Danbury, Connecticut climate: Normal weather by month, frost dates and records
Danbury's normal year runs from 18°F January nights to 82°F July afternoons, with 48.0 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 9.8°C, January lows of −8°C, July highs of 28°C, 1,220 mm of precipitation a year.
- NOAA stationDanbury Municipal Airport
- Station IDUSW00054734
- Location41.37°N 73.48°W
- Elevation457 ft (139 m)
- From the center2 miles
- Population88,692
On October 22, the normal high in Danbury is 60°F and the normal low 39°F, and the chance of measurable rain or snow is 39%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Danbury.
- Jan 36° 18°
- Feb 39° 20°
- Mar 47° 27°
- Apr 59° 37°
- May 69° 46°
- Jun 78° 56°
- Jul 82° 62°
- Aug 80° 60°
- Sep 74° 52°
- Oct 62° 41°
- Nov 51° 31°
- Dec 41° 24°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Danbury each month?
July is the warmest month, with normal highs of 82°F; January the coldest, with normal lows of 18°F. The most precipitation falls in September (4.81 in), the least in February (2.69 in).
Each month has its own page with the day-by-day normals, the month's records and its recent years:
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 36°F | 18°F | 27.0°F | 3.06 | 11 | <1 | 28 | 9 h 30 min |
| February | 39°F | 20°F | 29.2°F | 2.69 | 10 | <1 | 26 | 10 h 40 min |
| March | 47°F | 27°F | 36.9°F | 3.89 | 11 | <1 | 22 | 11 h 50 min |
| April | 59°F | 37°F | 47.7°F | 3.74 | 12 | <1 | 9 | 13 h 20 min |
| May | 69°F | 46°F | 57.8°F | 3.78 | 14 | <1 | 1 | 14 h 30 min |
| June | 78°F | 56°F | 66.9°F | 4.48 | 13 | 1 | <1 | 15 h 10 min |
| July | 82°F | 62°F | 72.0°F | 4.46 | 13 | 4 | <1 | 14 h 50 min |
| August | 80°F | 60°F | 70.2°F | 4.62 | 14 | 2 | <1 | 13 h 50 min |
| September | 74°F | 52°F | 62.9°F | 4.81 | 14 | <1 | <1 | 12 h 30 min |
| October | 62°F | 41°F | 51.5°F | 4.48 | 13 | <1 | 5 | 11 h 10 min |
| November | 51°F | 31°F | 41.2°F | 3.78 | 11 | <1 | 17 | 9 h 50 min |
| December | 41°F | 24°F | 32.4°F | 4.24 | 12 | <1 | 25 | 9 h 10 min |
| Year (annual) | 60°F | 40°F | 49.6°F | 48.03 | 147 | 8 | 134 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 2°C | −8°C | −2.8°C | 78 mm |
| February | 4°C | −7°C | −1.6°C | 68 mm |
| March | 8°C | −3°C | 2.7°C | 99 mm |
| April | 15°C | 3°C | 8.7°C | 95 mm |
| May | 21°C | 8°C | 14.3°C | 96 mm |
| June | 25°C | 13°C | 19.4°C | 114 mm |
| July | 28°C | 16°C | 22.2°C | 113 mm |
| August | 27°C | 16°C | 21.2°C | 117 mm |
| September | 23°C | 11°C | 17.2°C | 122 mm |
| October | 17°C | 5°C | 10.8°C | 114 mm |
| November | 11°C | 0°C | 5.1°C | 96 mm |
| December | 5°C | −5°C | 0.2°C | 108 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. Danbury's own co-op station Danbury station does: 49 inches of snow in a normal year (see the other stations below).
Source: NOAA NCEI 1991-2020 monthly normals, station USW00054734; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Danbury?
Normal highs sit between 65°F and 85°F in May, June, July, August and September. Of those, July has the fewest days with rain (13).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00054734.
When is the last frost in Danbury?
In Danbury, the last spring frost (32°F) comes after May 1 in half of years and after May 16 in one year in ten; the first autumn frost comes before October 14 in half of years and before October 1 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- May 11 year in 10 after May 16; 9 in 10 after April 18
- First autumn frost, half of years before
- October 141 year in 10 before October 1; 9 in 10 before October 29
NOAA puts the median frost-free season at 166 days, and the season without a hard freeze (28°F) at 191 days.
A hard freeze (28°F) comes after April 18 in half of springs and before October 27 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Danbury in zone 6b across its 2 ZIP code areas (6b in 06811, the largest). By the map's own method, the average of each year's coldest night over 1991-2020, Danbury's NOAA station is in zone 6b: the coldest night of a typical year reaches −4°F (20 complete years).
Frost dates for every NOAA station in Connecticut · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00054734; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
What hardiness zone is each Danbury ZIP code in?
The USDA's 2023 map gives each ZIP code area one zone. Danbury's 2 ZIP code areas are all in zone 6b. Each ZIP's frost dates are in the frost tool.
Source: USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; ZIP areas in the place: Census Bureau 2020 ZCTA-to-place relationship file. A ZIP area counts when at least a tenth of its land (and 0.5 km²) lies in the place.
How hot and how cold does it get in Danbury?
In a normal year in Danbury, 8 days a year reach 90°F, 134 nights fall to 32°F or colder and 147 days bring measurable precipitation.
- Days at 90°F or more
- 8a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 134a normal year
- Days that stay below freezing
- 28high of 32°F or less
- Days with 0.01 inch of precipitation
- 147a normal year
The highest temperature in this station's record (since 1998) is 100°F, on July 6, 2010; the lowest is −14°F, on January 7, 2018.
