Climate - New Haven (Connecticut)

The climate of New Haven is continental, with cold winters and hot summers.
The city is the home of Yale University and is located on the coast of the Long Island Sound, at the mouth of the Quinnipiac River, and 100 kilometres (60 miles) northeast of New York. In fact, the climate is similar to that of New York, though it is a bit colder.
The city lies on the coast, but it's also on the edge of a continent that cools down in winter and heats up in summer, and where different air masses collide: the cold ones coming from Canada and the warm ones coming from the Gulf of Mexico. The result is an unstable climate, with waves of bad weather alternating with clear and sunny days. The wind blows frequently as well.
The average temperature of the coldest month (January) is of -0.8 °C (30.5 °F), that of the warmest month (July) is of 23.3 °C (73.9 °F). Here are the average temperatures.

Precipitation amounts to 1,060 millimeters (41.8 inches) per year: so, it is at an intermediate level. It ranges from 70 mm (2.8 in) in the driest months (January, February) to 105 mm (4.1 in) in the wettest (April). Here is the average precipitation.

Winter, from December to February, is cold: the average temperature is close to freezing (0 °C or 32 °F), but cold spells, during which the temperature can drop to about -15 °C (5 °F), are not rare. The wind chill can make the air feel colder than it actually is.
In recent decades, the coldest record is -21 °C (-6 °F), set in February 2016.
Snowfalls are frequent, and sometimes can be abundant, resulting in real snowstorms. The heaviest snowfall in a single day occurred on February 9, 2013, when 75 centimeters (30 inches) of snow fell. On average, 85 cm (33.6 in) of snow fall annually.
On other occasions, the wind can blow from the south, bringing some mild days, with highs around 12/15 °C (54/59 °F). There are also clear and sunny days, with cold nights, and daytime temperatures mild or in any case acceptable.

In spring, from March to May, the weather continues to be unstable: the first warm days alternate with the return of cold weather. In March, it can snow, and this can sometimes happen still in early April. But already in April, the temperature can sometimes exceed 25 °C (77 °F). By May, the average temperature becomes pleasant, although there can still be cool days, or even a little cold and rainy, while the first heat waves can bring the temperature above 30 °C (86 °F). On sunny days, the first afternoon thunderstorms can erupt.

Summer, from June to August, is hot, especially in July and August. However, there are different situations also in this season: cool days, maybe rainy as well, with highs around 23/25 °C (73/77 °F), alternate with hot days, with highs around 28/30 °C (82/86 °F). On sunny days, thunderstorms can occur in the afternoon. Sometimes, even heat waves occur, when the temperature reaches 35/36 °C (95/97 °F), and remains high at night, around 23/25 °C (73/77 °F) or above.
The highest record is 39 °C (102 °F), set in August 2001.

Autumn, from September to November, is milder and less unstable than the other seasons, at least in the first part. In early September, the weather is often still characterized by heat and humidity, with sunshine and some afternoon thunderstorms, then it quickly becomes mild and relatively quiet until mid-October, while in the second half of October, the first cold days may occur. November is by now a cold month, during which the first snowfalls may occur. There is a moderate amount of rainfall also in autumn, but it is still the season in which rainy days are a little less frequent.



The sea temperature ranges between 3.5 °C (38.5 °F) and 21.5 °C (71 °F). Here are the average sea temperatures.

Best Time

The best times to visit New Haven are spring and autumn, in order to avoid both the winter cold and the summer heat, and in particular, the month of May and from mid-September to mid-October. June is often a good month as well, but sometimes it can be hot. In early September, the weather can be sticky, though not as hot as in midsummer. In April, it can sometimes be cold and the weather can be unstable, especially at the beginning of the month, while the second half of the month is usually mild.
In autumn (usually around mid-October), in the woods north of the city, you can admire the beautiful colors of the trees losing their leaves (the phenomenon called fall foliage).

