SmogRank / United States / Oregon / Salem

Salem, month by month

Salem, Oregon has a measured daily mean on 1,310 days since 1 January 2023. Its worst month was November 2023, at 59 US AQI (13.2 µg/m³), 215th of 2,243 cities on that month's world ranking. Its cleanest was June 2024, at 15 US AQI (2.7 µg/m³). 2025 averaged 30 US AQI (5.4 µg/m³), against 29 US AQI (5.2 µg/m³) in 2024.

Every month since 2023

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

Salem's worst months

MonthUS AQIDays measuredWorld rankEpisode
November 2023 5913.2 µg/m³30 of 30215thof 2,243North-western United States and Canada, October and November 2023
January 2025 5410.6 µg/m³31 of 31899thof 2,474Western United States and Mexico, January and February 2025
January 2026 5410.6 µg/m³31 of 311,021stof 2,617Washington and Oregon, United States, January 2026
August 2026 5310.0 µg/m³31 of 31895thof 2,896North-western United States and Canada, 4 to 22 August 2026
November 2024 529.7 µg/m³30 of 30909thof 2,624North-western United States and Canada, November 2024
October 2023 519.1 µg/m³31 of 31474thof 2,012North-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.

Salem's worst days

DayUS AQIEpisode
5 Aug 2026 15764.4 µg/m³North-western United States and Canada, 4 to 22 August 2026
4 Aug 2026 15561.2 µg/m³North-western United States and Canada, 4 to 22 August 2026
9 Nov 2024 11440.9 µg/m³North-western United States and Canada, November 2024
1 Nov 2023 10838.3 µg/m³North-western United States and Canada, October and November 2023
10 Nov 2024 10738.0 µg/m³North-western United States and Canada, November 2024
8 Nov 2024 10336.3 µg/m³North-western United States and Canada, November 2024
20 Aug 2023 9934.6 µg/m³North-western United States and Canada, August 2023
31 Oct 2023 9734.0 µg/m³North-western United States and Canada, October and November 2023
6 Aug 2026 9633.4 µg/m³North-western United States and Canada, 4 to 22 August 2026
29 Nov 2023 9633.1 µg/m³–

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, Salem, Oregon, 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/salem/history (accessed 12 Oct 2026).

Download chart (PNG)

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.

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

Updated 2026-10-12 18:07 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).