SmogRank / Canada / Northwest Territories / Yellowknife

Yellowknife, month by month

Yellowknife has a measured daily mean on 255 days since 19 September 2025. Its worst month was July 2026, at 115 US AQI (41.2 µg/m³), 61st of 2,784 cities on that month's world ranking. Its cleanest was September 2026, at 3 US AQI (0.5 µg/m³).

Every month since 2025

2026too few days for a mean (a year needs 199)186 days measured
Jan12#2,607Feb11#2,856Mar12#2,961Apr14 daysMay8 daysJun6 daysJul115#61Aug53#807Sep3#2,981Oct5#2,721
2025too few days for a mean (a year needs 256)69 days measured
JanFebMarAprMayJunJulAugSep12 daysOct21 daysNov15 daysDec21 days
Each square is a month's mean PM2.5 in US AQI from Yellowknife's measured days, with its place on that month's world ranking under it. A month has a mean once 70% of its days are measured, the rule the monthly rankings use; under that, the square gives the days measured. Each square opens that month's ranking with Yellowknife marked; each year, the year's. A dashed square is the running month, so far.
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

Months without a mean, and why

7 months
MonthWhy
Jun 20266 of 30 days measured; a month needs 21. The others: 24 with under 18 hours of readings or readings that failed our checks.
May 20268 of 31 days measured; a month needs 22. The others: 23 with under 18 hours of readings or readings that failed our checks.
Apr 202614 of 30 days measured; a month needs 21. The others: 16 with under 18 hours of readings or readings that failed our checks.
Dec 202521 of 31 days measured; a month needs 22. The others: 10 with under 18 hours of readings or readings that failed our checks.
Nov 202515 of 30 days measured; a month needs 21. The others: 15 with under 18 hours of readings or readings that failed our checks.
Oct 202521 of 31 days measured; a month needs 22. The others: 10 with under 18 hours of readings or readings that failed our checks.
Sep 202512 of 30 days measured; a month needs 21.

A day counts once 18 hours of it are measured; a month needs 70% of its days.

Yellowknife's worst months

MonthUS AQIDays measuredWorld rank
July 2026 11541.2 µg/m³28 of 3161stof 2,784
August 2026 5310.4 µg/m³27 of 31807thof 2,896
January 2026 122.2 µg/m³23 of 312,607thof 2,617
March 2026 122.2 µg/m³23 of 312,961stof 2,971
February 2026 111.9 µg/m³23 of 282,856thof 2,866
September 2026 30.5 µg/m³23 of 302,981stof 2,981

Monthly means over the days measured; finished months only. World rank: its place on that month's world ranking of every city with enough days. Each month opens that ranking.

Yellowknife's worst days

DayUS AQI
19 Jul 2026 246171.0 µg/m³
6 Jul 2026 206131.0 µg/m³
17 Jul 2026 185103.5 µg/m³
26 Sept 2025 17691.2 µg/m³
14 Jul 2026 17082.9 µg/m³
1 Jul 2026 16270.9 µg/m³
27 Sept 2025 16068.9 µg/m³
21 Jul 2026 15967.4 µg/m³
2 Jul 2026 15662.0 µg/m³
22 Jul 2026 14553.3 µg/m³

Daily means, the highest since 19 Sept 2025; the WHO's daily guideline is 15 µg/m³. Each date opens that day's world ranking, and each episode the bad-air spell it was part of.

Use this history

SmogRank, PM2.5 monthly and daily means, Yellowknife, Canada, 19 Sep 2025 – 11 Oct 2026. Monitor data from AirGradient via OpenAQ; sources listed at smogrank.com/sources. smogrank.com/ca/yellowknife/history (accessed 12 Oct 2026).

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You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.

Yellowknife now: the last 24 hours, its ranks today and the last 12 months day by day.

Updated 2026-10-12 17:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index. Some low-cost readings: Sensor.Community, ODbL (data and licence). Some readings: Uzhydromet (Uzbekistan's Hydrometeorological Service); Department of Environment, Nepal; Vietnam's government monitors; Aurassure; Umhverfisstofnun (Environment Agency of Iceland); RMCAB (Secretaría Distrital de Ambiente, Bogotá); Love My Air (City and County of Denver), no reuse terms published (why we use them).