Bad Air Days in Harrison County, Texas: 1 a Year
1 bad air day a year
Fewer bad air days than most monitored US counties. Ranked 597 of 996 monitored counties, where 1 is worst.
What makes them bad: mostly particles: smoke and dust (86% particle days).
When the bad days come in Harrison
- J
- F
- M
- A
- M
- J
- J
- A
- S
- O
- N
- D
Most bad days here fall in April and March and January and June. Averaged over 2016 to 2025.
Is a purifier worth it here?
- Bad air days are rare here. A standard furnace filter is enough; no purifier needed for outdoor air.
- On the odd bad day, check AirNow and keep windows shut.
Better or worse than it was
In 2000 to 2009 this county averaged 12 bad days a year; in 2016 to 2025, 1. The air has improved. The worst recent year was 2022, with 5 bad days on 328 monitored days.
| Date | AQI | Main pollutant |
|---|---|---|
| 2024-04-05 | 263 | PM2.5 |
| 2024-04-04 | 205 | PM2.5 |
| 2022-01-21 | 181 | PM2.5 |
| 2024-04-06 | 168 | PM2.5 |
| 2021-04-04 | 161 | PM2.5 |
The air on a normal day
Across 3,593 monitored days from 2016 to 2025, the air in Harrison County rated Good on 64% of them, less often than the 72% typical of monitored counties, and Moderate on 36%. The median day sat at AQI 45; one day in ten went above 60.
The pollutant setting the AQI on an ordinary day here:
- fine particles (PM2.5)67%2,415 days
- ozone33%1,174 days
Harrison County by year
| Year | Days monitored | Good | Moderate | Over 100 | Over 150 | Median AQI | Highest AQI |
|---|---|---|---|---|---|---|---|
| 2025* | 365 | 235 | 130 | 0 | 0 | 44 | 100 |
| 2024 | 365 | 233 | 129 | 3 | 3 | 44 | 263 |
| 2023 | 359 | 207 | 151 | 1 | 0 | 47 | 111 |
| 2022 | 328 | 164 | 159 | 5 | 1 | 51 | 181 |
| 2021 | 362 | 205 | 153 | 4 | 1 | 47 | 161 |
| 2020 | 363 | 264 | 99 | 0 | 0 | 40 | 100 |
| 2019 | 358 | 242 | 116 | 0 | 0 | 44 | 90 |
| 2018 | 364 | 263 | 100 | 1 | 0 | 41 | 111 |
| 2017 | 363 | 218 | 145 | 0 | 0 | 46 | 100 |
| 2016 | 366 | 265 | 101 | 0 | 0 | 42 | 79 |
| 2015 | 365 | 251 | 114 | 0 | 0 | 42 | 96 |
| 2014 | 365 | 238 | 126 | 1 | 0 | 45 | 101 |
| 2013 | 365 | 213 | 149 | 3 | 0 | 47 | 108 |
| 2012 | 366 | 159 | 200 | 7 | 0 | 52 | 133 |
| 2011 | 365 | 139 | 208 | 18 | 1 | 54 | 215 |
| 2010 | 365 | 161 | 195 | 9 | 0 | 52 | 126 |
*2025 may be a partial year in EPA's file.
Elsewhere in Texas
- Harris County29/yr
- El Paso County26/yr
- Tarrant County19/yr
- Denton County17/yr
- Dallas County12/yr
- Collin County11/yr
- Bexar County11/yr
- Cameron County9/yr
How this is counted
A bad air day is a day the county's daily AQI from EPA AirData went above 100, the level where EPA tells children, older adults and people with asthma or heart disease to cut back outdoors. Monitors do not run every day, so yearly counts are scaled to 365 days. This is the record, not today's air: for that, check AirNow. More on the method in how the county numbers are made, on the AQI 100 line in what counts as a bad air day.