SmogRank / United States / Utah / West Valley City
West Valley City, month by month
West Valley City has a measured daily mean on 974 days since 11 January 2023. Its worst month was July 2024, at 61 US AQI (14.6 µg/m³), 196th of 2,566 cities on that month's world ranking. Its cleanest was April 2024, at 23 US AQI (4.1 µg/m³). 2025 averaged 41 US AQI (7.3 µg/m³), against 43 US AQI (7.8 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
14 months
| Month | Why |
|---|---|
| Mar 2024 | 13 of 31 days measured; a month needs 22. The others: 18 with under 18 hours of readings or readings that failed our checks. |
| Feb 2024 | 1 of 29 days measured; a month needs 21. The others: 28 with under 18 hours of readings or readings that failed our checks. |
| Jan 2024 | No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks. |
| Dec 2023 | No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks. |
| Nov 2023 | No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks. |
| Oct 2023 | No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks. |
| Sep 2023 | No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks. |
| Aug 2023 | No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks. |
| Jul 2023 | 1 of 31 days measured; a month needs 22. The others: 30 with under 18 hours of readings or readings that failed our checks. |
| Jun 2023 | No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks. |
| May 2023 | No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks. |
| Apr 2023 | 3 of 30 days measured; a month needs 21. The others: 27 with under 18 hours of readings or readings that failed our checks. |
| Mar 2023 | 20 of 31 days measured; a month needs 22. The others: 11 with under 18 hours of readings or readings that failed our checks. |
| Jan 2023 | 7 of 31 days measured; a month needs 22. The others: 14 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.
West Valley City's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| July 2024 | 6114.6 µg/m³ | 196thof 2,566 | North-western United States and Canada, July 2024 |
| January 2026 | 5913.2 µg/m³ | 859thof 2,617 | – |
| December 2024 | 5812.7 µg/m³ | 611thof 2,616 | – |
| February 2023 | 5712.5 µg/m³ | 512thof 1,129 | Utah and Idaho, United States, February 2023 |
| July 2025 | 5310.1 µg/m³ | 1,244thof 2,889 | – |
| November 2025 | 529.7 µg/m³ | 1,094thof 2,715 | – |
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.
West Valley City's worst days
| Day | US AQI | Episode |
|---|---|---|
| 5 Jul 2024 | 17083.3 µg/m³ | – |
| 5 Jul 2025 | 12745.9 µg/m³ | – |
| 4 Feb 2023 | 11842.3 µg/m³ | Utah and Idaho, United States, February 2023 |
| 3 Feb 2023 | 11240.1 µg/m³ | Utah and Idaho, United States, February 2023 |
| 5 Dec 2024 | 9834.5 µg/m³ | – |
| 2 Feb 2023 | 9733.9 µg/m³ | Utah and Idaho, United States, February 2023 |
| 4 Dec 2024 | 9633.3 µg/m³ | – |
| 1 Jan 2026 | 9532.7 µg/m³ | – |
| 11 Sept 2024 | 9432.4 µg/m³ | North-western United States and Canada, 4 to 11 September 2024 |
| 4 Jul 2024 | 9331.4 µg/m³ | – |
Daily means, the highest since 11 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, West Valley City, United States, 11 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/west-valley-city/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.
West Valley City now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-12 22:07 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).