SmogRank / United States / Utah / Smithfield
Smithfield, month by month
Smithfield has a measured daily mean on 1,282 days since 1 January 2023. Its worst month was January 2024, at 58 US AQI (12.6 µg/m³), 633rd of 2,385 cities on that month's world ranking. Its cleanest was March 2024, at 16 US AQI (2.9 µg/m³). 2025 averaged 35 US AQI (6.3 µg/m³), against 39 US AQI (7.1 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
2 months
| Month | Why |
|---|---|
| Mar 2023 | 11 of 31 days measured; a month needs 22. The others: 20 missing from OpenAQ's archive. |
| Feb 2023 | 3 of 28 days measured; a month needs 20. The others: 25 missing from OpenAQ's archive. |
A day counts once 18 hours of it are measured; a month needs 70% of its days.
Smithfield's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| January 2024 | 5812.6 µg/m³ | 633rdof 2,385 | – |
| July 2024 | 5712.2 µg/m³ | 402ndof 2,566 | – |
| December 2023 | 5511.1 µg/m³ | 521stof 2,247 | – |
| August 2026 | 5511.0 µg/m³ | 699thof 2,896 | North-western United States and Canada, July and August 2026 |
| August 2024 | 5410.9 µg/m³ | 462ndof 2,010 | North-western United States, August and September 2024 Oregon, Idaho and Utah, United States, August 2024 |
| January 2023 | 5410.6 µg/m³ | 426thof 1,261 | – |
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.
Smithfield's worst days
| Day | US AQI | Episode |
|---|---|---|
| 1 Feb 2023 | 11641.6 µg/m³ | Utah and Idaho, United States, February 2023 |
| 23 Feb 2026 | 9331.6 µg/m³ | – |
| 4 Sept 2024 | 9331.4 µg/m³ | North-western United States and Canada, 4 to 11 September 2024 |
| 8 Aug 2024 | 9231.3 µg/m³ | Oregon, Idaho and Utah, United States, August 2024 |
| 30 Aug 2024 | 9231.0 µg/m³ | North-western United States, August and September 2024 |
| 17 Jan 2024 | 8728.6 µg/m³ | – |
| 5 Jan 2023 | 8527.6 µg/m³ | – |
| 9 Aug 2024 | 8527.3 µg/m³ | Oregon, Idaho and Utah, United States, August 2024 |
| 30 Nov 2023 | 8326.4 µg/m³ | Utah and Idaho, United States, November 2023 |
| 28 Mar 2025 | 8326.1 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, Smithfield, 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/smithfield-utah/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.
Smithfield now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-12 21:07 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).