Bad Air Days in Mobile County, Alabama: under 1 a Year

under 1 bad air day a year

Fewer bad air days than most monitored US counties. Ranked 702 of 996 monitored counties, where 1 is worst.

What makes them bad: mostly ozone: summer smog (33% particle days).

Which months to watch

Most bad days here fall in May. 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 record for Mobile

In 2000 to 2009 this county averaged 20 bad days a year; in 2016 to 2025, under 1. The air has improved. The worst recent year was 2017, with 5 bad days on 361 monitored days.

Date	AQI	Main pollutant
2016-07-21	139	PM2.5
2017-01-24	139	PM2.5
2017-03-08	138	PM2.5
2023-08-03	108	Ozone
2016-05-23	105	Ozone

An ordinary day in Mobile

Across 3,591 monitored days from 2016 to 2025, the air in Mobile County rated Good on 58% of them, less often than the 72% typical of monitored counties, and Moderate on 42%. The median day sat at AQI 47; one day in ten went above 61.

The pollutant setting the AQI on an ordinary day here:

fine particles (PM2.5)74%2,650 days
ozone26%931 days

Every recent year on file

Year	Days monitored	Good	Moderate	Over 100	Median AQI	Highest AQI
2025*	363	260	103	0	43	80
2024	365	242	123	0	45	80
2023	361	203	157	1	46	108
2022	363	235	128	0	44	93
2021	361	125	236	0	53	83
2020	348	188	160	0	49	78
2019	352	167	185	0	52	82
2018	359	218	140	1	44	105
2017	361	250	106	5	43	139
2016	358	179	177	2	51	139
2015	363	192	170	1	48	105
2014	285	206	73	6	43	115
2013	285	220	65	0	40	90
2012	284	211	70	3	40	126
2011	304	188	109	7	45	122
2010	363	245	110	8	42	140

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

Alabama 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.