Mount Joy has warmer summer afternoons than 91% of Canadian towns
Deep winter brings January lows near −10.1°C. Temperatures cover 37°C across the year, low to high. Frosty nights are scarcer than in 70% of Canadian towns. Ice scrapers and block heaters earn their keep on roughly 145 days a year at 0°C or below.
Borrowed figures: Mount Joy has no normals station, so these come from Toronto Buttonville (Airport), 8.9 km west.
A year in Mount Joy at a glance
Each month’s typical high and low, in °C.
What stands out about Mount Joy’s climate
Compared with Canadian towns, with its place among towns of 2,500+ in Ontario beside it.
What a year in Mount Joy feels like
Each season’s and each month’s usual high and low, 1991–2020.
Frost on 145 days, 20°C on 126
Frost comes from October to May; in January almost every night freezes. Deep cold, under −20°C, comes on about 6 nights a year.
Frost days by month
Average days at 0°C or below
Days above 20°C by month
Average days
862 mm of precipitation in a typical year
June is the wettest month and February the driest. Some 113 days a year see 1 mm of rain or snow or more.
Rain and snow by month
Millimetres
Rain alone by month
Millimetres
Snowfall: about 146 cm in a normal year
Expect snow from November to April, with about 40 cm in January, the snowiest month.
Snowfall by month
Centimetres
Snow on the ground by month
Centimetres at month’s end
Heating a home in Mount Joy
93% of a year’s heating need falls between October and April. Months averaging under 10°C: October to April.
Heating degree days total each day’s gap between its mean temperature and 18°C. In heating terms, homes need less heating than 74% of Canadian towns.
Living with Mount Joy’s climate
What the normals mean for a garden, a day outside and the depth of winter.
Between the last frost, near 3 May, and the first, near 13 October, lie about 161 frost-free days.
Afternoons of 17–27°C and nights of at least 8°C arrive in Jun, Aug and Sep.
Parks & trails →Expect around 22 days a year when the wind chill sinks below −20.
The humidex tops 30 on about 55 days a year: muggy days to plan around.
Storms, floods and heat waves sit outside these normals; Mount Joy’s hazards page covers them.
Flood & hazards →ECCC’s normals location: Toronto Buttonville (Airport)
Toronto Buttonville (Airport) is a composite: ECCC joins 3 stations’ readings to make its 1991–2020 normals.
| Distance from the town | 8.9 km west |
| Station altitude | 198 m |
| Completeness | meets the WMO “3 and 5” rule |
| WMO standard normals | No |
| Coldest reading, 1991–2020 | −35.2°C |
| Hottest reading, 1991–2020 | 37.8°C |
| Average wind | 12.2 km/h on average, most often from the north |
| Next-nearest location | Toronto (City), 27 km |
How Mount Joy 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
Places around Mount Joy whose figures come from another normals location. Mount Joy has few close neighbours with figures, so the list reaches 14–26 km out.
| Town | July high | January low | Rain & snow |
|---|---|---|---|
| Mount Joy Toronto Buttonville (Airport) | 27.3°C | −10.1°C | 862 mm |
| Pickering 14 km · Oshawa | 25.7°C 1.6°C cooler | −8.9°C 1.2°C milder | 906 mm |
| Toronto 22 km · Toronto (City) | 27.0°C about the same | −6.7°C 3.4°C milder | 823 mm |
| Uxbridge 26 km · Udora | 26.3°C 1.0°C cooler | −11.7°C 1.6°C colder | 883 mm |
Mount Joy 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 | −1.7°C | −10.1°C | −6.0°C | 64 mm | 40 cm |
| February | −1.0°C | −10.1°C | −5.6°C | 51 mm | 34 cm |
| March | 4.6°C | −5.0°C | −0.2°C | 52 mm | 20 cm |
| April | 11.8°C | 1.2°C | 6.5°C | 79 mm | 7 cm |
| May | 19.3°C | 7.4°C | 13.4°C | 80 mm | under 1 cm |
| June | 24.6°C | 13.0°C | 18.8°C | 87 mm | 0 cm |
| July | 27.3°C | 15.6°C | 21.5°C | 85 mm | 0 cm |
| August | 26.3°C | 14.8°C | 20.6°C | 72 mm | 0 cm |
| September | 21.9°C | 10.4°C | 16.2°C | 83 mm | 0 cm |
| October | 14.3°C | 4.3°C | 9.4°C | 71 mm | 1 cm |
| November | 7.4°C | −0.8°C | 3.3°C | 77 mm | 12 cm |
| December | 1.5°C | −5.8°C | −2.2°C | 63 mm | 33 cm |
| Year | 13.0°C | 2.9°C | 8.0°C | 862 mm | 146 cm |
A January here can run warm or cold, its average moving by about 3.1°C; the steadiest month is June
March has the widest record range, −25.6°C in 2003 to 26.3°C in 2012; the tick on each bar is the month’s normal.
Where Mount Joy’s numbers come from
Averages over 30 years, not a forecast.
- Normals: ECCC’s 1991–2020 Canadian Climate Normals for Toronto Buttonville (Airport), the nearest location with a full year of temperatures.
- Comparisons: Canada’s towns and neighbourhoods of 2,500+ (no city totals, no reserves), each through its own nearest location.
- Not on this page: sunshine, absent from every 1991–2020 location, and an altitude correction, for want of the town’s own elevation.
Canadian Climate Normals 1991–2020 · ECCC Data Services End-use Licence. Data Source: Environment and Climate Change Canada
Questions about Mount Joy’s climate
How warm does Mount Joy get in summer?
The year’s warmest days come in July, with highs averaging 27.3°C.
How cold does Mount Joy get in winter?
At its coldest, in January, the normal low is −10.1°C.
How much rain and snow does Mount Joy get?
Precipitation totals 862 mm a year, with June the wettest month (87 mm) and February the driest (51 mm).
How long does snow stay on the ground?
Expect snow on the ground, at least 1 cm, for about 76 days a year.
Are these figures for Mount Joy itself?
No, they come from Toronto Buttonville (Airport); ECCC keeps no 1991–2020 normals in Mount Joy itself.
Data Source: Environment and Climate Change Canada · ECCC Data Services End-use Licence Today’s forecast for Mount Joy →
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).