Climate - Hartford (Connecticut)

The climate of Hartford, the capital of Connecticut, is continental, with very cold, snowy winters and warm to hot summers, during which there are quite frequent thunderstorms.
The city is located in the northeastern United States, 50 km (30 mi) away from the Long Island Sound, on the banks of the Connecticut River, which gives the state its name. About 150 km (95 mi) to the east lies is the Gulf of Maine, on which a cold current flows and from which cold winds (called Nor'easters) can blow.
We are in un area where different air masses collide: those coming from Canada and those coming from the Gulf of Mexico. The result is an unstable climate, with waves of bad weather alternating with clear and sunny days.
The average temperature of the coldest month (January) is of -1.9 °C (28.6 °F), that of the warmest month (July) is of 24 °C (75.2 °F). Here are the average temperatures.

Precipitation amounts to 1,090 millimeters (42.8 inches) per year: so, it is at an intermediate level. It ranges from 65 mm (2.6 in) in the driest month (February) to 105 mm (4.1 in) in the wettest (October). Here is the average precipitation.

Winter, from December to mid-March, is very cold: the average temperature is slightly below freezing (0 °C or 32 °F), but cold spells, with temperatures dropping to -15 °C (5 °F) or even below, are not uncommon. On the coldest nights of the year, the temperature typically drops to around -20 °C (-4 °F). The cold record is -26 °C (-15 °F), recorded in January 1961. From 2001 to 2020, the record was -23.5 °C (-10 °F) set in January 2018.
The freezing wind, called blizzard, can heighten the feeling of cold.
Snowfalls are frequent, and sometimes can be abundant. The heaviest snowfall in a single day occurred on January 12, 2011, when 61 centimeters (24 inches) of snow fell. Snow covers the ground for weeks. It usually snows from October through April.
On other occasions, the south wind can bring some mild days, during which highs can reach 12/15 °C (54/59 °F), but this occurs less frequently than in New York.

In spring, from mid-March to mid-June, the weather continues to be unstable: the first warm days alternate with the return of cold weather. In March, which is often still a wintery month, it snows on a frequent basis, and sometimes, this can happen even in April, especially at the beginning of the month. But already in April, the temperature can sometimes reach or even exceed 25 °C (77 °F).
By May, the average temperature is pleasant, although there are still cool days, or even cold and rainy, while the first heat waves can raise the temperature above 30 °C (86 °F). On sunny days, also the first afternoon thunderstorms can erupt.

Summer, from mid-June to August, is warm to hot and humid. Different situations can occur in this season as well: there are cool days, maybe with some rain, and with highs around 23/24 °C (73/75 °F), but also hot, sunny and quite muggy days, with highs around 28/30 °C (82/86 °F).
Sometimes, even heat waves can occur, with daytime temperatures reaching or exceeding 35 °C (95 °F), and night temperatures remaining around 23/25 °C (73/77 °F). The heat record is 39.5 °C (103 °F), set in July 2011 and in August 2001.
The amount of sunshine during the summer is good, however, in addition to some weather fronts, there is a fair amount of afternoon thunderstorms, sometimes intense and accompanied by hail.

Autumn, from September to November, is the mildest and less unstable season of the year, at least in the first part. In early September, the weather can still be characterized by heat and humidity, with sunshine and some afternoon thunderstorms, then it quickly becomes mild until mid-October, while in the second half of October, it can start to be a bit cold. November is already a cold month, and the first snowfalls can occur. Rainfall occurs quite often also in this season.



On average, there are around 2,585 sunshine hours per year. Here are the average sunshine hours per day.

Best Time

In order to avoid both the winter cold and the summer heat, the best times to visit Hartford are spring and autumn, and in particular, the month of May and from early September to early October. June is often a good month too, but we can not exclude some hot days. In early September, the weather is often hot and humid, although not as hot as in midsummer. In May, it can sometimes get cold, and the weather can be unstable, especially at the beginning of the month, while generally, the second half of the month is mild.
In autumn (usually around late October), you can admire the beautiful colors of the trees losing their leaves (the phenomenon called fall foliage).

