Climate and average weather in Yellowknife
In Yellowknife, the summers are mild, fairly dry, and partly cloudy and the winters are frigid, snowy, and mostly cloudy.
Over the course of the year, the temperature in Yellowknife typically varies from -28°C to 21°C, and is rarely below -39°C or above 26°C. July is the hottest month of the year, while January is the coldest.
Based on the travel score, the best time of year to visit Yellowknife for warm-weather activities is from early June to mid August.
- Hottest
- Jul
- 21°
- Coldest
- Jan
- -28°
- Wettest
- Aug
- 46 mm
- Driest
- Feb
- 6 mm
- Rain / yr
- 254 mm
- 61 wet days
- Daylight
- 4.5–19.5 h
- shortest–longest
- Elevation
- 252 m
- 62.5°N
- Clearest
- May
- 58% cloud
Yellowknife is capital and largest city of the Northwest Territories, Canada.
- Air quality
- Excellent
- PM2.5 4 µg/m³ · 2019
- Density
- 149/km²
- people per km²
- Founded
- 1970
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Yellowknife weather by month, at a glance
The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.
Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around early June to mid August.
Temperature through the year
Daily average highs and lows in Yellowknife, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.
The hot season lasts 4.0 months, from May 18 to September 16, with daily high temperatures above 10°C. The hottest month of the year in Yellowknife is July, with an average high of 21°C and low of 13°C.
The cool season lasts 3.4 months, from November 28 to March 11, with daily high temperatures below -14°C. The coldest month of the year in Yellowknife is January, with an average low of -28°C and high of -22°C.
Days typically run about 7°C warmer than nights, with the widest day–night swing (around 10°C) in May.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | -22 | -19 | -12 | -1 | 10 | 18 | 21 | 18 | 11 | 1 | -9 | -18 |
| Avg low (°C) | -28 | -26 | -21 | -11 | 0 | 8 | 13 | 11 | 5 | -3 | -15 | -24 |
| Avg high (°C) | Avg low (°C) | |
|---|---|---|
| Jan | -22 | -28 |
| Feb | -19 | -26 |
| Mar | -12 | -21 |
| Apr | -1 | -11 |
| May | 10 | 0 |
| Jun | 18 | 8 |
| Jul | 21 | 13 |
| Aug | 18 | 11 |
| Sep | 11 | 5 |
| Oct | 1 | -3 |
| Nov | -9 | -15 |
| Dec | -18 | -24 |
How hot and cold Yellowknife really feels
The felt-temperature range through the year — heat index on the day's high (summer humidity), wind chill on the night's low (winter wind). The dashed lines are the plain thermometer; the gap is how much hotter or colder it really feels.
On the coldest nights, wind chill pulls the feels-like down to about -38°C (around January 15), with roughly 247 freezing days a year (feels-like at or below 0°C) — 190 of them bitterly cold — worst in January.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Feels-like high (°C) | -22 | -19 | -12 | -1 | 10 | 18 | 21 | 18 | 11 | 1 | -10 | -18 |
| Air high (°C) | -22 | -19 | -12 | -1 | 10 | 18 | 21 | 18 | 11 | 1 | -9 | -18 |
| Feels-like low (°C) | -38 | -36 | -29 | -17 | -4 | 7 | 13 | 10 | 1 | -8 | -23 | -33 |
| Air low (°C) | -28 | -26 | -21 | -11 | 0 | 8 | 13 | 11 | 5 | -3 | -15 | -24 |
| Feels-like high (°C) | Air high (°C) | Feels-like low (°C) | Air low (°C) | |
|---|---|---|---|---|
| Jan | -22 | -22 | -38 | -28 |
| Feb | -19 | -19 | -36 | -26 |
| Mar | -12 | -12 | -29 | -21 |
| Apr | -1 | -1 | -17 | -11 |
| May | 10 | 10 | -4 | 0 |
| Jun | 18 | 18 | 7 | 8 |
| Jul | 21 | 21 | 13 | 13 |
| Aug | 18 | 18 | 10 | 11 |
| Sep | 11 | 11 | 1 | 5 |
| Oct | 1 | 1 | -8 | -3 |
| Nov | -10 | -9 | -23 | -15 |
| Dec | -18 | -18 | -33 | -24 |
Average hourly temperature in Yellowknife
A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.
Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on July afternoons, near 21°C, and coldest before dawn in January, near -28°C.
Yellowknife weather by month
Every month at a glance. Click a month for its detailed page.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | -22° / -28° | 10 | 3.4 | 4.4 | 5.6 | 0.0 |
| Feb | -19° / -26° | 6 | 2.1 | 2.8 | 8.2 | 0.0 |
| Mar | -12° / -21° | 10 | 3.2 | 4.2 | 11.3 | 0.0 |
| Apr | -1° / -11° | 11 | 3.1 | 2.5 | 14.4 | 0.0 |
| May | 10° / 0° | 19 | 4.6 | 1.4 | 17.4 | 2.5 |
| Jun | 18° / 8° | 25 | 5.3 | 0 | 19.3 | 6.2 |
| Jul | 21° / 13° | 37 | 7.3 | 0 | 18.5 | 6.8 |
| Aug | 18° / 11° | 46 | 9.2 | 0 | 15.8 | 5.7 |
| Sep | 11° / 5° | 40 | 8.2 | 0.5 | 12.6 | 2.5 |
| Oct | 1° / -3° | 24 | 6.4 | 4.3 | 9.5 | 0.0 |
| Nov | -10° / -16° | 15 | 4.6 | 6 | 6.5 | 0.0 |
| Dec | -18° / -24° | 10 | 3.4 | 4.5 | 4.7 | 0.0 |
Chance of rain
How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.
Yellowknife gets about 254 mm of precipitation a year. On a typical day the chance of rain is some rain, but that rises and falls sharply with the seasons.
The wetter season lasts 5.1 months, from around Jun 4 to Nov 4, peaking in August at about 32% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Feb 23.
August is the wettest month by volume, with 46 mm over about 9 wet days; February is the driest, with 6 mm. Some of the cold-season precipitation falls as snow.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain on a day (%) | 11 | 8 | 10 | 11 | 15 | 18 | 23 | 29 | 27 | 21 | 16 | 11 |
| Rain days | 3 | 2 | 3 | 3 | 5 | 5 | 7 | 9 | 8 | 6 | 5 | 3 |
| Rain on a day (%) | Rain days | |
|---|---|---|
| Jan | 11 | 3 |
| Feb | 8 | 2 |
| Mar | 10 | 3 |
| Apr | 11 | 3 |
| May | 15 | 5 |
| Jun | 18 | 5 |
| Jul | 23 | 7 |
| Aug | 29 | 9 |
| Sep | 27 | 8 |
| Oct | 21 | 6 |
| Nov | 16 | 5 |
| Dec | 11 | 3 |
Monthly rainfall
Over a full year, Yellowknife collects about 254 mm of rain across 61 wet days — roughly 21 mm in an average month.
It doesn’t fall evenly. August is the wettest month with 46 mm, while February is the driest at just 6 mm. The three wettest months alone bring about 48% of the year’s total, and some of the cold-season precipitation falls as snow.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rainfall (mm) | 10 | 6 | 10 | 11 | 19 | 25 | 37 | 46 | 40 | 24 | 15 | 10 |
| Rain days | 3 | 2 | 3 | 3 | 5 | 5 | 7 | 9 | 8 | 6 | 5 | 3 |
| Snow days | 4 | 3 | 4 | 3 | 1 | 0 | 0 | 0 | 1 | 4 | 6 | 5 |
| Rainfall (mm) | Rain days | Snow days | |
|---|---|---|---|
| Jan | 10 | 3 | 4 |
| Feb | 6 | 2 | 3 |
| Mar | 10 | 3 | 4 |
| Apr | 11 | 3 | 3 |
| May | 19 | 5 | 1 |
| Jun | 25 | 5 | 0 |
| Jul | 37 | 7 | 0 |
| Aug | 46 | 9 | 0 |
| Sep | 40 | 8 | 1 |
| Oct | 24 | 6 | 4 |
| Nov | 15 | 5 | 6 |
| Dec | 10 | 3 | 5 |
Snow in Yellowknife
Average snowy days through the year, the snow-season span, and estimated snowfall — for ski trips and the perennial 'will there be snow at Christmas?' question.