New Haven - Weather by month

Based on the period 1991-2020

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In January, the coldest month of the year, the weather in New Haven is usually very cold. The average temperature is of -0.8 °C (31 °F), with a minimum of -5 °C (23 °F) and a maximum of 3.4 °C (38.1 °F).
On the coldest nights of the month, the temperature usually drops to around -15 °C (5 °F). However, it dropped to -19.5 °C (-3.1 °F) in January 1994.
On the warmest days of the month, the temperature usually reaches around 13.5 °C (56.5 °F). However, it reached 20.6 °C (69.1 °F) in January 2020.
Precipitation amounts to 70 mm (2.8 in), distributed over 10 days.
The day lasts on average 9 hours and 35 minutes.
The average humidity is 64%.
The average wind speed is 12 kph (8 mph).
The average sea temperature is of 6 °C (43 °F). Therefore, the sea is very cold for swimming.

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In February, the weather in New Haven is usually very cold. The average temperature is of 0.0 °C (32 °F), with a minimum of -4.5 °C (23.9 °F) and a maximum of 4.6 °C (40.2 °F).
On the coldest nights of the month, the temperature usually drops to around -13 °C (8.5 °F). However, it dropped to -21.1 °C (-6 °F) in February 2016.
On the warmest days of the month, the temperature usually reaches around 12.5 °C (54.5 °F). However, it reached 19 °C (66.2 °F) in February 2011.
Precipitation amounts to 70 mm (2.8 in), distributed over 8 days.
The day lasts on average 10 hours and 40 minutes.
The average humidity is 62%.
The average wind speed is 12 kph (8 mph).
The average sea temperature is of 4 °C (39 °F). Therefore, the sea is very cold for swimming.

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In March, the weather in New Haven is usually cold. The average temperature is of 3.6 °C (39 °F), with a minimum of -1.1 °C (30.1 °F) and a maximum of 8.3 °C (47 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -9 °C (16 °F). However, it dropped to -16 °C (3.2 °F) in March 2003.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 18 °C (64 °F). However, it reached 27 °C (80.6 °F) in March 1998.
Precipitation amounts to 95 mm (3.7 in), distributed over 10 days.
The day lasts on average 12 hours and 0 minutes.
The average humidity is 61%.
The average wind speed is 13 kph (8 mph).
The average sea temperature is of 3.5 °C (38.5 °F). Therefore, the sea is very cold for swimming.

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In April, the weather in New Haven is usually mild. The average temperature is of 9.2 °C (49 °F), with a minimum of 4.1 °C (39.3 °F) and a maximum of 14.3 °C (57.8 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -2.5 °C (27.5 °F). However, it dropped to -5.6 °C (21.9 °F) in April 1995.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 24.5 °C (76.5 °F). However, it reached 30 °C (86 °F) in April 2002.
Precipitation amounts to 105 mm (4.1 in), distributed over 11 days.
The day lasts on average 13 hours and 25 minutes.
The average humidity is 63%.
The average wind speed is 12 kph (8 mph).
The average sea temperature is of 6 °C (42.5 °F). Therefore, the sea is very cold for swimming.

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In May, the weather in New Haven is usually very mild. The average temperature is of 14.8 °C (59 °F), with a minimum of 9.7 °C (49.4 °F) and a maximum of 19.8 °C (67.7 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 3 °C (38 °F). However, it dropped to -1.1 °C (30 °F) in May 2008.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 28 °C (83 °F). However, it reached 36.1 °C (97 °F) in May 1996.
Precipitation amounts to 90 mm (3.5 in), distributed over 13 days.
The day lasts on average 14 hours and 30 minutes. So the days are long.
The average humidity is 70%. Hence, the air is normally humid.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 10.5 °C (50.5 °F). Therefore, the sea is very cold for swimming.

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In June, the weather in New Haven is usually warm. The average temperature is of 19.9 °C (68 °F), with a minimum of 15.2 °C (59.3 °F) and a maximum of 24.7 °C (76.4 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 8.5 °C (47.5 °F). However, it dropped to 5.6 °C (42.1 °F) in June 2009.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 31 °C (88 °F). However, it reached 35 °C (95 °F) in June 2012.
Precipitation amounts to 90 mm (3.5 in), distributed over 12 days.
The day lasts on average 15 hours and 5 minutes. So the days are long. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 16 °C (60.5 °F). Therefore, the sea is cold for swimming.

