Professors Lake has warmer summer afternoons than 95% of Canadian towns
On a normal January night the air cools to about −8.9°C. The seasons are far apart: from a winter night to a summer afternoon the average spans 36°C. Only about 131 nights a year bring a frost, fewer than in 82% of Canadian towns. An umbrella or a shovel earns its place on about 106 days a year with 1 mm or more.
The nearest ECCC normals location to Professors Lake is Toronto Pearson (Airport), 11 km south-east, and every figure on this page is its.
A year in Professors Lake at a glance
Each month’s typical high and low, in °C.
What stands out about Professors Lake’s climate
Compared with Canadian towns, with its place among towns of 2,500+ in Ontario beside it.
What a year in Professors Lake feels like
Seasons and months as ECCC’s 1991–2020 normals give them: a typical day’s high and low.
131 frost days and 125 days above 20°C a year
Frost comes from October to April; in January almost every night freezes. Some 17 days a year climb past 30°C.
Frost days by month
Average days at 0°C or below
Days above 20°C by month
Average days
807 mm of precipitation in a typical year
June is the wettest month and February the driest.
Rain and snow by month
Millimetres
Rain alone 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
Snow on the ground by month
Centimetres at month’s end
Heating a home in Professors Lake
93% of a year’s heating need falls between October and April. Months averaging under 10°C: November to April.
Think of it as a year’s worth of daily shortfalls below 18°C, added up. Over a year, a home here needs less heating than 83% of Canadian towns.
Living with Professors Lake’s climate
What the normals mean for a garden, a day outside and the depth of winter.
Count on about 174 frost-free days: the last frost averages 27 April, the first 20 October.
Mild days and mild nights together (17–27°C by day, 8°C or more at night) belong to May, Jun, Aug and Sep.
Parks & trails →About 21 days a year bring a wind chill under −20, when bare skin chills fast.
Summer brings about 56 days when the humidex passes 30.
Ice storms, floods and heat waves are risks, not averages: they are on Professors Lake’s hazards page.
Flood & hazards →ECCC’s normals location: Toronto Pearson (Airport)
ECCC builds the Toronto Pearson (Airport) normals from 2 stations’ records over 1991–2020, joined where one replaced another.
| Distance from the town | 11 km south-east |
| Station altitude | 173 m |
| Completeness | at least 25 years |
| WMO standard normals | No |
| Coldest reading, 1991–2020 | −31.0°C |
| Hottest reading, 1991–2020 | 37.9°C |
| Average wind | 15.7 km/h on average, most often from the west |
| Next-nearest location | Toronto (City), 28 km |
How Professors Lake 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
The nearest places on a normals location of their own: those that share Professors Lake’s would only repeat its figures. No closer places have figures: these lie 19–28 km from Professors Lake.
| Town | July high | January low | Rain & snow |
|---|---|---|---|
| Professors Lake Toronto Pearson (Airport) | 27.4°C | −8.9°C | 807 mm |
| Vaughan 19 km · Toronto Buttonville (Airport) | 27.3°C about the same | −10.1°C 1.2°C colder | 862 mm |
| Toronto 28 km · Toronto (City) | 27.0°C about the same | −6.7°C 2.2°C milder | 823 mm |
| Erin 28 km · Elora | 25.4°C 2.0°C cooler | −10.7°C 1.8°C colder | 807 mm |
Professors Lake 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 | −1.2°C | −8.9°C | −5.0°C | 62 mm | 32 cm |
| February | −0.3°C | −8.5°C | −4.4°C | 50 mm | 28 cm |
| March | 5.0°C | −3.8°C | 0.6°C | 51 mm | 17 cm |
| April | 12.0°C | 1.9°C | 7.0°C | 77 mm | 5 cm |
| May | 19.2°C | 8.2°C | 13.7°C | 78 mm | under 1 cm |
| June | 24.5°C | 13.9°C | 19.2°C | 81 mm | 0 cm |
| July | 27.4°C | 16.6°C | 22.1°C | 74 mm | 0 cm |
| August | 26.3°C | 15.8°C | 21.1°C | 69 mm | 0 cm |
| September | 22.3°C | 11.6°C | 16.9°C | 69 mm | 0 cm |
| October | 14.6°C | 5.3°C | 10.0°C | 67 mm | under 1 cm |
| November | 7.9°C | 0.2°C | 4.1°C | 72 mm | 9 cm |
| December | 1.9°C | −5.0°C | −1.6°C | 59 mm | 24 cm |
| Year | 13.3°C | 3.9°C | 8.6°C | 807 mm | 115 cm |
From −24.7°C to 26.0°C: March’s coldest and warmest days since 1991
The month to count on least is January: one year in three its average strays more than 3.0°C from −5.0°C. June moves least, typically by 1.3°C.
Where Professors Lake’s numbers come from
Averages over 30 years, not a forecast.
- Normals: ECCC’s normals for Toronto Pearson (Airport), 1991–2020, chosen as the nearest location with a full temperature record.
- 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: a sunshine figure (ECCC published none for 1991–2020) and any lapse-rate correction for height, as the town has no elevation here.
Canadian Climate Normals 1991–2020 · ECCC Data Services End-use Licence. Data Source: Environment and Climate Change Canada
Questions about Professors Lake’s climate
How warm does Professors Lake get in summer?
On a normal day in July the thermometer climbs to 27.4°C, the warmest of the year.
How cold does Professors Lake get in winter?
Deep winter means January, when nights average −8.9°C.
How much rain and snow does Professors Lake get?
Some 807 mm falls in a year. Most of it comes in June (81 mm), the least in February (50 mm).
How long does snow stay on the ground?
On about 69 days a year the ground keeps at least 1 cm of snow.
Are these figures for Professors Lake itself?
No, they come from Toronto Pearson (Airport); ECCC keeps no 1991–2020 normals in Professors Lake itself.
Data Source: Environment and Climate Change Canada · ECCC Data Services End-use Licence Today’s forecast for Professors Lake →
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).