Yellowknife averages about 31 snowy days a year. Snow season runs roughly Sep 17 to May 28 — about 8.4 months.
November is snowiest, with roughly 6 days of snow and an estimated 21 cm of snowfall. Over the year that adds up to an estimated 109 cm of snow.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Snow days | 4 | 3 | 4 | 3 | 1 | 0 | 0 | 0 | 1 | 4 | 6 | 5 |
| Snowfall (cm) | 13 | 10 | 14 | 11 | 5 | 0 | 0 | 0 | 2 | 17 | 21 | 16 |
| Snow days | Snowfall (cm) | |
|---|---|---|
| Jan | 4 | 13 |
| Feb | 3 | 10 |
| Mar | 4 | 14 |
| Apr | 3 | 11 |
| May | 1 | 5 |
| Jun | 0 | 0 |
| Jul | 0 | 0 |
| Aug | 0 | 0 |
| Sep | 1 | 2 |
| Oct | 4 | 17 |
| Nov | 6 | 21 |
| Dec | 5 | 16 |
Clouds and sunshine
How often the daytime sky is clear, partly cloudy or overcast.
In Yellowknife, the average share of the sky covered by clouds shows significant seasonal variation over the course of the year.
The clearer part of the year begins around March 24 and lasts for 5.0 months, ending around August 21. The clearest month is May, when the sky is clear, mostly clear, or partly cloudy 48% of the time on average.
The cloudier part of the year begins around August 22 and lasts for 5.4 months, ending around January 31. The cloudiest month is October, when it is overcast or mostly cloudy 86% of the time.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 27 | 33 | 33 | 40 | 48 | 46 | 45 | 37 | 26 | 14 | 16 | 22 |
| Cloudier (%) | 73 | 67 | 67 | 60 | 52 | 54 | 55 | 63 | 74 | 86 | 84 | 78 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| Jan | 27 | 73 |
| Feb | 33 | 67 |
| Mar | 33 | 67 |
| Apr | 40 | 60 |
| May | 48 | 52 |
| Jun | 46 | 54 |
| Jul | 45 | 55 |
| Aug | 37 | 63 |
| Sep | 26 | 74 |
| Oct | 14 | 86 |
| Nov | 16 | 84 |
| Dec | 22 | 78 |
Daylight, sunrise and sunset
Hours of daylight through the year, with sunrise and sunset times.
The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. The longest day, around June 18, brings about 19 h 30 min of light; the shortest, around December 18, only 4 h 30 min — a swing of roughly 15 hours.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 5.6 | 8.2 | 11.3 | 14.4 | 17.4 | 19.3 | 18.5 | 15.8 | 12.6 | 9.5 | 6.5 | 4.7 |
| Sunrise (AM) | 10:00 | 8:44 | 7:10 | 5:24 | 3:52 | 2:55 | 3:26 | 4:49 | 6:14 | 7:37 | 9:09 | 10:17 |
| Sunset (PM) | 3:33 | 5:01 | 6:25 | 7:51 | 9:16 | 10:20 | 10:00 | 8:35 | 6:50 | 5:08 | 3:37 | 2:51 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| Jan | 5.6 | 10:00 | 3:33 |
| Feb | 8.2 | 8:44 | 5:01 |
| Mar | 11.3 | 7:10 | 6:25 |
| Apr | 14.4 | 5:24 | 7:51 |
| May | 17.4 | 3:52 | 9:16 |
| Jun | 19.3 | 2:55 | 10:20 |
| Jul | 18.5 | 3:26 | 10:00 |
| Aug | 15.8 | 4:49 | 8:35 |
| Sep | 12.6 | 6:14 | 6:50 |
| Oct | 9.5 | 7:37 | 5:08 |
| Nov | 6.5 | 9:09 | 3:37 |
| Dec | 4.7 | 10:17 | 2:51 |
Sunny days
How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.
