Weatheo

Boston Weather by Month

Average temperatures, rainfall and humidity for Boston, United States, month by month, built from OpenWeather’s historical records. Use it to see what a typical Boston month looks like before you travel — then check the live Boston forecast for the days ahead.

Warmest month

July

28°C average high

Coolest month

January

-4°C average low

Wettest month

October

105 mm of rain

Driest month

February

46 mm of rain

Average temperature and rainfall in Boston by month

Averages of the daily highs and lows recorded in each month, with total rainfall, mean humidity and mean wind speed.

MonthAvg highAvg lowRecord low / highRainfallHumidityWind
January3°C-4°C-21°C / 20°C
62 mm
70%16 km/h
February4°C-4°C-24°C / 22°C
46 mm
70%16 km/h
March8°C0°C-14°C / 23°C
73 mm
66%18 km/h
April14°C5°C-7°C / 31°C
77 mm
67%17 km/h
May20°C10°C1°C / 35°C
85 mm
69%15 km/h
June25°C15°C7°C / 38°C
96 mm
71%13 km/h
July28°C19°C12°C / 37°C
86 mm
74%12 km/h
August27°C18°C10°C / 36°C
67 mm
74%12 km/h
September23°C14°C4°C / 34°C
83 mm
77%13 km/h
October17°C9°C-4°C / 29°C
105 mm
77%14 km/h
November11°C3°C-11°C / 27°C
76 mm
70%15 km/h
December6°C-1°C-18°C / 19°C
88 mm
72%15 km/h

Best time to visit Boston

The most comfortable time to visit Boston is generally June and August to September, balancing mild daytime temperatures against the driest stretch of the year. The city has strongly marked seasons and rain concentrates around October, totalling about 944 mm a year.

Travellers who prefer heat should aim for July, when highs average 28°C. October is the month to avoid if rain would spoil your plans — it averages 105 mm, roughly 2× the rainfall of the driest month (February).

Source: OpenWeather historical and statistical weather data. Values are long-term averages, not a forecast — see the Boston forecast for what is happening now.