Danbury, Connecticut Weather
Fireflies rise from the lawn. Day 77 of spring. Read this microseason across nine climate regions →
Danbury weather forecast — hour by hour, 7-day outlook, NOAA radar
- TodayJun 4Overcast——85°55°—
- FridayJun 5Overcast——90°60°+5°
- SaturdayJun 6Showers41%0.09″89°64°-1°
- SundayJun 7Light Showers59%0.09″83°62°-6°
- MondayJun 8Overcast16%—78°54°-5°
- TuesdayJun 9Overcast——82°55°+4°
- WednesdayJun 10Overcast10%—85°59°+3°
PM2.5 at 9.5 µg/m³ (AQI 52) with a 0.95 fine-to-coarse ratio and 1 mph wind — combustion smoke trapped in calm air, not road dust. AQI down 8 over the last 6 hours (steady decline since this morning).
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 9.5 µg/m³ (AQI 52) with a 0.95 fine-to-coarse ratio and 1 mph wind — combustion smoke trapped in calm air, not road dust.
- PM2.5/PM10
- 0.95
- Wind
- calm
- Recent rain
- 0h in last 6h
- Pattern
- stagnant smoke
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
- 3:26 AM
- Moonset
- 12:48 PM
- In sign
- ♑︎ Capricorn
Fireflies rise from the lawn
Danbury at a glance
- Today vs. normal: 14°F below the seasonal normal for this latitude
- Last frost: April 24 (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.
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 Danbury's peak warmth with average temperatures around 72°F, while January delivers the year's coldest conditions at roughly 27°F. September typically sees the heaviest rainfall at 4.8 inches, compared to February's lighter 2.7 inches.
| Month | Mean temp | Precip | Rainy days |
|---|---|---|---|
| January | 27° | 3.1″ | 6 |
| February | 29° | 2.7″ | 5 |
| March | 37° | 3.9″ | 7 |
| April | 48° | 3.7″ | 7 |
| May | 58° | 3.8″ | 8 |
| June | 67° | 4.5″ | 7 |
| July | 72° | 4.5″ | 7 |
| August | 70° | 4.6″ | 7 |
| September | 63° | 4.8″ | 6 |
| October | 52° | 4.5″ | 6 |
| November | 41° | 3.8″ | 6 |
| December | 32° | 4.2″ | 7 |
Regional context
Danbury falls within the warm-summer humid continental climate region, sharing temperature ranges, seasonal patterns, and growing conditions with other cities in this climate zone.
Similar climates: Hartford, CT, Bridgeport, CT, New Haven, CT, Waterbury, CT, Norwich, CT.
Naturalist notes
Late May brings the peak migration of warblers through Danbury's woodlands, with yellow warblers and American redstarts arriving to establish breeding territories.
Apple trees complete their blooming cycle by early May, as petals give way to small green fruits that will mature through the summer months.
Frequently asked
- When does it freeze in Danbury?
- Danbury typically experiences its last spring frost around mid-April, while the first fall frost usually arrives around mid-November.
- What is the rainy season in Danbury?
- September ranks as the wettest month, averaging about 4.8 inches of rainfall, while the city receives roughly 48 inches annually.
- What is the warmest month in Danbury?
- July typically brings the warmest temperatures, averaging about 72°F.
- What is the coldest month in Danbury?
- January usually delivers the coldest temperatures, averaging about 27°F.
- When can I start a vegetable garden in Danbury?
- Cool-season crops like peas and lettuce can be planted around the last spring frost in mid-April, while warm-season crops such as tomatoes and peppers should wait 1–2 weeks after.
- How many rainy days does Danbury get?
- Danbury experiences about 78 rainy days per year on average.
- What hardiness zone is Danbury?
- Danbury'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 code.
Climate
Danbury, Connecticut experiences a warm-summer humid continental climate. Winter temperatures in January typically hover near 27°F, while July averages reach 72°F, creating a 45°F seasonal swing.
Annual precipitation totals approximately 48 inches, distributed across roughly 78 rainy days throughout the year.
Geography shapes Danbury's weather patterns through its latitude of 41.4°N, proximity to large water bodies, and local elevation. These factors determine growing seasons, frost timing, and daily weather variations.