Bad Air Days in Clearfield County, Pennsylvania: under 1 a Year

under 1 bad air days a year

Rare: among the cleanest-air counties EPA monitors. Ranked 874 of 996 monitored counties, where 1 is worst.

What makes them bad: mostly ozone: summer smog (0% 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.

Better or worse than it was

In 2000 to 2009 this county averaged 24 bad days a year; in 2016 to 2025, under 1. The air has improved. The worst recent year was 2016, with 1 bad day on 338 monitored days.

Date	AQI	Main pollutant
2016-05-25	119	Ozone
2018-05-26	101	Ozone
2018-05-01	100	Ozone
2016-04-18	97	Ozone
2022-06-21	97	Ozone

An ordinary day in Clearfield

Across 2,225 monitored days from 2016 to 2022, the air in Clearfield County rated Good on 96% of them, more often than the 72% typical of monitored counties, and Moderate on 4%. The median day sat at AQI 34; one day in ten went above 46.

The pollutant setting the AQI on an ordinary day here:

ozone100%2,225 days

Year by year

Year	Days monitored	Good	Moderate	Over 100	Over 150	Median AQI	Highest AQI
2022	219	215	4	0	0	35	97
2021	277	274	3	0	0	33	54
2020	343	341	2	0	0	31	54
2019	359	357	2	0	0	33	61
2018	343	320	22	1	0	33	101
2017	346	317	29	0	0	36	84
2016	338	305	32	1	0	38	119
2015	336	292	44	0	0	38	100
2014	263	250	13	0	0	32	93
2013	347	313	34	0	0	36	97
2012	342	290	46	6	1	35	164
2011	291	248	37	6	0	39	143
2010	206	135	56	15	0	45	136

Elsewhere in Pennsylvania

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.