Bad Air Days in Navarro County, Texas: 2 a Year

2 bad air days a year

Fewer bad air days than most monitored US counties. Ranked 553 of 996 monitored counties, where 1 is worst.

What makes them bad: mostly ozone: summer smog (35% particle days).

Which months to watch

Most bad days here fall in June and May and July. 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.

The worst days on file

In 2000 to 2009 this county averaged 0 bad days a year; in 2016 to 2025, 2. Not much has changed. The worst recent year was 2024, with 8 bad days on 366 monitored days.

Date	AQI	Main pollutant
2024-10-15	129	Ozone
2024-07-09	126	Ozone
2018-07-01	117	PM2.5
2020-06-26	113	PM2.5
2024-05-14	112	Ozone

An ordinary day in Navarro

Across 3,645 monitored days from 2016 to 2025, the air in Navarro County rated Good on 67% of them, less often than the 72% typical of monitored counties, and Moderate on 33%. The median day sat at AQI 44; one day in ten went above 64.

The pollutant setting the AQI on an ordinary day here:

ozone51%1,869 days
fine particles (PM2.5)48%1,767 days

Navarro County by year

Year	Days monitored	Good	Moderate	Over 100	Over 150	Median AQI	Highest AQI
2025*	363	215	147	1	0	47	107
2024	366	205	153	8	0	48	129
2023	364	217	147	0	0	46	100
2022	364	242	121	1	0	44	101
2021	365	266	99	0	0	41	100
2020	366	257	107	2	0	42	113
2019	362	275	87	0	0	42	100
2018	364	266	94	4	0	41	117
2017	365	233	131	1	0	46	108
2016	366	260	106	0	0	43	85
2015	364	234	129	1	0	43	105
2014	364	215	149	0	0	47	93
2013	365	207	153	5	0	47	126
2012	366	206	158	2	1	48	159
2011	365	162	190	13	0	52	147
2010	364	196	167	1	0	49	105

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

Texas 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, and on why a purifier does not touch ozone in smoke vs ozone.