Photo: Raysonho @ Open Grid Scheduler / Grid Engine · CC0Summer afternoons in Markham are warmer than in 91% of Canadian towns
Midwinter brings lows of about −10.1°C. Frost is rarer than in 70% of Canadian towns: about 145 nights a year drop below freezing. Of all months, June brings the most precipitation and February the least. Expect about 145 frosty starts a year, days when the air falls to freezing.
Figures: ECCC’s 1991–2020 normals at Toronto Buttonville (Airport) (5.6 km west).
A year in Markham at a glance
Each month’s typical high and low, in °C.
What stands out about Markham’s climate
Compared with Canadian towns, with its place among towns of 2,500+ in Ontario beside it.
What a year in Markham feels like
Each season’s and each month’s usual high and low, 1991–2020.
About 145 frosts and 126 warm days a year
Frost comes from October to May; in January almost every night freezes. Some 6 nights a year drop under −20°C.
Frost days by month
Average days at 0°C or below
Days above 20°C by month
Average days
About 862 mm of rain and snow a year
On about 113 days a year, 1 mm or more falls.
Rain and snow by month
Millimetres
Rain alone by month
Millimetres
146 cm of snow in a typical year
From November to April snow is likely; January is the peak, at about 40 cm.
Snowfall by month
Centimetres
Snow on the ground by month
Centimetres at month’s end
Heating a home in Markham
93% of a year’s heating need falls between October and April. Months averaging under 10°C: October to April.
Each day the mean sits under 18°C adds its shortfall; a year’s total is its heating degree days. A house here needs less heating than 74% of Canadian towns.
Living with Markham’s climate
What the normals mean for a garden, a day outside and the depth of winter.
About 161 days a year pass without frost, from an average last frost of 3 May to a first of 13 October.
Mild days and mild nights together (17–27°C by day, 8°C or more at night) belong to Jun, Aug and Sep.
Parks & trails →Winter brings about 22 days with a wind chill below −20.
Roughly 55 days a year feel hotter than 30 once humidity is counted.
For blizzards, floods and wildfire, turn to Markham’s hazards page.
Flood & hazards →ECCC’s normals location: Toronto Buttonville (Airport)
Behind the 1991–2020 normals for Toronto Buttonville (Airport) are 3 stations, which ECCC combines into one record.
| Distance from the town | 5.6 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), 23 km |
How Markham 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 Markham’s own would show the same figures). No closer places have figures: these lie 16–30 km from Markham.
| Town | July high | January low | Rain & snow |
|---|---|---|---|
| Markham Toronto Buttonville (Airport) | 27.3°C | −10.1°C | 862 mm |
| Pickering 16 km · Oshawa | 25.7°C 1.6°C cooler | −8.9°C 1.2°C milder | 906 mm |
| Toronto 18 km · Toronto (City) | 27.0°C about the same | −6.7°C 3.4°C milder | 823 mm |
| East Gwillimbury 30 km · Udora | 26.3°C 1.0°C cooler | −11.7°C 1.6°C colder | 883 mm |
Markham weather by month
Each month’s normals, 1991–2020: high, low, mean, precipitation and 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 March here can run from −25.6°C to 26.3°C
Bars run from each month’s record low to its record high over 1991–2020; January is the month whose average wanders most from year to year (±3.1°C around −6.0°C), June the one that wanders least (±1.2°C).
Where Markham’s numbers come from
Averages over 30 years, not a forecast.
- Normals: Environment and Climate Change Canada’s 1991–2020 normals, Toronto Buttonville (Airport): the nearest of its locations with every month’s temperatures.
- Comparisons: Canadian towns and neighbourhoods of at least 2,500, each placed by its nearest location (city totals and reserves excluded).
- 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 Markham’s climate
How warm does Markham get in summer?
Midsummer means July, with afternoons near 27.3°C on a typical day.
How cold does Markham get in winter?
Midwinter means January, when a typical night reaches −10.1°C.
How much rain and snow does Markham get?
862 mm a year counting snow as water. The wettest month is June (87 mm); the driest, February (51 mm).
How long does snow stay on the ground?
Snow cover of 1 cm or more lasts about 76 days in a typical year.
Are these figures for Markham itself?
Yes: ECCC’s 1991–2020 normals for Toronto Buttonville (Airport), which is in Markham.
Data Source: Environment and Climate Change Canada · ECCC Data Services End-use Licence Today’s forecast for Markham →
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).