Raleigh Best & Worst AQI Days: Air Quality Guide

The worst air quality day on record for Raleigh (Raleigh, NC area) was June 22, 2022, when the daily AQI reached 140 (Unhealthy for Sensitive Groups), set by ground-level ozone, in peak ozone season. Across 2,556 monitored days in 2019–2025, 0 of the 10 worst days were Unhealthy (AQI 151+) or worse; 6 of the 10 were driven by fine particulate matter (PM2.5) and 4 by ground-level ozone, and 5 of them fell in 2023. The cleanest day was August 2, 2020 at AQI 2 (Good); the 10 best days span 6 different years.

140
Worst day AQI
2022-06-22
2
Best day AQI
2020-08-02
0
Top-10 days at 151+
Unhealthy or worse
2,556
Days monitored
2019–2025

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QUICK ANSWER

When were Raleigh's worst and best air quality days?

Worst: June 22, 2022, AQI 140 (Unhealthy for Sensitive Groups, O3). Best: August 2, 2020, AQI 2 (Good). Based on 2,556 EPA-monitored days in the Raleigh, NC area, 2019–2025.

  • 0 of the 10 worst days were Unhealthy (AQI 151+) or worse; the 10th-worst was AQI 97 (Moderate).
  • Fine particulate matter (PM2.5) drove 6 of the 10 worst days.
  • 2023 accounts for 5 of the 10 worst days.

Frequently asked questions

What was the worst air quality day in Raleigh?

June 22, 2022: the Raleigh, NC area's daily AQI hit 140 (Unhealthy for Sensitive Groups), driven by ground-level ozone, in peak ozone season. That is the highest of 2,556 monitored days in 2019–2025.

What was the best air quality day in Raleigh?

August 2, 2020, with a daily AQI of 2 (Good). The daily AQI is the highest reading from any monitor in the area, so even the cleanest day reflects the area's worst monitor.

What was Raleigh's worst air quality day in 2025?

March 12, 2025, AQI 84 (Moderate), set by ground-level ozone.

Which pollutant causes Raleigh's worst air days?

Fine particulate matter (PM2.5) set the AQI on 6 of the 10 worst days; ground-level ozone on 4. The tables above list the defining pollutant for every day.

Raleigh's 10 worst air quality days, 2019–2025

Highest daily AQI recorded for the Raleigh, NC area (EPA AQS). The daily AQI is the highest reading from any monitor in the area that day.

#DateAQICategoryDefining pollutant
1 (2022 page)140Unhealthy for Sensitive GroupsO3ground-level ozone, in peak ozone season
2 (2023 page)130Unhealthy for Sensitive GroupsPM2.5fine particulate matter (PM2.5), in wildfire smoke season
3 (2023 page)126Unhealthy for Sensitive GroupsPM2.5fine particulate matter (PM2.5), in wildfire smoke season
4 (2023 page)125Unhealthy for Sensitive GroupsPM2.5fine particulate matter (PM2.5), in wildfire smoke season
5 (2024 page)112Unhealthy for Sensitive GroupsO3ground-level ozone, in peak ozone season
6 (2023 page)110Unhealthy for Sensitive GroupsPM2.5fine particulate matter (PM2.5), in wildfire smoke season
7 (2023 page)108Unhealthy for Sensitive GroupsPM2.5fine particulate matter (PM2.5), in wildfire smoke season
8 (2020 page)101Unhealthy for Sensitive GroupsPM2.5fine particulate matter (PM2.5), in wildfire smoke season
9 (2022 page)100ModerateO3ground-level ozone, in peak ozone season
10 (2024 page)97ModerateO3ground-level ozone, in peak ozone season

Worst day of each year in Raleigh

The single highest-AQI day in each year on record. Click a year for its full month-by-month statistics.

YearWorst dayAQICategoryDefining pollutant
201993ModerateO3ground-level ozone, in peak ozone season
2020101Unhealthy for Sensitive GroupsPM2.5fine particulate matter (PM2.5), in wildfire smoke season
202197ModerateO3ground-level ozone
2022140Unhealthy for Sensitive GroupsO3ground-level ozone, in peak ozone season
2023130Unhealthy for Sensitive GroupsPM2.5fine particulate matter (PM2.5), in wildfire smoke season
2024112Unhealthy for Sensitive GroupsO3ground-level ozone, in peak ozone season
202584ModerateO3ground-level ozone

Raleigh's 10 best air quality days, 2019–2025

Lowest daily AQI recorded for the Raleigh, NC area. Ties are listed most recent first.

#DateAQICategoryDefining pollutant
1 (2020 page)2GoodCOcarbon monoxide
2 (2019 page)2GoodCOcarbon monoxide
3 (2022 page)13GoodPM2.5fine particulate matter (PM2.5)
4 (2022 page)16GoodO3ground-level ozone
5 (2024 page)18GoodO3ground-level ozone
6 (2023 page)19GoodO3ground-level ozone
7 (2023 page)19GoodO3ground-level ozone
8 (2025 page)20GoodPM2.5fine particulate matter (PM2.5)
9 (2024 page)20GoodPM2.5fine particulate matter (PM2.5)
10 (2024 page)20GoodO3ground-level ozone

Right now in Raleigh

The latest EPA AirNow observation puts Raleigh's AQI at 47 (PM2.5). The days above are historical records, not today's reading.

View current Raleigh air quality →

Source: EPA Air Quality System (AQS) pre-generated Daily AQI by CBSA files — daily AQI by CBSA (Raleigh, NC), 2019–2025. Daily AQI per CBSA is the highest AQI reported by any monitor in the area that day; the defining parameter is the pollutant that set it. Month and season statistics pool every such day in the period across all years listed. Retrieved 2026-09-09.