Waterbury climate
Waterbury (Connecticut, United States) has a hot-summer humid continental climate (Köppen Dfa). The average temperature over the year is 10 °C51 °F, and about 1,208 mm48 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
Waterbury climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin | Frost days |
|---|---|---|---|---|---|
| Jan | 134 | −719 | −326 | 763.0 | 28 |
| Feb | 337 | −720 | −228 | 813.2 | 26 |
| Mar | 745 | −327 | 236 | 973.8 | 24 |
| Apr | 1458 | 337 | 947 | 1054.1 | 8 |
| May | 2069 | 948 | 1559 | 953.7 | 0 |
| Jun | 2578 | 1558 | 2068 | 1174.6 | 0 |
| Jul | 2984 | 1865 | 2474 | 1014.0 | 0 |
| Aug | 2983 | 1763 | 2373 | 1094.3 | 0 |
| Sep | 2577 | 1356 | 1966 | 1064.2 | 0 |
| Oct | 1763 | 745 | 1254 | 1214.8 | 2 |
| Nov | 1151 | 134 | 643 | 893.5 | 14 |
| Dec | 440 | −326 | 033 | 1114.4 | 26 |
| Year | 2984 | −719 | 1051 | 1,20848 | 128 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total. Frost days are for the whole grid cell.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 88% | 64% | 1.8 | 9:29 |
| Feb | 87% | 62% | 2.7 | 10:33 |
| Mar | 83% | 62% | 3.7 | 11:49 |
| Apr | 78% | 62% | 4.8 | 13:17 |
| May | 78% | 64% | 5.4 | 14:30 |
| Jun | 78% | 59% | 5.9 | 15:10 |
| Jul | 74% | 55% | 6.0 | 14:54 |
| Aug | 73% | 54% | 5.3 | 13:50 |
| Sep | 74% | 50% | 4.3 | 12:25 |
| Oct | 78% | 58% | 2.9 | 11:00 |
| Nov | 81% | 59% | 2.0 | 9:47 |
| Dec | 87% | 65% | 1.5 | 9:11 |
Humid. = average relative humidity at 2 m; cloud = average cloud amount; solar = average daily solar energy reaching the ground in kWh/m² (all-sky); daylight in hours:minutes, calculated for the 15th of each month.
What the climate of Waterbury is like
The warmest month is July, with an average high of 29 °C84 °F and a low of 18 °C65 °F. The coldest is January, when highs average 1 °C34 °F and lows −7 °C19 °F. Seasons are strongly marked: the warmest month is on average 26.7 °C48 °F warmer than the coldest.
It is wet, with about 1,208 mm48 in of precipitation per year. Rain is spread fairly evenly through the year. The wettest month is October (121 mm4.8 in), the driest is January (76 mm3.0 in).
Relative humidity ranges from 73% in August to 88% in January. The clearest skies (lowest average cloud amount, 50%) are typical of September. Average wind speed near the ground ranges from 0 km/h (0 mph) in June to 3 km/h (2 mph) in February. Daylight lasts from about 9.2 hours in December to 15.2 hours in June.
A lasting snow cover is typical in December–March, when the average snow depth in the reanalysis exceeds 10 cm (deepest in January, about 16 cm).
Best time to visit Waterbury
Based on these averages, the most comfortable months for sightseeing and outdoor activities are May and July–September: average highs of 20 °C69 °F to 29 °C84 °F with 95 mm3.7 in to 109 mm4.3 in of precipitation per month.
The most challenging month is January, which is cold, with average highs of 1 °C34 °F.
Comfort score: months are ranked by how close they come to an average high of 21–28 °C (70–82 °F), lows above 5 °C (41 °F), little precipitation and moderate humidity. The best-ranked months of each place are recommended, even where none meets all of these. These are general rules of thumb applied to long-term averages.
What to pack for Waterbury
- Winter (December–February) — highs 134 to 4 °C40 °F, lows −719 to −3 °C26 °F, about 90 mm3.5 in of precipitation a month. Pack a winter coat, hat, gloves and warm, non-slip boots and shoes with good grip, as frost is common.
- Spring (March–May) — highs 745 to 20 °C69 °F, lows −327 to 9 °C48 °F, about 99 mm3.9 in of precipitation a month. Pack long sleeves, a sweater and a medium jacket, an extra layer for the cooler mornings and evenings and an umbrella or light rain jacket.
- Summer (June–August) — highs 2578 to 29 °C84 °F, lows 1558 to 18 °C65 °F, about 109 mm4.3 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses, an extra layer for the cooler mornings and evenings and an umbrella or light rain jacket.
- Autumn (September–November) — highs 1151 to 25 °C77 °F, lows 134 to 13 °C56 °F, about 105 mm4.1 in of precipitation a month. Pack long sleeves, a sweater and a medium jacket, an extra layer for the cooler mornings and evenings and an umbrella or light rain jacket.
How Waterbury compares
Compared with New Haven, about 30 km to the south, Waterbury is on average 0.4 °C0.7 °F cooler and receives a similar amount of precipitation.
Of the 222 places in the United States covered by World Climates, Waterbury is the 187th warmest by annual mean temperature and the 62nd wettest by annual precipitation. See all of them on the United States climate page.
Places in other countries with the most similar temperature and rainfall pattern: Morioka (Japan, Dfa), Hirosaki (Japan, Dfa) and Yamagata (Japan, Dfa).
Nearby places
- New Haven 30 km · 11 °C52 °F · 1,208 mm48 in
- Hartford 38 km · 10 °C51 °F · 1,201 mm47 in
- Bridgeport 44 km · 12 °C53 °F · 1,206 mm47 in
- Stamford 69 km · 11 °C53 °F · 1,236 mm49 in
- Springfield 72 km · 10 °C51 °F · 1,201 mm47 in
- Manhattan 115 km · 11 °C52 °F · 1,236 mm49 in
- Paterson 118 km · 11 °C52 °F · 1,240 mm49 in
- New York City 123 km · 12 °C54 °F · 1,312 mm52 in
Frequently asked questions
What is the warmest month in Waterbury?
July is the warmest month in Waterbury, with an average high of 29 °C (84 °F) and an average low of 18 °C (65 °F).
What is the coldest month in Waterbury?
January is the coldest month, with an average high of 1 °C (34 °F) and an average low of -7 °C (19 °F).
When does it rain the most in Waterbury?
October is the wettest month with about 121 mm (4.8 in) of precipitation; January is the driest with about 76 mm (3.0 in).
What is the best time to visit Waterbury?
Judging by long-term averages, the most comfortable months are May and July–September.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.
The grid cell’s average elevation is 149 m, while Waterbury lies at about 82 m. Temperatures on this page were therefore adjusted by +0.4 °C0.8 °F using the standard lapse rate of 6.5 °C per 1,000 m.