Bad Air Days in St John, Virgin Islands

Not enough data

EPA monitors in St John ran on too few days between 2016 and 2025 to give a fair yearly count (about 25% of days covered). Neighbouring counties below are a better guide.

What actually helps here

EPA monitors here ran too few days to give a fair yearly count. Use AirNow for today's air.

The worst days on file

Date	AQI	Main pollutant
2024-04-24	93	PM2.5
2020-09-03	84	PM2.5
2017-05-22	82	PM2.5
2020-06-20	81	PM2.5
2022-05-20	79	PM2.5

An ordinary day in St John

Across 909 monitored days from 2016 to 2025, the air in St John rated Good on 85% of them, more often than the 72% typical of monitored counties, and Moderate on 15%. The median day sat at AQI 22; one day in ten went above 55.

The pollutant setting the AQI on an ordinary day here:

fine particles (PM2.5)100%909 days

Every recent year on file

Year	Days monitored	Good	Moderate	Over 100	Median AQI	Highest AQI
2025*	75	67	8	0	21	75
2024	106	90	16	0	18	93
2023	116	95	21	0	22	71
2022	120	105	15	0	19	79
2021	109	94	15	0	22	69
2020	111	95	16	0	21	84
2019	101	86	15	0	21	77
2018	2	2	0	0	32	32
2017	67	56	11	0	27	82
2016	102	86	16	0	28	69
2015	109	79	30	0	32	74
2014	110	87	23	0	29	80
2013	111	85	26	0	32	87
2012	119	83	36	0	27	98
2011	117	93	24	0	27	80
2010	120	93	26	1	27	108

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

Virgin Islands compared

St Thomasthin data
St Croixthin data

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.