Yosemite National Park is definitely worth a visit
Vast forests, blue lakes, towering sequoias, and majestic waterfalls hint at the beauty of Yosemite National Park—a true natural masterpiece.
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.
If you're a fan of comfortable temperatures and drier conditions, September is a great time to visit.
Pick a month to see the average temperature, rainfall and sunshine in Hartford - and find the best time to visit.
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).
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
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.
Based on 49 years of weather observations in Hartford between 1976 and 2025, these are the recorded extremes.
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 is subjective. On this map perfect weather has been defined with temperatures between 20°C (68°F) and 29°C (84°F) and not too much precipitation (less than 90 mm (3.5 in) a month).
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.
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Temperature Rainfall Sunshine Humidity
See the full Hartford climate overview or explore weather in the United States of America.
Where to go in September - average daytime high across popular destinations.
Need travel inspiration? Check out our bucket list articles and be inspired.
Yosemite National Park is definitely worth a visit
Vast forests, blue lakes, towering sequoias, and majestic waterfalls hint at the beauty of Yosemite National Park—a true natural masterpiece.
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