Bad Air Days in Collier County, Florida: under 1 a Year

under 1 bad air days a year

Rare: among the cleanest-air counties EPA monitors. Ranked 949 of 996 monitored counties, where 1 is worst.

What makes them bad: mostly particles: smoke and dust (100% particle days).

When the bad days come in Collier

Most bad days here fall in October. Averaged over 2016 to 2025.

What actually helps 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 2 bad days a year; in 2016 to 2025, under 1. The air has improved. The worst recent year was 2023, with 1 bad day on 360 monitored days.

Date	AQI	Main pollutant
2023-10-03	144	PM2.5
2017-05-09	93	Ozone
2019-04-16	90	Ozone
2023-07-24	89	PM2.5
2016-05-08	87	Ozone

Most days, not the worst ones

Across 3,615 monitored days from 2016 to 2025, the air in Collier County rated Good on 76% of them, more often than the 72% typical of monitored counties, and Moderate on 24%. The median day sat at AQI 42; one day in ten went above 56.

The pollutant setting the AQI on an ordinary day here:

fine particles (PM2.5)68%2,466 days
ozone32%1,149 days

Collier County by year

Year	Days monitored	Good	Moderate	Over 100	Median AQI	Highest AQI
2025*	365	263	102	0	43	71
2024	366	279	87	0	42	87
2023	360	259	100	1	43	144
2022	347	277	70	0	40	82
2021	363	278	85	0	42	81
2020	364	267	97	0	41	87
2019	362	291	71	0	40	90
2018	365	262	103	0	42	80
2017	357	270	87	0	39	93
2016	366	286	80	0	43	87
2015	363	279	84	0	39	77
2014	365	265	100	0	42	79
2013	365	264	101	0	42	74
2012	365	254	111	0	44	86
2011	365	227	136	2	44	110
2010	362	218	144	0	46	93

*2025 may be a partial year in EPA's file.

Florida compared

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.