Frost comes to Mount Dennis less often than to 89% of Canadian towns
In July the day’s top temperature is typically 27.0°C. Summer afternoons here are warmer than in 86% of Canadian towns. Winter and summer sit 34°C apart. An umbrella or a shovel earns its place on about 104 days a year with 1 mm or more.
Environment and Climate Change Canada’s 1991–2020 normals at its Toronto (City) station, 8.1 km east.
A year in Mount Dennis at a glance
Each month’s typical high and low, in °C.
What stands out about Mount Dennis’s climate
Compared with Canadian towns, with its place among towns of 2,500+ in Ontario beside it.
What a year in Mount Dennis feels like
Typical highs and lows by season and by month, from ECCC’s 1991–2020 normals.
Frost on 101 days, 20°C on 124
Frosts fall from November to April; January has the most, about 26. About 14 days a year top 30°C.
Frost days by month
Average days at 0°C or below
Days above 20°C by month
Average days
Rain and melted snow: about 823 mm a year
The most falls in June, the least in March.
Rain and snow by month
Millimetres
About 115 cm of snow a year
From November to April snow is likely; January is the peak, at about 32 cm.
Snowfall by month
Centimetres
Toronto (City) publishes no full year of snowfall, so these figures come from Toronto Pearson (Airport), 11 km away.
Heating a home in Mount Dennis
94% of a year’s heating need falls between October and April. Months averaging under 10°C: November to April.
The count adds up, day by day, how far the mean temperature falls short of 18°C. Homes here need less heating than 90% of Canadian towns.
Living with Mount Dennis’s climate
The averages read for the garden, the outdoors and the coldest and hottest days.
The frost-free stretch runs from about 11 April to about 6 November, some 208 days in a normal year.
Mild days and mild nights together (17–27°C by day, 8°C or more at night) belong to May, Jun, Jul, Aug and Sep.
Parks & trails →Summer brings about 59 days when the humidex passes 30.
Thirty-year normals hide the storms and the extremes: the hazards page has Mount Dennis’s risks.
Flood & hazards →ECCC’s normals location: Toronto (City)
ECCC builds the Toronto (City) normals from 2 stations’ records over 1991–2020, joined where one replaced another.
| Distance from the town | 8.1 km east |
| Station altitude | 113 m |
| Completeness | meets the WMO “3 and 5” rule |
| WMO standard normals | No |
| Snowfall from | Toronto Pearson (Airport), 11 km |
| Coldest reading, 1991–2020 | −25.9°C |
| Hottest reading, 1991–2020 | 38.2°C |
| Next-nearest location | Toronto (Island), 10 km |
How Mount Dennis compares
Compared with 2,611 towns and neighbourhoods of 2,500 or more across Canada; the dots mark the other normals locations in Ontario.
Nearby towns’ climate
Nearby places read from a different ECCC location (places on Mount Dennis’s own would show the same figures).
| Town | July high | January low | Rain & snow |
|---|---|---|---|
| Mount Dennis Toronto (City) | 27.0°C | −6.7°C | 823 mm |
| Rockcliffe-Smythe 1.3 km · Toronto (City) | 27.0°C about the same | −6.7°C about the same | 823 mm |
| Humber Heights-Westmount 2.1 km · Toronto Pearson (Airport) | 27.4°C about the same | −8.9°C 2.2°C colder | 807 mm |
Mount Dennis weather by month
Each month’s normals, 1991–2020: high, low, mean, precipitation and snowfall.
| Month | High | Low | Mean | Rain & snow | Snow |
|---|---|---|---|---|---|
| January | −0.3°C | −6.7°C | −3.5°C | 65 mm | 32 cm |
| February | 0.6°C | −6.0°C | −2.7°C | 54 mm | 28 cm |
| March | 5.1°C | −1.8°C | 1.7°C | 53 mm | 17 cm |
| April | 11.7°C | 3.9°C | 7.8°C | 78 mm | 5 cm |
| May | 18.8°C | 10.0°C | 14.5°C | 76 mm | under 1 cm |
| June | 24.2°C | 15.3°C | 19.8°C | 82 mm | 0 cm |
| July | 27.0°C | 18.1°C | 22.5°C | 77 mm | 0 cm |
| August | 26.1°C | 17.7°C | 21.9°C | 72 mm | 0 cm |
| September | 22.0°C | 13.8°C | 17.9°C | 69 mm | 0 cm |
| October | 14.6°C | 7.7°C | 11.2°C | 69 mm | under 1 cm |
| November | 8.1°C | 2.3°C | 5.2°C | 71 mm | 9 cm |
| December | 2.6°C | −2.7°C | −0.1°C | 58 mm | 24 cm |
| Year | 13.4°C | 6.0°C | 9.7°C | 823 mm | 115 cm |
From year to year, January moves by 2.7°C, more than any month, and June least
Bars run from each month’s record low to its record high since 1991. March spans the most, from −23.1°C (2003) to 25.7°C (1998).
Where Mount Dennis’s numbers come from
Averages over 30 years, not a forecast.
- Normals: the closest ECCC location with twelve months of temperature normals, Toronto (City), 1991–2020.
- Other locations: ECCC blanks a month that fails its completeness rule, so the precipitation or snowfall here comes from the next location with all twelve months.
- 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: hours of sunshine, missing from the 1991–2020 normals, and a height correction: the town has no elevation on file.
Canadian Climate Normals 1991–2020 · ECCC Data Services End-use Licence. Data Source: Environment and Climate Change Canada
Questions about Mount Dennis’s climate
How warm does Mount Dennis get in summer?
Afternoons average 27.0°C in July, the warmest time of year.
How cold does Mount Dennis get in winter?
January nights average −6.7°C, the coldest of the year.
How much rain and snow does Mount Dennis get?
Measured as water, a year brings 823 mm: 82 mm in June, the wettest month, and 53 mm in March, the driest.
Are these figures for Mount Dennis itself?
Almost: ECCC’s Toronto (City) location, which gives these figures, lies a short way outside Mount Dennis.
Data Source: Environment and Climate Change Canada · ECCC Data Services End-use Licence Today’s forecast for Mount Dennis →
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).