Bad Air Days in Webster County, Iowa: 8 a Year
8 bad air days a year
More bad air days than three quarters of monitored counties. Ranked 119 of 996 monitored counties, where 1 is worst.
What makes them bad: mostly particles: smoke and dust (100% particle days).
The bad-air season here
- J
- F
- M
- A
- M
- J
- J
- A
- S
- O
- N
- D
Most bad days here fall in July and August. Averaged over 2016 to 2025.
Is a purifier worth it here?
- Particles (wildfire smoke, dust) cause enough bad days here to matter. A HEPA purifier sized to your bedroom removes them; run it with windows shut on bad days.
- Upgrade the furnace or AC filter to MERV 13 so the whole house is filtered, not just one room.
Better or worse than it was
The worst recent year was 2025, with 4 bad days on 184 monitored days.
| Date | AQI | Main pollutant |
|---|---|---|
| 2025-07-31 | 165 | PM2.5 |
| 2025-08-01 | 158 | PM2.5 |
| 2025-08-02 | 124 | PM2.5 |
| 2025-07-13 | 102 | PM2.5 |
| 2025-09-04 | 84 | PM2.5 |
An ordinary day in Webster
Across 184 monitored days from 2025 to 2025, the air in Webster County rated Good on 59% of them, less often than the 72% typical of monitored counties, and Moderate on 39%. The median day sat at AQI 45; one day in ten went above 65.
The pollutant setting the AQI on an ordinary day here:
- fine particles (PM2.5)86%158 days
- coarse dust (PM10)14%26 days
Every recent year on file
| Year | Days monitored | Good | Moderate | Over 100 | Over 150 | Median AQI | Highest AQI |
|---|---|---|---|---|---|---|---|
| 2025* | 184 | 109 | 71 | 4 | 2 | 45 | 165 |
*2025 may be a partial year in EPA's file.
Elsewhere in Iowa
- Scott County4/yr
- Palo Alto County4/yr
- Linn County3/yr
- Harrison County3/yr
- Clinton County3/yr
- Polk County2/yr
- Bremer County2/yr
- Woodbury Countythin data
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.