Insights: Allentown-Bethlehem-Easton, PA-NJ metro. Aggregated EPA AQS monitors across this Core-Based Statistical Area logged a median Air Quality Index of 41 over 366 measured days in 2024, which corresponds to a Good band and a Moderate metro-wide health grade. The monitored-day split lands at 250 Good days (68%), 112 Moderate (31%), and 4 Unhealthy-for-Sensitive-Groups (1%). The 90th-percentile AQI finished at 65 while the highest single-day reading hit 119 (USG). Metro residents averaged roughly 20.5 clean-air days per 30-day window across the reporting year.

Across the 2020–2024 trend window, good days shifted by +16 and the median AQI moved -3 points, which classifies the multi-year trajectory as improving. The metro avoided any Unhealthy-tier days entirely, an outcome that typically reflects favorable wind patterns, lower industrial density, or effective regional emission controls. Metros with comparable AQI profiles include Ashtabula, OH (83.7% good, AQI 41); Bowling Green, KY (76.8% good, AQI 41); Dalton, GA (84.5% good, AQI 41).