Yellowknife averages about 6 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 2 and 11 days.
The sunnier stretch runs 6.6 months, from around Jan 29 to Aug 17. The sunniest month is May, with roughly 11 sunny days (mixed).
The greyest month is October, down near 2 sunny days — about 80% fewer than the May peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sunny days | 5 | 7 | 7 | 9 | 11 | 9 | 8 | 7 | 4 | 2 | 2 | 4 |
| Sky | Gloomy | Gloomy | Gloomy | Mixed | Mixed | Mixed | Gloomy | Gloomy | Gloomy | Gloomy | Gloomy | Gloomy |
| Sunny days | Sky | |
|---|---|---|
| Jan | 5 | Gloomy |
| Feb | 7 | Gloomy |
| Mar | 7 | Gloomy |
| Apr | 9 | Mixed |
| May | 11 | Mixed |
| Jun | 9 | Mixed |
| Jul | 8 | Gloomy |
| Aug | 7 | Gloomy |
| Sep | 4 | Gloomy |
| Oct | 2 | Gloomy |
| Nov | 2 | Gloomy |
| Dec | 4 | Gloomy |
Humidity comfort
Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.
Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.
In Yellowknife, the air stays dry or comfortable essentially all year. Even in July, the muggiest month, it feels humid or worse only about 0% of the time — humidity is not something you need to plan around here.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 100 | 100 | 100 | 100 | 100 | 99 | 89 | 91 | 100 | 100 | 100 | 100 |
| Comfortable (%) | 0 | 0 | 0 | 0 | 0 | 1 | 10 | 9 | 0 | 0 | 0 | 0 |
| Dry (%) | Comfortable (%) | |
|---|---|---|
| Jan | 100 | 0 |
| Feb | 100 | 0 |
| Mar | 100 | 0 |
| Apr | 100 | 0 |
| May | 100 | 0 |
| Jun | 99 | 1 |
| Jul | 89 | 10 |
| Aug | 91 | 9 |
| Sep | 100 | 0 |
| Oct | 100 | 0 |
| Nov | 100 | 0 |
| Dec | 100 | 0 |
Wind
Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.
This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.
Across the year, average wind speed in Yellowknife is typically light breeze, near 13 km/h, and varies little with the seasons.
The windier part of the year lasts 3.6 months, from around Aug 7 to Nov 25. The windiest month is September, averaging about 14 km/h (light breeze).
The calmer part of the year runs from around Nov 26 to Mar 24, with February the calmest month at about 11 km/h.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (km/h) | 12 | 11 | 12 | 13 | 13 | 12 | 12 | 13 | 14 | 14 | 13 | 12 |
| Feels | calm | calm | light breeze | light breeze | light breeze | light breeze | calm | light breeze | light breeze | light breeze | light breeze | light breeze |
| Wind speed (km/h) | Feels | |
|---|---|---|
| Jan | 12 | calm |
| Feb | 11 | calm |
| Mar | 12 | light breeze |
| Apr | 13 | light breeze |
| May | 13 | light breeze |
| Jun | 12 | light breeze |
| Jul | 12 | calm |
| Aug | 13 | light breeze |
| Sep | 14 | light breeze |
| Oct | 14 | light breeze |
| Nov | 13 | light breeze |
| Dec | 12 | light breeze |
Best time to visit Yellowknife
To characterize how pleasant the weather is in Yellowknife throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.
Around mid June, Yellowknife is still near the start of its best-weather window — great conditions with the peak-season crowds not yet at full swing.
Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.
The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best time of year to visit Yellowknife for general outdoor tourist activities is from early June to mid August, with a peak score in the last week of July.
