Photo: sfbnurse https://www.flickr.com/people/sfbnurse/ · CC BY 2.0Fort Simpson has some of the coldest winter nights among Canadian towns
Expect July afternoons of about 23.8°C. By precipitation alone, it ranks drier than 97% of Canadian towns. The year is lopsided: August gets about 4.0 times what March does. Heating does most of its work from September to May, in months below 10°C on average.
Measured at Fort Simpson, 6.2 km south-east: ECCC’s normals for 1991–2020.
A year in Fort Simpson at a glance
Each month’s typical high and low, in °C.
What stands out about Fort Simpson’s climate
Compared with Canadian towns, with its place among towns of 2,500+ in the Northwest Territories beside it.
What a year in Fort Simpson feels like
Typical highs and lows by season and by month, from ECCC’s 1991–2020 normals.
221 frost days and 78 days above 20°C a year
Frost comes from September to May; in January almost every night freezes. Deep cold, under −20°C, comes on about 97 nights a year.
Frost days by month
Average days at 0°C or below
Days above 20°C by month
Average days
371 mm of precipitation in a typical year
The wettest of 4 towns of 2,500+ in the Northwest Territories. On about 74 days a year, 1 mm or more falls.
Rain and snow by month
Millimetres
Rain alone by month
Millimetres
195 cm of snow in a typical year
Snow falls from September to May, most of all in November (about 36 cm). The snowiest of 3 towns of 2,500+ in the Northwest Territories.
Snowfall by month
Centimetres
Snow on the ground by month
Centimetres at month’s end
Heating a home in Fort Simpson
89% of a year’s heating need falls between October and April. Months averaging under 10°C: September to May.
Warm days count for nothing; each colder day adds how far its mean sits below 18°C. That means homes here need more heating than almost every Canadian town.
Living with Fort Simpson’s climate
What the normals mean for a garden, a day outside and the depth of winter.
For long days outdoors, Jun, Jul and Aug bring highs of 17–27°C and lows of 8°C or more.
Parks & trails →Winter brings about 121 days with a wind chill below −20.
Humid summer days, the humidex above 30, number about 9 a year.
For blizzards, floods and wildfire, turn to Fort Simpson’s hazards page.
Flood & hazards →ECCC’s normals location: Fort Simpson
Fort Simpson is a composite: ECCC joins 3 stations’ readings to make its 1991–2020 normals.
| Distance from the town | 6.2 km south-east |
| Station altitude | 169 m |
| Completeness | meets the WMO “3 and 5” rule |
| WMO standard normals | Yes |
| Coldest reading, 1991–2020 | −48.8°C |
| Hottest reading, 1991–2020 | 36.6°C |
| Average wind | 8.2 km/h on average, most often from the north-west |
| Next-nearest location | Fort Providence, 204 km |
How Fort Simpson compares
Against the 2,611 Canadian towns and neighbourhoods of 2,500 or more, each read from its own normals location; the dots are the other locations those towns use in the Northwest Territories.
Fort Simpson weather by month
Each month’s normals, 1991–2020: high, low, mean, precipitation and snowfall.
| Month | High | Low | Mean | Rain & snow | Snow |
|---|---|---|---|---|---|
| January | −19.3°C | −27.8°C | −23.6°C | 18 mm | 31 cm |
| February | −14.2°C | −24.7°C | −19.5°C | 16 mm | 26 cm |
| March | −6.0°C | −19.1°C | −12.5°C | 15 mm | 20 cm |
| April | 5.7°C | −6.7°C | −0.5°C | 16 mm | 18 cm |
| May | 15.9°C | 2.8°C | 9.3°C | 30 mm | 8 cm |
| June | 21.9°C | 9.2°C | 15.6°C | 56 mm | 1 cm |
| July | 23.8°C | 11.5°C | 17.7°C | 57 mm | 0 cm |
| August | 21.1°C | 9.0°C | 15.1°C | 60 mm | 0 cm |
| September | 14.1°C | 2.9°C | 8.5°C | 32 mm | 4 cm |
| October | 2.4°C | −5.1°C | −1.4°C | 32 mm | 24 cm |
| November | −10.6°C | −18.4°C | −14.5°C | 22 mm | 36 cm |
| December | −17.5°C | −25.7°C | −21.6°C | 17 mm | 28 cm |
| Year | 3.1°C | −7.7°C | −2.3°C | 371 mm | 195 cm |
Two years in three, March’s average lands within 3.8°C of normal, against the steadier July
December has the widest record range, −46.7°C in 2000 to 14.5°C in 1999; the tick on each bar is the month’s normal.
Where Fort Simpson’s numbers come from
Averages over 30 years, not a forecast.
- Normals: ECCC’s 1991–2020 Canadian Climate Normals for Fort Simpson, 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, 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 Fort Simpson’s climate
How warm does Fort Simpson get in summer?
Peak warmth comes in July, at about 23.8°C by mid-afternoon.
How cold does Fort Simpson get in winter?
The year’s coldest nights belong to January, at about −27.8°C.
How much rain and snow does Fort Simpson get?
Over twelve months, rain and melted snow come to 371 mm; the range runs from 15 mm in March to 60 mm in August.
How long does snow stay on the ground?
Roughly 193 days a year start with snow cover of 1 cm or more.
Are these figures for Fort Simpson itself?
Yes, from ECCC’s station within Fort Simpson’s boundary.
Data Source: Environment and Climate Change Canada · ECCC Data Services End-use Licence Today’s forecast for Fort Simpson →
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).