Photo: Glenlarson~commonswiki · Public domainSlave Lake has some of the coolest summers among Canadian towns
The depth of winter brings overnight lows near −18.2°C. The year is lopsided: July gets about 6.1 times what March does. It is a dry place: less rain and snow fall here than on 94% of Canadian towns. Frost comes on about 202 days a year, so leave time to clear the car.
Environment and Climate Change Canada’s 1991–2020 normals, measured at Slave Lake, 1.3 km north.
A year in Slave Lake at a glance
Each month’s typical high and low, in °C.
What stands out about Slave Lake’s climate
Compared with Canadian towns, with its place among towns of 2,500+ in Alberta beside it.
What a year in Slave Lake feels like
Typical highs and lows by season and by month, from ECCC’s 1991–2020 normals.
202 frost days and 68 days above 20°C a year
From September to May frost is routine, and in December it comes on almost every night. Some 36 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 422 mm of rain and snow a year
Some 85 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 93 cm in a normal year
The snow season runs October to May; January brings the most, about 20 cm.
Snowfall by month
Centimetres
Heating a home in Slave Lake
86% of a year’s heating need falls between October and April. Months averaging under 10°C: October to May.
Warm days count for nothing; each colder day adds how far its mean sits below 18°C. A house here needs more heating than 96% of Canadian towns.
Living with Slave Lake’s climate
Gardening, time outside, winter cold and summer heat, from the 1991–2020 normals.
Tender plants are usually safe from around 26 May until frost returns near 16 September: about 112 days.
Mild days and mild nights together (17–27°C by day, 8°C or more at night) belong to Jun, Jul and Aug.
Parks & trails →About 71 days a year bring a wind chill under −20, when bare skin chills fast.
The air feels heavier than 30 on the humidex for about 6 days a year.
A typical year is calm by definition; Slave Lake’s hazards page covers the exceptions.
Flood & hazards →ECCC’s normals location: Slave Lake
ECCC builds the Slave Lake normals from 5 stations’ records over 1991–2020, joined where one replaced another.
| Distance from the town | 1.3 km north |
| Station altitude | 583 m |
| Completeness | meets the WMO “3 and 5” rule |
| WMO standard normals | No |
| Coldest reading, 1991–2020 | −44.0°C |
| Hottest reading, 1991–2020 | 34.9°C |
| Average wind | 12.5 km/h on average, most often from the east |
| Next-nearest location | Campsie, 128 km |
How Slave 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 Alberta.
Nearby towns’ climate
The nearest places on a normals location of their own: those that share Slave Lake’s would only repeat its figures. The nearest places to Slave Lake with figures are 74–114 km away.
| Town | July high | January low | Rain & snow |
|---|---|---|---|
| Slave Lake | 21.8°C | −18.2°C | 422 mm |
| Swan Hills 74 km · Whitecourt | 22.2°C about the same | −16.0°C 2.2°C milder | 521 mm |
| High Prairie 109 km · Peace River | 22.7°C 0.9°C warmer | −20.1°C 1.9°C colder | 384 mm |
| Athabasca 114 km · Lac la Biche | 23.1°C 1.3°C warmer | −19.1°C 0.9°C colder | 473 mm |
Slave Lake weather by month
Average daily high and low, mean temperature, rain and snow (as water) and snowfall by month, 1991–2020.
| Month | High | Low | Mean | Rain & snow | Snow |
|---|---|---|---|---|---|
| January | −8.3°C | −18.2°C | −13.3°C | 19 mm | 20 cm |
| February | −4.8°C | −16.2°C | −10.5°C | 13 mm | 12 cm |
| March | 0.6°C | −10.8°C | −5.1°C | 13 mm | 12 cm |
| April | 8.5°C | −3.1°C | 2.7°C | 23 mm | 8 cm |
| May | 15.8°C | 3.0°C | 9.4°C | 41 mm | 1 cm |
| June | 19.6°C | 8.3°C | 14.0°C | 75 mm | 0 cm |
| July | 21.8°C | 10.9°C | 16.4°C | 77 mm | 0 cm |
| August | 20.9°C | 9.5°C | 15.2°C | 56 mm | 0 cm |
| September | 15.7°C | 4.4°C | 10.1°C | 42 mm | under 1 cm |
| October | 8.1°C | −1.4°C | 3.3°C | 27 mm | 8 cm |
| November | −1.1°C | −9.6°C | −5.3°C | 19 mm | 16 cm |
| December | −7.2°C | −16.6°C | −11.9°C | 16 mm | 16 cm |
| Year | 7.5°C | −3.3°C | 2.1°C | 422 mm | 93 cm |
A January here can run from −44.0°C to 16.3°C
Two years in three, December’s average falls within 4.2°C of its normal of −11.9°C; June keeps to within 0.8°C.
Where Slave Lake’s numbers come from
Averages over 30 years, not a forecast.
- Normals: 1991–2020 normals for Slave Lake from ECCC’s climate data site, the nearest location with every month of temperature.
- Comparisons: all Canadian places of 2,500 or more except city totals and reserves, each read the same way.
- Not on this page: sunshine, not in ECCC’s 1991–2020 normals, and the effect of the town’s height, for which there is no figure.
Canadian Climate Normals 1991–2020 · ECCC Data Services End-use Licence. Data Source: Environment and Climate Change Canada
Questions about Slave Lake’s climate
How warm does Slave Lake get in summer?
On a normal day in July the thermometer climbs to 21.8°C, the warmest of the year.
How cold does Slave Lake get in winter?
Of all twelve months, January has the coldest nights, about −18.2°C.
How much rain and snow does Slave Lake get?
A normal year brings 422 mm, snow included as water: July is wettest at 77 mm, March driest at 13 mm.
Are these figures for Slave Lake itself?
Yes: ECCC’s normals station is inside Slave Lake itself.
Data Source: Environment and Climate Change Canada · ECCC Data Services End-use Licence Today’s forecast for Slave 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).