Hartford - Weather by month

Based on the period 1991-2020

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In January, the coldest month of the year, the weather in Hartford is usually very cold. The average temperature is of -1.9 °C (29 °F), with a minimum of -6.5 °C (20.3 °F) and a maximum of 2.7 °C (36.8 °F).
On the coldest nights of the month, the temperature usually drops to around -16 °C (3 °F). However, it dropped to -23.3 °C (-9.9 °F) in January 2018.
On the warmest days of the month, the temperature usually reaches around 15 °C (58.5 °F). However, it reached 22 °C (71.6 °F) in January 2007.
Precipitation amounts to 75 mm (3 in), distributed over 10 days.
The day lasts on average 9 hours and 35 minutes.
There are on average 5.5 hours of sunshine per day. So, the sun shines 57% of the time.
The average humidity is 64%.
The average wind speed is 11 kph (7 mph).

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In February, the weather in Hartford is usually very cold. The average temperature is of -0.7 °C (31 °F), with a minimum of -5.5 °C (22.1 °F) and a maximum of 4.2 °C (39.5 °F).
On the coldest nights of the month, the temperature usually drops to around -14 °C (6.5 °F). However, it dropped to -22.8 °C (-9 °F) in February 2016.
On the warmest days of the month, the temperature usually reaches around 15 °C (58.5 °F). However, it reached 22.8 °C (73 °F) in February 2018.
Precipitation amounts to 65 mm (2.6 in), distributed over 9 days.
The day lasts on average 10 hours and 35 minutes.
There are on average 6.5 hours of sunshine per day. So, the sun shines 59% of the time.
The average humidity is 60%.
The average wind speed is 12 kph (7 mph).

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In March, the weather in Hartford is usually cold. The average temperature is of 3.7 °C (39 °F), with a minimum of -1.3 °C (29.6 °F) and a maximum of 8.7 °C (47.6 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -9.5 °C (15 °F). However, it dropped to -17.2 °C (1 °F) in March 2003.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 19.5 °C (67.5 °F). However, it reached 28.3 °C (82.9 °F) in March 1998.
Precipitation amounts to 90 mm (3.5 in), distributed over 10 days.
The day lasts on average 12 hours and 0 minutes.
There are on average 7 hours of sunshine per day. So, the sun shines 57% of the time.
The average humidity is 58%.
The average wind speed is 13 kph (8 mph).

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In April, the weather in Hartford is usually mild. The average temperature is of 10.0 °C (50 °F), with a minimum of 4.4 °C (40 °F) and a maximum of 15.6 °C (60.1 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -2 °C (28 °F). However, it dropped to -6.7 °C (19.9 °F) in April 1995.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 27 °C (81 °F). However, it reached 34.4 °C (93.9 °F) in April 2002.
Precipitation amounts to 95 mm (3.7 in), distributed over 11 days.
The day lasts on average 13 hours and 25 minutes.
There are on average 7.5 hours of sunshine per day. So, the sun shines 57% of the time.
The average humidity is 56%.
The average wind speed is 13 kph (8 mph).

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In May, the weather in Hartford is usually very mild. The average temperature is of 15.8 °C (61 °F), with a minimum of 10.1 °C (50.1 °F) and a maximum of 21.6 °C (70.9 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 3 °C (37.5 °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 31.5 °C (89 °F). However, it reached 37.2 °C (99 °F) in May 2010.
Precipitation amounts to 85 mm (3.3 in), distributed over 13 days.
The day lasts on average 14 hours and 35 minutes. So the days are long.
There are on average 8.5 hours of sunshine per day. So, the sun shines 57% of the time.
The average humidity is 62%.
The average wind speed is 11 kph (7 mph).

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In June, the weather in Hartford is usually warm. The average temperature is of 20.9 °C (70 °F), with a minimum of 15.4 °C (59.8 °F) and a maximum of 26.4 °C (79.6 °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 3.9 °C (39 °F) in June 2001.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 33.5 °C (92.5 °F). However, it reached 36.7 °C (98.1 °F) in June 1999.
Precipitation amounts to 100 mm (3.9 in), distributed over 11 days.
The day lasts on average 15 hours and 10 minutes. So the days are long. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
There are on average 9 hours of sunshine per day. So, the sun shines 60% of the time.
The average humidity is 66%.
The average wind speed is 10 kph (6 mph).

