Westerly climate — normals and trends
Westerly (United States) has a hot-summer humid continental climate (Dfa) under the Köppen-Geiger classification. Its mean annual temperature is 10.7 °C and it receives 1,128 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 (22.5 °C on average) and the coldest is January (-1.0 °C). Rainfall peaks in December.
Westerly averages 83 frost days, 7 hot days (≥ 30 °C) and 119 rainy days per year.
Westerly has warmed by +1.5 °C between 1940 and 2025, or +0.18 °C per decade. This trend is statistically significant.
The number of frost days there went from about 91 to 75 per year over the period.
The hottest day of the period reached 36.9 °C (on 5 July 1999) and the coldest -24.0 °C (on 13 February 1967).
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
WesterlyRhode Island
- coords
- 41.38°, -71.83°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
10.7°C
Average daily high
14.4°C
Average daily low
7.2°C
Annual rainfall
1,128mm
Sunshine / day
8.9h
Mean relative humidity
72%
Average peak wind
18.7km/h
Seasonal range
23.5°C
Frost days (< 0 °C)
83 d/yr
Hot days (≥ 30 °C)
7 d/yr
Rainy days (≥ 1 mm)
119 d/yr
Annual snowfall
75.8 cm
Average feels-like high
12.7 °C
Average feels-like low
4.5 °C
Average peak gust
42.1 km/h
Tropical nights (≥ 20 °C)
25 d/yr
Solar radiation
14.7 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.5 °C
since 1940
+0.2 °C per decade · r² = 0.39 · 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
36.9 °C
5 July 1999
Coldest day
-24.0 °C
13 February 1967
Wettest day
122 mm
26 September 2008
Windiest day
63.3 km/h
12 September 1960
Strongest gust
141.5 km/h
25 November 1950
Hottest feels-like
43.4 °C
27 August 1948
Coldest feels-like
-29.8 °C
14 February 2016
Snowiest day
35.7 cm
4 February 1961
Sunniest day
14.7 h
13 June 2008
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 | 1.7 °C | -0.8 °C | 48 mm | -48 mm |
| Feb | 3.4 °C | +0.1 °C | 80 mm | -7 mm |
| Mar | 9.6 °C | +2.5 °C | 114 mm | +10 mm |
| Apr | 14.1 °C | +1.6 °C | 96 mm | -1 mm |
| May | 18.1 °C | +0.2 °C | 157 mm | +64 mm |
| Jun | 24.2 °C | +1.3 °C | 42 mm | -41 mm |
| Jul | 27.6 °C | +1.3 °C | 80 mm | -2 mm |
| Aug | 25.2 °C | -0.4 °C | 61 mm | -36 mm |
| Sep | 22.9 °C | +1.0 °C | 56 mm | -34 mm |
| Oct | 16.9 °C | +0.4 °C | 103 mm | +11 mm |
| Nov | 10.5 °C | -0.3 °C | 60 mm | -43 mm |
| Dec | 3.7 °C | -1.5 °C | 82 mm | -24 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 Westerly?
Westerly has a hot-summer humid continental climate (Köppen Dfa). Over 1940-2025, the average annual temperature is 10.7 °C and it receives 1,128 mm of precipitation per year.
What is the hottest day ever recorded in Westerly?
The hottest day measured in Westerly between 1940 and 2025 was 5 July 1999, reaching 36.9 °C.
What is the coldest day in Westerly?
The coldest day measured in Westerly between 1940 and 2025 was 13 February 1967, at -24.0 °C.
Does it snow in Westerly?
Yes. Westerly gets on average 75.8 cm of snow per year and has around 83 frost days.
Has the climate of Westerly warmed?
Yes: Westerly warmed by +1.5 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Westerly?
The wettest day measured in Westerly between 1940 and 2025 was 26 September 2008, with 122 mm of rain in 24 hours.
What was the windiest day in Westerly?
The windiest day measured in Westerly between 1940 and 2025 was 12 September 1960, with winds reaching 63.3 km/h.
What is the warmest month in Westerly?
The warmest month in Westerly is July (22.5 °C on average); the coldest is January (-1.0 °C).
How much does it rain in Westerly?
Westerly receives on average 1,128 mm of precipitation per year, spread over about 119 rainy days.
Is it sunny in Westerly?
Westerly gets on average 8.9 hours of sunshine per day, roughly 3,249 hours per year over 1940-2025.
What is the biggest single-day snowfall in Westerly?
The heaviest 24-hour snowfall measured in Westerly between 1940 and 2025 was 4 February 1961, with 35.7 cm.
Are there tropical nights in Westerly?
Yes: Westerly has on average 25 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Westerly?
In Westerly, between 1940 and 2025, the highest apparent temperature reached 43.4 °C on 27 August 1948, and the lowest was -29.8 °C on 14 February 2016.
Compare Westerly with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Westerly