SmogRank / United States / Washington / Yakima

Yakima, month by month

Yakima has a measured daily mean on 1,347 days since 1 January 2023. Its worst month was August 2026, at 76 US AQI (22.4 µg/m³), 197th of 2,896 cities on that month's world ranking. Its cleanest was May 2024, at 17 US AQI (3.1 µg/m³). 2025 averaged 47 US AQI (8.5 µg/m³), against 41 US AQI (7.3 µg/m³) in 2024.

Every month since 2023

Each square is a month's mean PM2.5 in US AQI from Yakima'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 Yakima 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

Yakima's worst months

MonthUS AQIDays measuredWorld rankEpisode
August 2026 7622.4 µg/m³31 of 31197thof 2,896North-western United States and Canada, 4 to 22 August 2026
North-western United States and Canada, July and August 2026
August 2023 6918.8 µg/m³31 of 31141stof 1,980North-western United States and Canada, August 2023
September 2025 6818.3 µg/m³30 of 30251stof 3,104North-western Canada and United States, September 2025
North-western United States and Canada, August and September 2025
January 2026 6114.3 µg/m³31 of 31793rdof 2,617Washington, United States, January 2026
January 2023 6014.0 µg/m³30 of 31276thof 1,261–
November 2023 6013.7 µg/m³30 of 30194thof 2,243North-western United States and Canada, October and November 2023

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.

Yakima's worst days

DayUS AQIEpisode
21 Aug 2023 216141.0 µg/m³North-western United States and Canada, August 2023
20 Aug 2023 215140.0 µg/m³North-western United States and Canada, August 2023
4 Aug 2026 18299.9 µg/m³North-western United States and Canada, 4 to 22 August 2026
North-western United States and Canada, July and August 2026
5 Aug 2026 17691.2 µg/m³North-western United States and Canada, 4 to 22 August 2026
19 Aug 2023 16677.5 µg/m³North-western United States and Canada, August 2023
25 Jul 2024 15358.4 µg/m³North-western United States and Canada, July 2024
4 Sept 2025 15358.0 µg/m³North-western United States and Canada, August and September 2025
6 Aug 2026 15156.1 µg/m³North-western United States and Canada, 4 to 22 August 2026
13 Aug 2026 13348.5 µg/m³North-western United States and Canada, 4 to 22 August 2026
3 Aug 2026 13047.3 µg/m³North-western United States and Canada, July and August 2026

Daily means, the highest since 1 Jan 2023; 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, Yakima, United States, 1 Jan 2023 – 11 Oct 2026. Monitor data from AirNow, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/us/yakima/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.

Yakima 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).