The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Travel score (0–10) | 0.0 | 0.0 | 0.0 | 0.0 | 2.5 | 6.1 | 6.8 | 5.6 | 2.5 | 0.1 | 0.0 | 0.0 |
| Rating | poor | poor | poor | poor | poor | good | good | good | poor | poor | poor | poor |
| Travel score (0–10) | Rating | |
|---|---|---|
| Jan | 0.0 | poor |
| Feb | 0.0 | poor |
| Mar | 0.0 | poor |
| Apr | 0.0 | poor |
| May | 2.5 | poor |
| Jun | 6.1 | good |
| Jul | 6.8 | good |
| Aug | 5.6 | good |
| Sep | 2.5 | poor |
| Oct | 0.1 | poor |
| Nov | 0.0 | poor |
| Dec | 0.0 | poor |
The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best time of year to visit Yellowknife for hot-weather activities is from early July to early August, with a peak score in the last week of July.
The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).
What to pack for Yellowknife, by month
Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.
For a warm-season trip around July (highs near 21°C), the essentials are sun protection. In the cold season around January (highs near -22°C), pack a warm layer and a heavy coat.
In July, Yellowknife sees daytime highs around 21°C and nights near 13°C. Worth packing: sun protection. About 7 days see rain.
UV index (midday) in Yellowknife by month
Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.
Under clear skies, the midday UV index in Yellowknife peaks around June 15 at about 4 (moderate) — a little sun protection helps at midday. It bottoms out near January 1 at about 0 (low).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 4 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 0 | 1 | 1 | 3 | 4 | 4 | 4 | 3 | 2 | 1 | 0 | 0 |
| Level | Low | Low | Low | Moderate | Moderate | Moderate | Moderate | Moderate | Low | Low | Low | Low |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 0 | Low |
| Feb | 1 | Low |
| Mar | 1 | Low |
| Apr | 3 | Moderate |
| May | 4 | Moderate |
| Jun | 4 | Moderate |
| Jul | 4 | Moderate |
| Aug | 3 | Moderate |
| Sep | 2 | Low |
| Oct | 1 | Low |
| Nov | 0 | Low |
| Dec | 0 | Low |
Average hourly UV index in Yellowknife
Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.
The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.
UV falls off far faster than brightness as the sun drops, so even in June the burn window is concentrated in the middle of the day: about 5.5 hours a day reach index 3 (protection recommended). Mornings and late afternoons stay comparatively gentle year round.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV ≥ 3 (h/day) | 0 | 0 | 0 | 0 | 5 | 5.5 | 5 | 2 | 0 | 0 | 0 | 0 |
| UV ≥ 6 (h/day) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| UV ≥ 3 (h/day) | UV ≥ 6 (h/day) | |
|---|---|---|
| Jan | 0 | 0 |
| Feb | 0 | 0 |
| Mar | 0 | 0 |
| Apr | 0 | 0 |
| May | 5 | 0 |
| Jun | 5.5 | 0 |
| Jul | 5 | 0 |
| Aug | 2 | 0 |
| Sep | 0 | 0 |
| Oct | 0 | 0 |
| Nov | 0 | 0 |
| Dec | 0 | 0 |
Air quality in Yellowknife by month
Average fine-particle pollution (PM2.5) through the year — so you can see which months the air is worst, not just the yearly average.
Air quality in Yellowknife is worst in August — around 22 µg/m³ PM2.5 (moderate), about 224.0× the cleanest month (January, 0 µg/m³).
