SmogRank / United States / Iowa / Iowa City
Iowa City, month by month
Iowa City has a measured daily mean on 1,297 days since 11 January 2023. Its worst month was June 2023, at 88 US AQI (28.9 µg/m³), 108th of 1,603 cities on that month's world ranking. Its cleanest was June 2026, at 29 US AQI (5.2 µg/m³). 2025 averaged 47 US AQI (8.4 µg/m³), against 41 US AQI (7.4 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 |
|---|---|
| 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.
Iowa City's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| June 2023 | 8828.9 µg/m³ | 108thof 1,603 | Eastern United States and Canada, June and July 2023 United States and Canada, June 2023and 1 more |
| June 2025 | 6014.1 µg/m³ | 534thof 2,508 | Northern United States and Canada, May and June 2025 |
| July 2023 | 5813.1 µg/m³ | 275thof 1,432 | United States and Canada, July 2023 Eastern United States and Canada, June and July 2023 |
| July 2026 | 5812.6 µg/m³ | 791stof 2,784 | Northern United States and Canada, July 2026 |
| August 2023 | 5611.8 µg/m³ | 367thof 1,980 | Northern United States and Canada, August and September 2023 |
| September 2023 | 5511.4 µg/m³ | 388thof 2,176 | Northern United States and Canada, August and September 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.
Iowa City's worst days
| Day | US AQI | Episode |
|---|---|---|
| 28 Jun 2023 | 210135.0 µg/m³ | Eastern United States and Canada, June and July 2023 |
| 27 Jun 2023 | 195118.0 µg/m³ | Eastern United States and Canada, June and July 2023 |
| 29 Jun 2023 | 191112.0 µg/m³ | Eastern United States and Canada, June and July 2023 |
| 19 Jul 2026 | 16067.7 µg/m³ | Northern United States and Canada, July 2026 |
| 31 Jul 2025 | 15864.9 µg/m³ | North-eastern United States and Canada, 29 July to 9 August 2025 |
| 16 Jul 2023 | 15662.4 µg/m³ | United States and Canada, July 2023 |
| 1 Aug 2025 | 13248.1 µg/m³ | North-eastern United States and Canada, 29 July to 9 August 2025 |
| 15 Jun 2023 | 12846.3 µg/m³ | United States and Canada, June 2023 |
| 4 Jun 2025 | 11340.5 µg/m³ | Northern United States and Canada, May and June 2025 |
| 15 Jul 2023 | 10537.0 µg/m³ | United States and Canada, July 2023 |
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, Iowa City, United States, 11 Jan 2023 – 12 Oct 2026. Monitor data from AirNow, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/us/iowa-city/history (accessed 13 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.
Iowa City now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-13 05:07 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).