-summer humid continental climate. January temperatures hover near 31°F while July averages reach 74°F, creating a 43°F seasonal swing.
Annual precipitation totals about 42 inches across roughly 74 rainy days throughout the year.
Weather patterns here depend on the city's latitude at 41.3°N, its proximity to large water bodies, and local elevation. These factors determine growing seasons, frost timing, and daily weather conditions.