The wettest calendar year on that record is 2011, with 69.71 in.
Source: NOAA NCEI 1991-2020 annual normals, station USW00054734; records: ACIS (NOAA Regional Climate Centers), station USW00054734. Records use complete months only; a month missing more than three days is left out.
How sunny is Danbury?
Over a year 72% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Danbury, 3.9 kWh per square metre a day. July is the sunniest month (79%) and December the cloudiest (65%). Among the 459 U.S. places of 50,000 or more, that ranks tied 385th (with 30 others) in sunshine.
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 68% | 1.8 |
| February | 70% | 2.7 |
| March | 68% | 3.7 |
| April | 69% | 4.8 |
| May | 69% | 5.4 |
| June | 74% | 5.9 |
| July | 79% | 6.0 |
| August | 78% | 5.3 |
| September | 77% | 4.3 |
| October | 70% | 2.9 |
| November | 70% | 2.0 |
| December | 65% | 1.5 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Danbury need?
A normal year in Danbury brings 6,158 heating degree days, 15% more than the median U.S. place (5,373), and 594 cooling degree days, 35% fewer than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,690 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,178 | 0 |
| February | 1,002 | 0 |
| March | 870 | 0 |
| April | 523 | 3 |
| May | 246 | 22 |
| June | 51 | 108 |
| July | 6 | 223 |
| August | 13 | 175 |
| September | 120 | 58 |
| October | 423 | 6 |
| November | 714 | 0 |
| December | 1,012 | 0 |
| Year (annual) | 6,158 | 594 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00054734. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Danbury been warmer than normal lately?
2025 averaged 52.0°F, 2.4°F above the 1991-2020 normal of 49.6°F. 5 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 53.1°F | +3.5°F | 39.95 |
| 2022 | 52.9°F | +3.3°F | – |
| 2023 | 53.5°F | +3.9°F | – |
| 2024 | 53.5°F | +3.9°F | 49.72 |
| 2025 | 52.0°F | +2.4°F | – |
Source: observed years: ACIS, station USW00054734. A year counts only with all twelve months complete.
How does Danbury's climate compare?
Danbury is warmer than 2 of the other 12 places with their own NOAA record in Connecticut, and wetter than 7. Across the 7,247 U.S. stations with normals, its annual mean of 49.6°F is warmer than 38%.
In the Köppen classification computed from these normals, Danbury is Dfa: continental, no dry season, hot summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Danbury share this climate record?
20 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Bethel, CT21,490 people · 4 mi E
- Mahopac, NY9,171 people · 13 mi W
- Heritage Hills, NY3,967 people · 11 mi W
- Putnam Lake, NY3,673 people · 8 mi NW
- Brewster, NY2,504 people · 7 mi W
- Brewster Hill, NY2,211 people · 7 mi NW
- Pawling, NY2,070 people · 15 mi NW
- Georgetown, CT1,751 people · 9 mi S
- Shenorock, NY1,643 people · 14 mi W
- Golden's Bridge, NY1,549 people · 11 mi SW
- Brewster Heights, NY1,356 people · 8 mi W
- Wingdale, NY1,309 people · 19 mi N
- Lakes East, CT1,295 people · 3 mi S
- Lincolndale, NY1,235 people · 13 mi W
- Route 7 Gateway, CT1,032 people · 4 mi S
- Peach Lake, NY988 people · 5 mi W
- Redding Center, CT217 people · 7 mi SE
- Dodgingtown, CT199 people · 7 mi E
- Topstone, CT94 people · 6 mi S
- Branchville, CT91 people · 7 mi S
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
What do Danbury's other NOAA stations record?
One more NOAA station keeps 1991-2020 normals in or near Danbury. This page uses Danbury Municipal Airport; the other differs by site and elevation:
| Station | From the center | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Danbury station USC00061762 | 3 mi E | 405 ft | 51.3°F | 21°F | 85°F | 53.0 | 49 | April 20 |
Source: NOAA NCEI 1991-2020 normals for each station. Last frost: the median last spring date of 32°F.
Questions about Danbury's climate
What is the coldest month in Danbury?
January, with a normal high of 36°F and a normal low of 18°F. The warmest is July (82°F by day, 62°F at night).
Does it snow in Danbury?
Yes. NOAA publishes no 1991-2020 snowfall normal for Danbury's NOAA station; Danbury's own co-op station Danbury station records 49 inches of snow in a normal year.
What is the rainiest month in Danbury?
September, with 4.81 in of precipitation in a normal year; the driest is February with 2.69 in.
What plant hardiness zone is Danbury in?
The USDA's 2023 map puts Danbury in zone 6b across its 2 ZIP code areas (6b in 06811, the largest). By the same method at Danbury's NOAA station, the coldest night of a typical year reaches −4°F (20 years, 1991-2020): zone 6b.
How late can frost come in Danbury?
In half of years the last 32°F night comes after May 1; in one year in ten it comes after May 16. Waiting until May 16 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Danbury in OctoberThis month day by day, its records and recent years
- Connecticut climateThe statewide normals and every place in the state
- Carmel, NY11 miles from this station, 48.0°F a year
- Stormville, NY17 miles from this station, 50.4°F a year
- Stamford, CT17 miles from this station, 52.6°F a year
- Yorktown Heights, NY18 miles from this station, 49.4°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made