Photo: P199 · CC BY-SA 3.0Frost comes to Hamilton less often than to 85% of Canadian towns
Peak summer warmth arrives in July, with afternoons near 23.6°C. In July, afternoons here are cooler than in 72% of Canadian towns. A year here swings 32°C from midwinter lows to midsummer highs. The heating season runs October to April: each of those months averages under 10°C.
No ECCC station in Hamilton has 1991–2020 normals; the page reads Cobourg, 12 km south, instead.
A year in Hamilton at a glance
Each month’s typical high and low, in °C.
What stands out about Hamilton’s climate
Compared with Canadian towns, with its place among towns of 2,500+ in Ontario beside it.
What a year in Hamilton feels like
Typical highs and lows by season and by month, from ECCC’s 1991–2020 normals.
About 126 frosts a year
Frosts fall from October to April; January has the most, about 27.
Frost days by month
Average days at 0°C or below
Rain and melted snow: about 840 mm a year
June brings the most rain and snow; February, the least. On about 114 days a year, 1 mm or more falls.
Rain and snow by month
Millimetres
Rain alone by month
Millimetres
ECCC’s Cobourg normals leave out precipitation and snow; both come from Peterborough here, 23 km away.
About 158 cm of snow a year
From October to April snow is likely; January is the peak, at about 45 cm.
Snowfall by month
Centimetres
Living with Hamilton’s climate
Gardening, time outside, winter cold and summer heat, from the 1991–2020 normals.
For long days outdoors, Jun, Jul, Aug and Sep bring highs of 17–27°C and lows of 8°C or more.
Parks & trails →Roughly 18 days a year feel colder than −20 in the wind.
About 33 days a year feel above 30 on the humidex.
Bad-weather days, from blizzards to floods, get their own page for Hamilton: the hazards page.
Flood & hazards →ECCC’s normals location: Cobourg
Every temperature, frost, snow and degree-day figure on this page is the 1991–2020 normal ECCC publishes for Cobourg.
| Distance from the town | 12 km south |
| Station altitude | 78 m |
| Completeness | at least 20 years |
| WMO standard normals | No |
| Precipitation from | Peterborough, 23 km |
| Coldest reading, 1991–2020 | −27.4°C |
| Hottest reading, 1991–2020 | 34.0°C |
| Average wind | 11.7 km/h on average, most often from the west |
| Next-nearest location | Peterborough, 23 km |
How Hamilton compares
Placed among 2,611 Canadian towns and neighbourhoods of 2,500+, each on its nearest normals location; each dot is another location used in Ontario.
Nearby towns’ climate
Nearby places read from a different ECCC location (places on Hamilton’s own would show the same figures). No closer place has figures: this one lies 20 km from Hamilton.
| Town | July high | January low | Rain & snow |
|---|---|---|---|
| Hamilton Cobourg | 23.6°C | −8.7°C | 840 mm |
| Otonabee-South Monaghan 20 km · Peterborough | 26.6°C 3.0°C warmer | −12.8°C 4.1°C colder | 840 mm |
Hamilton weather by month
Month by month, 1991–2020: the usual high, low and mean, the rain and snow, and the snowfall.
| Month | High | Low | Mean | Rain & snow | Snow |
|---|---|---|---|---|---|
| January | −1.1°C | −8.7°C | −4.9°C | 67 mm | 45 cm |
| February | −0.4°C | −8.1°C | −4.3°C | 42 mm | 27 cm |
| March | 3.4°C | −3.9°C | −0.3°C | 54 mm | 28 cm |
| April | 9.6°C | 2.0°C | 5.8°C | 73 mm | 7 cm |
| May | 15.4°C | 7.4°C | 11.4°C | 79 mm | 0 cm |
| June | 20.4°C | 12.4°C | 16.4°C | 88 mm | 0 cm |
| July | 23.6°C | 15.9°C | 19.8°C | 69 mm | 0 cm |
| August | 23.6°C | 15.8°C | 19.7°C | 78 mm | 0 cm |
| September | 20.4°C | 12.2°C | 16.3°C | 76 mm | 0 cm |
| October | 13.3°C | 6.0°C | 9.6°C | 75 mm | 1 cm |
| November | 7.2°C | 0.3°C | 3.8°C | 76 mm | 17 cm |
| December | 1.8°C | −4.8°C | −1.5°C | 64 mm | 33 cm |
| Year | 11.4°C | 3.9°C | 7.7°C | 840 mm | 158 cm |
March: −25.2°C at its coldest, 18.8°C at its warmest
The month to count on least is January: one year in three its average strays more than 2.8°C from −4.9°C. June moves least, typically by 0.9°C.
Where Hamilton’s numbers come from
Averages over 30 years, not a forecast.
- Normals: ECCC’s normals for Cobourg, 1991–2020, chosen as the nearest location with a full temperature record.
- Other locations: precipitation and snowfall come from the nearest location that publishes all twelve months of them, as named above.
- Comparisons: every place of 2,500+ in Canada but the city hubs and the reserves, each on its nearest ECCC location.
- Not on this page: sunshine, which none of ECCC’s 450 locations publishes for 1991–2020, and the town’s own height above sea level, so no figure is adjusted for altitude.
Canadian Climate Normals 1991–2020 · ECCC Data Services End-use Licence. Data Source: Environment and Climate Change Canada
Questions about Hamilton’s climate
How warm does Hamilton get in summer?
Of all twelve months, July has the warmest afternoons, about 23.6°C.
How cold does Hamilton get in winter?
In January, the coldest month, the typical low is −8.7°C.
How much rain and snow does Hamilton get?
Some 840 mm falls in a year. Most of it comes in June (88 mm), the least in February (42 mm).
Are these figures for Hamilton itself?
The figures are ECCC’s for Cobourg; Hamilton has no normals station.
Data Source: Environment and Climate Change Canada · ECCC Data Services End-use Licence Today’s forecast for Hamilton →
Adapted from Statistics Canada (Census of Population 2021, population estimates 2025, 2021 census boundaries) under the Statistics Canada Open Licence; this does not constitute an endorsement by Statistics Canada. Neighbourhood names in some cities © OpenStreetMap contributors (ODbL).