SmogRank / United States / Pennsylvania / Allentown
Allentown, month by month
Allentown has a measured daily mean on 1,319 days since 1 January 2023. Its worst month was June 2023, at 90 US AQI (29.8 µg/m³), 92nd of 1,603 cities on that month's world ranking. Its cleanest was October 2025, at 22 US AQI (3.9 µg/m³). 2025 averaged 37 US AQI (6.7 µg/m³), against 37 US AQI (6.6 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 |
|---|---|
| Aug 2025 | 21 of 31 days measured; a month needs 22. The others: 10 with under 18 hours of readings or readings that failed our checks. |
| Jul 2025 | 21 of 31 days measured; a month needs 22. The others: 10 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.
Allentown's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| June 2023 | 9029.8 µg/m³ | 92ndof 1,603 | Eastern United States and Canada, June and July 2023 Eastern United States and Canada, May and June 2023 |
| July 2026 | 5813.1 µg/m³ | 712thof 2,784 | Northern United States and Canada, July 2026 |
| February 2026 | 5611.8 µg/m³ | 1,048thof 2,866 | North-eastern United States and Canada, 14 to 19 February 2026 |
| July 2023 | 5611.6 µg/m³ | 448thof 1,432 | United States and Canada, July 2023 North-eastern United States, 19 July 2023and 1 more |
| December 2023 | 529.5 µg/m³ | 824thof 2,247 | North-eastern United States, December 2023 |
| February 2023 | 529.4 µg/m³ | 705thof 1,129 | – |
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.
Allentown's worst days
| Day | US AQI | Episode |
|---|---|---|
| 7 Jun 2023 | 328239.0 µg/m³ | Eastern United States and Canada, May and June 2023 |
| 8 Jun 2023 | 200125.0 µg/m³ | Eastern United States and Canada, May and June 2023 |
| 6 Jun 2023 | 16677.6 µg/m³ | Eastern United States and Canada, May and June 2023 |
| 29 Jun 2023 | 16676.7 µg/m³ | Eastern United States and Canada, June and July 2023 |
| 30 Jun 2023 | 16676.2 µg/m³ | Eastern United States and Canada, June and July 2023 |
| 18 Jul 2026 | 16372.4 µg/m³ | Northern United States and Canada, July 2026 |
| 17 Jul 2026 | 16372.0 µg/m³ | Northern United States and Canada, July 2026 |
| 1 Jul 2023 | 10436.7 µg/m³ | Eastern United States and Canada, June and July 2023 |
| 18 Feb 2026 | 10035.3 µg/m³ | North-eastern United States and Canada, 14 to 19 February 2026 |
| 17 Jul 2023 | 9331.7 µg/m³ | United States and Canada, July 2023 |
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, Allentown, 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/allentown/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.
Allentown 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).