Seasonal pattern from CAMS reanalysis, scaled to Yellowknife's WHO annual average of 4 µg/m³.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 0 | 0 | 1 | 2 | 2 | 4 | 13 | 22 | 3 | 0 | 0 | 0 |
| Level | Good | Good | Good | Good | Good | Good | Moderate | Moderate | Good | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 0 | Good |
| Feb | 0 | Good |
| Mar | 1 | Good |
| Apr | 2 | Good |
| May | 2 | Good |
| Jun | 4 | Good |
| Jul | 13 | Moderate |
| Aug | 22 | Moderate |
| Sep | 3 | Good |
| Oct | 0 | Good |
| Nov | 0 | Good |
| Dec | 0 | Good |
Growing season
The growing season in Yellowknife typically lasts about 143 days, from around May 16 to October 5 — the span where a frost-free day is more likely than not. It is reliably frost-free from June 3 to September 16.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Frost-free chance (%) | 0 | 0 | 1 | 8 | 52 | 98 | 100 | 100 | 87 | 27 | 2 | 0 |
| Frost nights | 31 | 28 | 31 | 30 | 31 | 1 | 0 | 0 | 14 | 31 | 30 | 31 |
| Frost-free chance (%) | Frost nights | |
|---|---|---|
| Jan | 0 | 31 |
| Feb | 0 | 28 |
| Mar | 1 | 31 |
| Apr | 8 | 30 |
| May | 52 | 31 |
| Jun | 98 | 1 |
| Jul | 100 | 0 |
| Aug | 100 | 0 |
| Sep | 87 | 14 |
| Oct | 27 | 31 |
| Nov | 2 | 30 |
| Dec | 0 | 31 |
Growing degree days
Growing degree days tally heat above 10°C: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Yellowknife banks about 430 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around July.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Growing degree days (°C·days) | 0 | 0 | 0 | 0 | 0 | 91 | 205 | 131 | 3 | 0 | 0 | 0 |
| Growing degree days (°C·days) | |
|---|---|
| Jan | 0 |
| Feb | 0 |
| Mar | 0 |
| Apr | 0 |
| May | 0 |
| Jun | 91 |
| Jul | 205 |
| Aug | 131 |
| Sep | 3 |
| Oct | 0 |
| Nov | 0 |
| Dec | 0 |
Solar energy
Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.
Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.
Yellowknife receives about 2.9 kWh/m² a day of solar energy on average — moderate — with a clear seasonal swing between 0.1 and 6.4 kWh/m².
The brighter stretch of the year lasts 5.6 months, from around Mar 20 to Sep 5. The brightest month is June, averaging about 6.3 kWh/m² (intense).
The dimmest month is December, down near 0.1 kWh/m² — roughly 98% less than the June peak.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 0.3 | 1.1 | 2.7 | 4.7 | 6.0 | 6.4 | 5.7 | 4.1 | 2.4 | 1.0 | 0.4 | 0.1 |
| Level | Dim | Dim | Moderate | Bright | Bright | Intense | Bright | Bright | Moderate | Dim | Dim | Dim |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| Jan | 0.3 | Dim |
| Feb | 1.1 | Dim |
| Mar | 2.7 | Moderate |
| Apr | 4.7 | Bright |
| May | 6.0 | Bright |
| Jun | 6.4 | Intense |
| Jul | 5.7 | Bright |
| Aug | 4.1 | Bright |
| Sep | 2.4 | Moderate |
| Oct | 1.0 | Dim |
| Nov | 0.4 | Dim |
| Dec | 0.1 | Dim |
Where is Yellowknife?
Yellowknife sits at 62.5°N, 114.4°W, 252 m above sea level, in Canada. The nearest listed city is Fort McMurray, 659 km away.
What Yellowknife looks like
Topography around Yellowknife
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Yellowknife.
Within 3 km, the terrain around Yellowknife has only modest variations in elevation — a maximum elevation change of 56 m around an average of 180 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 97 m; within 80 km, only modest variations in elevation — a maximum elevation change of 220 m.
The land around Yellowknife is covered by trees (43%) and water (31%) within 3 km, trees (60%) and water (29%) within 16 km, and trees (50%) and water (40%) within 80 km.
Canada travel facts
- Travel advisory
- Level 1
- Exercise Normal Precautions
- Power plugs
- Type A / B
- 120 V · 60 Hz
- Prices
- ≈ 83% of US
- price level, 2025
- GDP per capita
- $55,698
- 2025
- Happiness
- 6.7 / 10
- World Happiness, 2025
- Safe drinking water
- 97%
- of population, 2024
- Homicide rate
- 2
- per 100k, 2023
- Road deaths
- 5.3
- per 100k/yr, 2019
- Income group
- High
- World Bank
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Yellowknife (62.4541°, -114.3725°, elevation 252 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).