Worcester climate — normals and trends
Worcester (United States) has a hot-summer humid continental climate (Dfa) under the Köppen-Geiger classification. Its mean annual temperature is 9.5 °C and it receives 1,121 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 (22.3 °C on average) and the coldest is January (-3.4 °C). Rainfall peaks in March.
Worcester averages 115 frost days, 18 hot days (≥ 30 °C) and 123 rainy days per year.
Worcester has warmed by +1.7 °C between 1940 and 2025, or +0.20 °C per decade. This trend is statistically significant.
The number of frost days there went from about 124 to 106 per year over the period.
The hottest day of the period reached 38.7 °C (on 22 July 2011) and the coldest -27.0 °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
WorcesterMassachusetts
- coords
- 42.26°, -71.80°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
9.5°C
Average daily high
14.2°C
Average daily low
5.1°C
Annual rainfall
1,121mm
Sunshine / day
8.6h
Mean relative humidity
69%
Average peak wind
17.3km/h
Seasonal range
25.7°C
Frost days (< 0 °C)
115 d/yr
Hot days (≥ 30 °C)
18 d/yr
Rainy days (≥ 1 mm)
123 d/yr
Annual snowfall
122.1 cm
Average feels-like high
12.1 °C
Average feels-like low
2.1 °C
Average peak gust
40.8 km/h
Tropical nights (≥ 20 °C)
16 d/yr
Solar radiation
14.1 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.7 °C
since 1940
+0.2 °C per decade · r² = 0.42 · 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
38.7 °C
22 July 2011
Coldest day
-27.0 °C
13 February 1967
Wettest day
183 mm
19 August 1955
Windiest day
54.0 km/h
19 August 1991
Strongest gust
128.9 km/h
25 November 1950
Hottest feels-like
42.5 °C
2 August 1975
Coldest feels-like
-32.6 °C
13 February 1967
Snowiest day
44.4 cm
12 December 1992
Sunniest day
14.7 h
21 June 2025
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 | 0.3 °C | -0.4 °C | 48 mm | -41 mm |
| Feb | 1.6 °C | -0.4 °C | 88 mm | +4 mm |
| Mar | 10.0 °C | +3.3 °C | 99 mm | -2 mm |
| Apr | 15.2 °C | +2.0 °C | 101 mm | +5 mm |
| May | 19.1 °C | -0.2 °C | 207 mm | +113 mm |
| Jun | 25.3 °C | +1.0 °C | 78 mm | -17 mm |
| Jul | 28.9 °C | +1.6 °C | 95 mm | +3 mm |
| Aug | 26.4 °C | +0.2 °C | 47 mm | -50 mm |
| Sep | 23.3 °C | +1.3 °C | 81 mm | -7 mm |
| Oct | 16.5 °C | +0.6 °C | 97 mm | +8 mm |
| Nov | 9.0 °C | -0.5 °C | 71 mm | -26 mm |
| Dec | 1.7 °C | -1.5 °C | 82 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 Worcester?
Worcester has a hot-summer humid continental climate (Köppen Dfa). Over 1940-2025, the average annual temperature is 9.5 °C and it receives 1,121 mm of precipitation per year.
What is the hottest day ever recorded in Worcester?
The hottest day measured in Worcester between 1940 and 2025 was 22 July 2011, reaching 38.7 °C.
What is the coldest day in Worcester?
The coldest day measured in Worcester between 1940 and 2025 was 13 February 1967, at -27.0 °C.
Does it snow in Worcester?
Yes. Worcester gets on average 122.1 cm of snow per year and has around 115 frost days.
Has the climate of Worcester warmed?
Yes: Worcester warmed by +1.7 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Worcester?
The wettest day measured in Worcester between 1940 and 2025 was 19 August 1955, with 183 mm of rain in 24 hours.
What was the windiest day in Worcester?
The windiest day measured in Worcester between 1940 and 2025 was 19 August 1991, with winds reaching 54.0 km/h.
What is the warmest month in Worcester?
The warmest month in Worcester is July (22.3 °C on average); the coldest is January (-3.4 °C).
How much does it rain in Worcester?
Worcester receives on average 1,121 mm of precipitation per year, spread over about 123 rainy days.
Is it sunny in Worcester?
Worcester gets on average 8.6 hours of sunshine per day, roughly 3,139 hours per year over 1940-2025.
What is the biggest single-day snowfall in Worcester?
The heaviest 24-hour snowfall measured in Worcester between 1940 and 2025 was 12 December 1992, with 44.4 cm.
Are there tropical nights in Worcester?
Yes: Worcester has on average 16 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Worcester?
In Worcester, between 1940 and 2025, the highest apparent temperature reached 42.5 °C on 2 August 1975, and the lowest was -32.6 °C on 13 February 1967.
Compare Worcester with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Worcester