SmogRank / United States / California / Guadalupe
Guadalupe, month by month
Guadalupe, California has a measured daily mean on 1,276 days since 1 January 2023. Its worst month was May 2025, at 58 US AQI (12.7 µg/m³), 538th of 2,826 cities on that month's world ranking. Its cleanest was February 2024, at 16 US AQI (2.9 µg/m³). 2025 averaged 41 US AQI (7.4 µg/m³), against 33 US AQI (6.0 µg/m³) in 2024.
Every month since 2023
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
3 months
| Month | Why |
|---|---|
| Jul 2024 | 19 of 31 days measured; a month needs 22. The others: 12 with under 18 hours of readings or readings that failed our checks. |
| Mar 2023 | 11 of 31 days measured; a month needs 22. The others: 20 missing from OpenAQ's archive. |
| Feb 2023 | 1 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.
Guadalupe's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| May 2025 | 5812.7 µg/m³ | 538thof 2,826 | – |
| September 2023 | 5410.8 µg/m³ | 451stof 2,176 | California and Oregon, United States, September 2023 |
| April 2025 | 5410.6 µg/m³ | 1,032ndof 2,951 | – |
| June 2025 | 529.7 µg/m³ | 1,391stof 2,508 | – |
| March 2025 | 529.6 µg/m³ | 1,665thof 2,862 | – |
| March 2026 | 519.2 µg/m³ | 1,840thof 2,971 | – |
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.
Guadalupe's worst days
| Day | US AQI | Episode |
|---|---|---|
| 20 Sept 2023 | 9834.1 µg/m³ | California and Oregon, United States, September 2023 |
| 21 Sept 2023 | 9331.8 µg/m³ | California and Oregon, United States, September 2023 |
| 22 Sept 2023 | 8829.0 µg/m³ | California and Oregon, United States, September 2023 |
| 29 Aug 2023 | 8728.3 µg/m³ | North-western United States and Canada, August 2023 |
| 21 Jun 2025 | 8225.8 µg/m³ | – |
| 16 Jun 2024 | 8024.8 µg/m³ | – |
| 23 Sept 2023 | 8024.6 µg/m³ | California and Oregon, United States, September 2023 |
| 13 Sept 2026 | 8024.4 µg/m³ | – |
| 16 May 2026 | 7924.3 µg/m³ | – |
| 30 Apr 2024 | 7823.4 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, Guadalupe, California, 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/guadalupe/history (accessed 12 Oct 2026).
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.
Guadalupe now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-12 23:07 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).