Boston climate — normals and trends
Boston (United Kingdom) has a temperate oceanic climate (Cfb) under the Köppen-Geiger classification. Its mean annual temperature is 10.0 °C and it receives 610 mm of precipitation per year.
These figures are normals computed over 86 complete calendar years, from 1940 to 2025, using ERA5 reanalysis data from the Copernicus programme.
The warmest month is July (16.7 °C on average) and the coldest is January (4.0 °C). Rainfall peaks in August.
Boston averages 30 frost days, 0 hot days (≥ 30 °C) and 126 rainy days per year.
Boston has warmed by +1.6 °C between 1940 and 2025, or +0.19 °C per decade. This trend is statistically significant.
The number of frost days there went from about 46 to 14 per year over the period.
The hottest day of the period reached 38.1 °C (on 19 July 2022) and the coldest -15.9 °C (on 23 January 1963).
Data from ERA5 reanalysis (Copernicus Climate Change Service), redistributed under a CC-BY 4.0 licence. Normals are recomputed whenever the archive is updated.
Climate normals · ERA5
BostonEngland
- coords
- 52.98°, -0.03°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
10.0°C
Average daily high
13.0°C
Average daily low
7.0°C
Annual rainfall
610mm
Sunshine / day
7.2h
Mean relative humidity
81%
Average peak wind
23.7km/h
Seasonal range
12.7°C
Frost days (< 0 °C)
30 d/yr
Hot days (≥ 30 °C)
0 d/yr
Rainy days (≥ 1 mm)
126 d/yr
Annual snowfall
14.1 cm
Average feels-like high
10.0 °C
Average feels-like low
3.7 °C
Average peak gust
41.8 km/h
Tropical nights (≥ 20 °C)
0 d/yr
Solar radiation
10.2 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.6 °C
since 1940
+0.2 °C per decade · r² = 0.45 · p = < 0.001
Trend fitted by linear regression (ordinary least squares) on annual means. A trend is shown only when it is statistically significant (p < 0.05).
A climograph overlays rainfall (bars) and temperature (line): the standard reading in climatology, where you can see at a glance whether the warm season is also the dry one.
Records for the period
Hottest day
38.1 °C
19 July 2022
Coldest day
-15.9 °C
23 January 1963
Wettest day
45 mm
20 October 2023
Windiest day
69.5 km/h
3 January 1976
Strongest gust
126.4 km/h
9 February 2020
Hottest feels-like
35.9 °C
25 July 2019
Coldest feels-like
-21.0 °C
23 January 1963
Snowiest day
11.3 cm
25 February 1958
Sunniest day
16.0 h
3 June 1940
Normals computed over complete calendar years 1940–2025.
A specific year
Pick a year and see how it compares to normal — warmer, drier or more extreme than usual?
Across the whole year
Month by month
| High | vs. normal | Precipitation | vs. normal | |
|---|---|---|---|---|
| Jan | 6.1 °C | -0.1 °C | 73 mm | +25 mm |
| Feb | 7.5 °C | +0.6 °C | 42 mm | +1 mm |
| Mar | 12.3 °C | +3.1 °C | 13 mm | -32 mm |
| Apr | 14.7 °C | +2.9 °C | 15 mm | -32 mm |
| May | 16.9 °C | +1.9 °C | 26 mm | -29 mm |
| Jun | 22.9 °C | +4.7 °C | 39 mm | -15 mm |
| Jul | 22.7 °C | +2.4 °C | 72 mm | +16 mm |
| Aug | 22.1 °C | +1.9 °C | 23 mm | -36 mm |
| Sep | 18.5 °C | +0.7 °C | 67 mm | +15 mm |
| Oct | 14.1 °C | +0.1 °C | 65 mm | +12 mm |
| Nov | 11.0 °C | +1.5 °C | 104 mm | +51 mm |
| Dec | 9.3 °C | +2.1 °C | 68 mm | +19 mm |
The year's extremes
What was the weather like that day?
Your birthday, a wedding, a memorable trip: discover the actual weather for any date since 1940.
Frequently asked questions
What is the climate of Boston?
Boston has a temperate oceanic climate (Köppen Cfb). Over 1940-2025, the average annual temperature is 10.0 °C and it receives 610 mm of precipitation per year.
What is the hottest day ever recorded in Boston?
The hottest day measured in Boston between 1940 and 2025 was 19 July 2022, reaching 38.1 °C.
What is the coldest day in Boston?
The coldest day measured in Boston between 1940 and 2025 was 23 January 1963, at -15.9 °C.
Does it snow in Boston?
Yes. Boston gets on average 14.1 cm of snow per year and has around 30 frost days.
Has the climate of Boston warmed?
Yes: Boston warmed by +1.6 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Boston?
The wettest day measured in Boston between 1940 and 2025 was 20 October 2023, with 45 mm of rain in 24 hours.
What was the windiest day in Boston?
The windiest day measured in Boston between 1940 and 2025 was 3 January 1976, with winds reaching 69.5 km/h.
What is the warmest month in Boston?
The warmest month in Boston is July (16.7 °C on average); the coldest is January (4.0 °C).
How much does it rain in Boston?
Boston receives on average 610 mm of precipitation per year, spread over about 126 rainy days.
Is it sunny in Boston?
Boston gets on average 7.2 hours of sunshine per day, roughly 2,628 hours per year over 1940-2025.
What is the biggest single-day snowfall in Boston?
The heaviest 24-hour snowfall measured in Boston between 1940 and 2025 was 25 February 1958, with 11.3 cm.
Are there tropical nights in Boston?
Almost never: tropical nights (temperature staying above 20 °C) are virtually non-existent in Boston.
What was the most extreme apparent temperature in Boston?
In Boston, between 1940 and 2025, the highest apparent temperature reached 35.9 °C on 25 July 2019, and the lowest was -21.0 °C on 23 January 1963.
Compare Boston with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Boston