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In July, the warmest month of the year, the weather in New Haven is usually warm to hot and muggy. The average temperature is of 23.3 °C (74 °F), with a minimum of 18.7 °C (65.7 °F) and a maximum of 27.8 °C (82.1 °F).
On the coldest nights of the month, the temperature usually drops to around 13.5 °C (56.5 °F). However, it dropped to 10 °C (50 °F) in July 2002.
On the warmest days of the month, the temperature usually reaches around 33.5 °C (92 °F). However, it reached 38 °C (100.4 °F) in July 1999.
Precipitation amounts to 85 mm (3.3 in), distributed over 10 days.
The day lasts on average 14 hours and 50 minutes. So the days are long.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 20.5 °C (69 °F). Therefore, the sea is cool for swimming.

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In August, the weather in New Haven is usually warm to hot and muggy. The average temperature is of 22.7 °C (73 °F), with a minimum of 18.2 °C (64.7 °F) and a maximum of 27.2 °C (81 °F).
On the coldest nights of the month, the temperature usually drops to around 12 °C (54 °F). However, it dropped to 11 °C (51.8 °F) in August 2000.
On the warmest days of the month, the temperature usually reaches around 32 °C (90 °F). However, it reached 39 °C (102.2 °F) in August 2001.
Precipitation amounts to 90 mm (3.5 in), distributed over 10 days.
The day lasts on average 13 hours and 40 minutes.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is 9 kph (6 mph).
The average sea temperature is of 21.5 °C (71 °F). Therefore, the sea is cool for swimming.

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In September, the weather in New Haven is usually warm. The average temperature is of 18.9 °C (66 °F), with a minimum of 14.1 °C (57.3 °F) and a maximum of 23.7 °C (74.7 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 7 °C (44.5 °F). However, it dropped to 3.3 °C (37.9 °F) in September 1991.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 30 °C (86 °F). However, it reached 33.3 °C (91.9 °F) in September 2018.
Precipitation amounts to 100 mm (3.9 in), distributed over 9 days.
The day lasts on average 12 hours and 25 minutes.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 19.5 °C (67.5 °F). Therefore, the sea is very cool for swimming.

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In October, the weather in New Haven is usually mild. The average temperature is of 12.6 °C (55 °F), with a minimum of 7.5 °C (45.5 °F) and a maximum of 17.7 °C (63.8 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -0.5 °C (31 °F). However, it dropped to -5 °C (23 °F) in October 2015.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 25.5 °C (78 °F). However, it reached 31.7 °C (89.1 °F) in October 2019.
Precipitation amounts to 95 mm (3.7 in), distributed over 11 days.
The day lasts on average 11 hours and 0 minutes.
The average humidity is 72%. Hence, the air is normally humid.
The average wind speed is 11 kph (7 mph).
The average sea temperature is of 16 °C (60.5 °F). Therefore, the sea is cold for swimming.

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In November, the weather in New Haven is usually quite mild. The average temperature is of 7.0 °C (45 °F), with a minimum of 2.2 °C (35.9 °F) and a maximum of 11.9 °C (53.4 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -5.5 °C (22 °F). However, it dropped to -10.6 °C (12.9 °F) in November 2018.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 20 °C (68 °F). However, it reached 25 °C (77 °F) in November 1993.
Precipitation amounts to 80 mm (3.1 in), distributed over 9 days.
The day lasts on average 9 hours and 50 minutes.
The average humidity is 67%.
The average wind speed is 12 kph (7 mph).
The average sea temperature is of 12 °C (54 °F). Therefore, the sea is very cold for swimming.

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In December, the weather in New Haven is usually cold. The average temperature is of 2.4 °C (36 °F), with a minimum of -1.7 °C (28.9 °F) and a maximum of 6.5 °C (43.7 °F).
On the coldest nights of the month, the temperature usually drops to around -9.5 °C (15 °F). However, it dropped to -14 °C (6.8 °F) in December 2004.
On the warmest days of the month, the temperature usually reaches around 15 °C (59.5 °F). However, it reached 24 °C (75.2 °F) in December 1998.
Precipitation amounts to 90 mm (3.5 in), distributed over 11 days.
The day lasts on average 9 hours and 10 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
The average humidity is 67%.
The average wind speed is 12 kph (8 mph).
The average sea temperature is of 9 °C (48 °F). Therefore, the sea is very cold for swimming.