Hamilton climate — normals and trends
Hamilton (Canada) has a warm-summer humid continental climate (Dfb) under the Köppen-Geiger classification. Its mean annual temperature is 8.6 °C and it receives 919 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 (21.6 °C on average) and the coldest is January (-4.2 °C). Rainfall peaks in April.
Hamilton averages 117 frost days, 4 hot days (≥ 30 °C) and 127 rainy days per year.
Hamilton has warmed by +1.6 °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 130 to 104 per year over the period.
The hottest day of the period reached 34.8 °C (on 9 August 1949) and the coldest -26.7 °C (on 16 February 2015).
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
HamiltonOntario
- coords
- 43.25°, -79.85°
- period
- 1940–2025 · 86 yrs
Mean daily temperature
8.6°C
Average daily high
12.3°C
Average daily low
5.0°C
Annual rainfall
919mm
Sunshine / day
8.7h
Mean relative humidity
72%
Average peak wind
20.3km/h
Seasonal range
25.8°C
Frost days (< 0 °C)
117 d/yr
Hot days (≥ 30 °C)
4 d/yr
Rainy days (≥ 1 mm)
127 d/yr
Annual snowfall
95.3 cm
Average feels-like high
10.0 °C
Average feels-like low
1.8 °C
Average peak gust
37.3 km/h
Tropical nights (≥ 20 °C)
17 d/yr
Solar radiation
14.1 MJ/m²
Has the climate changed?
One stripe per year, 1940 to 2025
+1.6 °C
since 1940
+0.2 °C per decade · r² = 0.28 · 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
34.8 °C
9 August 1949
Coldest day
-26.7 °C
16 February 2015
Wettest day
94 mm
15 October 1954
Windiest day
55.9 km/h
15 March 1959
Strongest gust
104.8 km/h
11 January 2017
Hottest feels-like
39.2 °C
14 July 1995
Coldest feels-like
-33.1 °C
17 January 1982
Snowiest day
28.6 cm
7 February 1942
Sunniest day
15.0 h
20 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 | -1.6 °C | -0.6 °C | 33 mm | -34 mm |
| Feb | -0.9 °C | -0.3 °C | 76 mm | +15 mm |
| Mar | 7.3 °C | +3.3 °C | 79 mm | +1 mm |
| Apr | 11.2 °C | +0.8 °C | 62 mm | -26 mm |
| May | 15.4 °C | -1.1 °C | 106 mm | +23 mm |
| Jun | 23.1 °C | +0.8 °C | 49 mm | -34 mm |
| Jul | 27.3 °C | +1.8 °C | 39 mm | -39 mm |
| Aug | 25.0 °C | +0.1 °C | 54 mm | -19 mm |
| Sep | 22.5 °C | +1.4 °C | 32 mm | -46 mm |
| Oct | 16.2 °C | +1.5 °C | 68 mm | -10 mm |
| Nov | 7.4 °C | -0.5 °C | 55 mm | -25 mm |
| Dec | 1.2 °C | -0.7 °C | 87 mm | +12 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 Hamilton?
Hamilton has a warm-summer humid continental climate (Köppen Dfb). Over 1940-2025, the average annual temperature is 8.6 °C and it receives 919 mm of precipitation per year.
What is the hottest day ever recorded in Hamilton?
The hottest day measured in Hamilton between 1940 and 2025 was 9 August 1949, reaching 34.8 °C.
What is the coldest day in Hamilton?
The coldest day measured in Hamilton between 1940 and 2025 was 16 February 2015, at -26.7 °C.
Does it snow in Hamilton?
Yes. Hamilton gets on average 95.3 cm of snow per year and has around 117 frost days.
Has the climate of Hamilton warmed?
Yes: Hamilton warmed by +1.6 °C between 1940 and 2025, a statistically significant trend.
What is the wettest day in Hamilton?
The wettest day measured in Hamilton between 1940 and 2025 was 15 October 1954, with 94 mm of rain in 24 hours.
What was the windiest day in Hamilton?
The windiest day measured in Hamilton between 1940 and 2025 was 15 March 1959, with winds reaching 55.9 km/h.
What is the warmest month in Hamilton?
The warmest month in Hamilton is July (21.6 °C on average); the coldest is January (-4.2 °C).
How much does it rain in Hamilton?
Hamilton receives on average 919 mm of precipitation per year, spread over about 127 rainy days.
Is it sunny in Hamilton?
Hamilton gets on average 8.7 hours of sunshine per day, roughly 3,175 hours per year over 1940-2025.
What is the biggest single-day snowfall in Hamilton?
The heaviest 24-hour snowfall measured in Hamilton between 1940 and 2025 was 7 February 1942, with 28.6 cm.
Are there tropical nights in Hamilton?
Yes: Hamilton has on average 17 tropical nights per year (temperature staying above 20 °C), over 1940-2025.
What was the most extreme apparent temperature in Hamilton?
In Hamilton, between 1940 and 2025, the highest apparent temperature reached 39.2 °C on 14 July 1995, and the lowest was -33.1 °C on 17 January 1982.
Compare Hamilton with another city
Pick a second city: its normals will be set against these, indicator by indicator.
Nearby cities
The climate around Hamilton