Bad Air Days in Pasco County, Florida: under 1 a Year
under 1 bad air day a year
Rare: among the cleanest-air counties EPA monitors. Ranked 784 of 996 monitored counties, where 1 is worst.
What makes them bad: mostly ozone: summer smog (0% 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 May and April and March. Averaged over 2016 to 2025.
What to buy, and what not to
- 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.
The worst days on file
In 2000 to 2009 this county averaged 12 bad days a year; in 2016 to 2025, under 1. The air has improved. The worst recent year was 2017, with 2 bad days on 348 monitored days.
| Date | AQI | Main pollutant |
|---|---|---|
| 2018-04-18 | 129 | Ozone |
| 2025-04-17 | 115 | Ozone |
| 2017-05-09 | 112 | Ozone |
| 2016-05-09 | 105 | Ozone |
| 2017-05-10 | 101 | Ozone |
The air on a normal day
Across 3,620 monitored days from 2016 to 2025, the air in Pasco County rated Good on 92% of them, more often than the 72% typical of monitored counties, and Moderate on 8%. The median day sat at AQI 37; one day in ten went above 50.
The pollutant setting the AQI on an ordinary day here:
- ozone100%3,620 days
Every recent year on file
| Year | Days monitored | Good | Moderate | Over 100 | Over 150 | Median AQI | Highest AQI |
|---|---|---|---|---|---|---|---|
| 2025* | 365 | 338 | 26 | 1 | 0 | 37 | 115 |
| 2024 | 354 | 320 | 34 | 0 | 0 | 39 | 97 |
| 2023 | 365 | 323 | 42 | 0 | 0 | 39 | 97 |
| 2022 | 361 | 332 | 29 | 0 | 0 | 37 | 87 |
| 2021 | 365 | 346 | 19 | 0 | 0 | 35 | 87 |
| 2020 | 366 | 355 | 11 | 0 | 0 | 35 | 77 |
| 2019 | 365 | 336 | 29 | 0 | 0 | 36 | 97 |
| 2018 | 365 | 324 | 39 | 2 | 0 | 35 | 129 |
| 2017 | 348 | 312 | 34 | 2 | 0 | 37 | 112 |
| 2016 | 366 | 328 | 37 | 1 | 0 | 37 | 105 |
| 2015 | 365 | 343 | 22 | 0 | 0 | 37 | 90 |
| 2014 | 365 | 331 | 33 | 1 | 0 | 35 | 108 |
| 2013 | 365 | 336 | 28 | 1 | 0 | 36 | 101 |
| 2012 | 366 | 325 | 41 | 0 | 0 | 38 | 100 |
| 2011 | 364 | 308 | 52 | 4 | 0 | 38 | 108 |
| 2010 | 365 | 304 | 61 | 0 | 0 | 39 | 97 |
*2025 may be a partial year in EPA's file.
Florida compared
- Hillsborough County3/yr
- Miami-Dade County3/yr
- Duval County2/yr
- Broward County1/yr
- Osceola County1/yr
- Orange Countyunder 1/yr
- Polk Countyunder 1/yr
- Pinellas Countyunder 1/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, and on why a purifier does not touch ozone in smoke vs ozone.