Monthly climate ·Boston weather in September
In September, Boston averages around 23° by day and 15° at night, with 10 rain days a month — about a 32% chance of rain on any given day.
By day
23°C
At night
15°C
Daily rain chance
32%
Rain days a month
10
Monthly precipitation
108 mm
Sunshine hours a day
8.9
Average of 2016–2025 (Open-Meteo archive). Typical climate — not a forecast.
Is September a good time to visit Boston?
September is pleasant in Boston: around 23° by day and 15° at night — comfortable weather for exploring, with 10 rain days on average.
Every month in Boston
Frequently asked questions
- What is the weather in Boston in September?
- In September, temperatures in Boston average between 15° at night and 23° by day, with 10 rain days a month (average of 2016–2025).
- How much rain falls in Boston in September?
- Boston gets about 108 mm of rain in September on average, spread over roughly 10 rain days.
- Is September a good time to visit Boston?
- September is pleasant in Boston: around 23° by day and 15° at night — comfortable weather for exploring, with 10 rain days on average.