Hartford Weather in September
During September, Hartford experiences high daytime temperatures of 25°C (77°F) and cooler nights around 13°C (55°F). Expect quite a bit of rainfall. Around 90 mm (3.5 in) is typical.
Rainfall in Hartford in September
The climate data from previous years indicates about 8 days of rain, averaging 90 mm (3.5 in) for the month. Rainfall intensity is on the higher side this month. Expect more substantial showers rather than light, passing rain.
Temperature in Hartford in September
September is a good time to be in Hartford. Days are perfect, reaching 25°C (77°F), with nights around 13°C (55°F). Overall, the month follows a fairly predictable daily temperature pattern. With lows of 13°C (55°F), nights are cool. If you're out after dark, an extra layer will keep you comfortable. The cooler air at night is also great for getting a good rest.
Sunshine in Hartford in September
Expect a lot of sunshine this month, with about 223 hours of sun. These sunny conditions add to the overall experience.If you're a fan of comfortable temperatures and drier conditions, September is a great time to visit.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the United States of America, check out our Hartford's climate page.
Hartford Temperature in September
Min Temperature
13°C (55°F)
Max Temperature
25°C (77°F)
Chance of Rain
27%
Precipitation
90 mm (3.5 in)
Rainy days
8 days
Humidity
72%
Sunshine
223 hours
Percentage Sunshine
60%
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Hartford typically drop from around 26°C (79°F) at the start of September to approximately 21°C (70°F) by the end. Nights are cool, with lows typically ranging from 9°C (48°F) to 16°C (61°F).
Average temperatures in September
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in September
Historical weather for Hartford in September
Browse day-by-day weather records for Hartford spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Hartford historical weather extremes in September
Based on 49 years of weather observations in Hartford between 1976 and 2025, these are the recorded extremes.
- On September 11, 1983, temperatures climbed to 37°C (99°F), marking the warmest September day on record.
- Hartford experienced its chilliest September day on September 26, 2000, reaching only 11°C (52°F).
- The lowest overnight temperature recorded in September was -1°C (30°F) (September 29, 2000).
Best Places in the United States of America in September
Find out more about the weather in the United States of America and which places have the best travel conditions in this month. See all of the United States of America in September →
perfect weather
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What to Wear in Hartford in September
For Hartford in September, you'll want flexible clothing. It's wise to pack cotton shirts, comfortable shorts, and a pair of jeans for cooler evenings. A light sweater or jacket is useful for air-conditioned spaces (like buses) or unexpected cool moments. High rain levels are expected, so pack waterproof gear and an umbrella or poncho. You'll definitely want to pack sunglasses and sunscreen. There will be plenty of bright sunshine this month.What To Do in Hartford in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit the United States of America, check out our Hartford's climate page.
Temperature Rainfall Sunshine Humidity
See the full Hartford climate overview or explore weather in the United States of America.
