New Britain, Connecticut Weather
Fireflies rise from the lawn. Day 77 of spring. Read this microseason across nine climate regions →
New Britain weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Clear——88°53°—
- FridayJun 5Overcast——90°63°+2°
- SaturdayJun 6Light Showers39%0.01″91°65°+1°
- SundayJun 7Heavy Drizzle47%—83°60°-8°
- MondayJun 8Drizzle—0.04″79°53°-4°
- TuesdayJun 9Overcast——86°53°+7°
- WednesdayJun 10Partly Cloudy——90°56°+4°
Ozone at AQI 83 — peak already passed at 1 PM under clear skies. AQI up 20 in the last 6 hours — air quality is degrading. Levels should ease through evening.
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 83 — peak already passed at 1 PM under clear skies. Levels should ease through evening.
- Present
- AQI 83
- UV peak
- 3.4 at earlier today
- Sky at peak
- clear
- Projected peak
- AQI 83
PM × Wind × Precip
PM2.5 at 5.4 µg/m³, PM10 at 6.3 µg/m³ — typical background levels with no transport signature.
- PM2.5/PM10
- 0.86
- Wind
- light
- 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).
A summer fog for fair, a winter fog for rain.
- Moonrise
- 3:24 AM
- Moonset
- 12:45 PM
- In sign
- ♒︎ Aquarius
Fireflies rise from the lawn
New Britain at a glance
- Today vs. normal: 14°F above the seasonal normal for this latitude
- Last frost: April 26 (climatological average for this latitude)
- Microseason: Jun 1–5
- Planting window: Harvest spring lettuce before it bolts. Sow heat-tolerant greens.
Right now in the garden
Peak growing season
As of June 4, 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 — New Britain
SPC has placed New Britain in the Marginal Risk category for severe thunderstorms day after tomorrow.
- TODAYNONENo severe risk
- TOMORROWNONENo severe risk
- DAY 3MRGLMarginal Risk
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.
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
New Britain's warmest month is July (~75°F mean) and its coldest is January (~29°F). Rainfall peaks in October (4.2 inches) and bottoms out in February (2.6 inches).
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 29° | 2.9″ | 6 |
| February | 31° | 2.6″ | 6 |
| March | 39° | 3.5″ | 7 |
| April | 50° | 3.8″ | 6 |
| May | 61° | 3.4″ | 7 |
| June | 70° | 3.9″ | 6 |
| July | 75° | 3.9″ | 7 |
| August | 74° | 3.5″ | 6 |
| September | 66° | 4.0″ | 5 |
| October | 54° | 4.2″ | 6 |
| November | 43° | 3.4″ | 6 |
| December | 34° | 3.8″ | 8 |
Regional context
New Britain sits within a warm-summer humid continental climate region — a cohort that shares similar temperature ranges, seasonal patterns, and growing conditions across nearby cities.
Similar climates: Hartford, CT, Bridgeport, CT, New Haven, CT, Waterbury, CT, Danbury, CT.
Frequently asked
- When does it freeze in New Britain?
- New Britain's last spring frost typically falls around mid-April, and the first fall frost arrives around mid-November.
- What is the rainy season in New Britain?
- October is the wettest month with about 4.2 inches of rain on average; the city receives roughly 43 inches annually.
- What is the warmest month in New Britain?
- July is typically warmest, averaging about 75°F.
- What is the coldest month in New Britain?
- January is typically coldest, averaging about 29°F.
- When can I start a vegetable garden in New Britain?
- Cool-season crops (peas, lettuce) can be sown around the last spring frost (mid-April); warm-season crops (tomatoes, peppers) wait until 1–2 weeks after.
- How many rainy days does New Britain get?
- New Britain averages about 76 rainy days per year.
- What hardiness zone is New Britain?
- New Britain's USDA hardiness zone is determined by its lowest average winter temperature; check the USDA's online lookup with the city ZIP for the current zone designation.
Climate
New Britain, Connecticut sits in a warm-summer humid continental climate zone. January means hover near 29°F while July averages 75°F — a 47°F seasonal swing.
Across the year, New Britain receives about 43 inches of precipitation spread over roughly 76 rainy days.
The rhythm of the year is set by latitude (41.7°N), proximity to large water bodies, and elevation — all of which shape what grows here, when frost is likely, and what the weather story looks like day to day.