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In July, the warmest month of the year, the weather in Hartford is usually warm to hot. The average temperature is of 24.0 °C (75 °F), with a minimum of 18.7 °C (65.7 °F) and a maximum of 29.2 °C (84.6 °F).
On the coldest nights of the month, the temperature usually drops to around 13 °C (56 °F). However, it dropped to 9.4 °C (48.9 °F) in July 2001.
On the warmest days of the month, the temperature usually reaches around 35 °C (95 °F). However, it reached 39.4 °C (102.9 °F) in July 2011.
Precipitation amounts to 100 mm (3.9 in), distributed over 11 days.
The day lasts on average 14 hours and 50 minutes. So the days are long.
There are on average 9.5 hours of sunshine per day. So, the sun shines 64% of the time.
The average humidity is 68%.
The average wind speed is 10 kph (6 mph).

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In August, the weather in Hartford is usually warm to hot. The average temperature is of 23.1 °C (74 °F), with a minimum of 17.9 °C (64.2 °F) and a maximum of 28.3 °C (83 °F).
On the coldest nights of the month, the temperature usually drops to around 12 °C (53.5 °F). However, it dropped to 8.9 °C (48 °F) in August 2000.
On the warmest days of the month, the temperature usually reaches around 34 °C (93 °F). However, it reached 39.4 °C (102.9 °F) in August 2001.
Precipitation amounts to 90 mm (3.5 in), distributed over 10 days.
The day lasts on average 13 hours and 50 minutes.
There are on average 8.5 hours of sunshine per day. So, the sun shines 63% of the time.
The average humidity is 69%.
The average wind speed is 9 kph (6 mph).

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In September, the weather in Hartford is usually warm. The average temperature is of 18.8 °C (66 °F), with a minimum of 13.3 °C (56 °F) and a maximum of 24.2 °C (75.6 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 5.5 °C (42 °F). However, it dropped to 1 °C (33.8 °F) in September 2000.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 31.5 °C (88.5 °F). However, it reached 35.6 °C (96.1 °F) in September 2015.
Precipitation amounts to 100 mm (3.9 in), distributed over 10 days.
The day lasts on average 12 hours and 25 minutes.
There are on average 7.5 hours of sunshine per day. So, the sun shines 60% of the time.
The average humidity is 71%. Hence, the air is normally humid.
The average wind speed is 9 kph (6 mph).

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In October, the weather in Hartford is usually mild. The average temperature is of 12.2 °C (54 °F), with a minimum of 6.8 °C (44.3 °F) and a maximum of 17.6 °C (63.7 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -1 °C (30 °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 26.5 °C (79.5 °F). However, it reached 31.1 °C (88 °F) in October 2007.
Precipitation amounts to 105 mm (4.1 in), distributed over 11 days.
The day lasts on average 11 hours and 0 minutes.
There are on average 6.5 hours of sunshine per day. So, the sun shines 58% of the time.
The average humidity is 70%. Hence, the air is normally humid.
The average wind speed is 10 kph (6 mph).

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In November, the weather in Hartford is usually quite cold. The average temperature is of 6.3 °C (43 °F), with a minimum of 1.4 °C (34.6 °F) and a maximum of 11.2 °C (52.1 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -6 °C (21 °F). However, it dropped to -12.2 °C (10 °F) in November 2018.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 21.5 °C (70.5 °F). However, it reached 26.1 °C (79 °F) in November 1993.
Precipitation amounts to 85 mm (3.3 in), distributed over 10 days.
The day lasts on average 9 hours and 50 minutes.
There are on average 4.5 hours of sunshine per day. So, the sun shines 47% of the time.
The average humidity is 66%.
The average wind speed is 10 kph (6 mph).

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In December, the weather in Hartford is usually cold. The average temperature is of 1.0 °C (34 °F), with a minimum of -3.4 °C (25.9 °F) and a maximum of 5.4 °C (41.7 °F).
On the coldest nights of the month, the temperature usually drops to around -11.5 °C (11.5 °F). However, it dropped to -16.1 °C (3 °F) in December 2017.
On the warmest days of the month, the temperature usually reaches around 16 °C (61 °F). However, it reached 24 °C (75.2 °F) in December 1998.
Precipitation amounts to 95 mm (3.7 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.
There are on average 4.5 hours of sunshine per day. So, the sun shines 49% of the time.
The average humidity is 67%.
The average wind speed is 10 kph (7 mph).