SmogRank / United States / Oregon / Pendleton

Pendleton, month by month

Pendleton has a measured daily mean on 1,292 days since 1 January 2023. Its worst month was August 2026, at 78 US AQI (23.5 µg/m³), 187th of 2,896 cities on that month's world ranking. Its cleanest was May 2024, at 12 US AQI (2.1 µg/m³). 2025 averaged 32 US AQI (5.8 µg/m³), against 32 US AQI (5.7 µg/m³) in 2024.

Every month since 2023

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

2 months
MonthWhy
Mar 202311 of 31 days measured; a month needs 22. The others: 20 missing from OpenAQ's archive.
Feb 20231 of 28 days measured; a month needs 20. The others: 25 missing from OpenAQ's archive, 2 with under 18 hours of readings or readings that failed our checks.

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

Pendleton's worst months

MonthUS AQIDays measuredWorld rankEpisode
August 2026 7823.5 µg/m³31 of 31187thof 2,896North-western United States and Canada, 4 to 22 August 2026
North-western United States and Canada, July and August 2026
August 2023 7220.3 µg/m³31 of 31121stof 1,980North-western United States and Canada, August 2023
July 2026 6918.6 µg/m³31 of 31372ndof 2,784North-western United States and Canada, July and August 2026
January 2026 5712.2 µg/m³31 of 31917thof 2,617–
July 2024 5310.2 µg/m³29 of 31687thof 2,566North-western United States and Canada, July 2024
September 2025 5310.0 µg/m³30 of 30690thof 3,104–

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.

Pendleton's worst days

DayUS AQIEpisode
20 Aug 2023 255180.0 µg/m³North-western United States and Canada, August 2023
21 Aug 2023 200125.0 µg/m³North-western United States and Canada, August 2023
5 Aug 2026 17386.3 µg/m³North-western United States and Canada, 4 to 22 August 2026
4 Aug 2026 16778.6 µg/m³North-western United States and Canada, 4 to 22 August 2026
North-western United States and Canada, July and August 2026
6 Aug 2026 16778.2 µg/m³North-western United States and Canada, 4 to 22 August 2026
21 Jul 2026 16575.1 µg/m³North-western United States and Canada, July and August 2026
10 Jan 2026 16169.9 µg/m³–
22 Jul 2026 15662.7 µg/m³North-western United States and Canada, July and August 2026
20 Jul 2026 15662.4 µg/m³North-western United States and Canada, July and August 2026
19 Aug 2023 15662.3 µg/m³North-western United States and Canada, August 2023

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, Pendleton, 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/pendleton/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.

Pendleton 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).