St John, Virgin Islands air quality history

Daily Air Quality Index summaries from EPA monitors in St John, Virgin Islands, 1990–2025.

88%

Good days in 2022

Median daily AQI, 2022

Days above 100 in 2022

120

Days with an AQI in 2022 (of 365)

In 2022, EPA reported a daily Air Quality Index (AQI) for St John, Virgin Islands on 120 days. 105 of those days (88%) were in the Good range, and the median daily AQI was 19. That median is lower than the typical monitored U.S. county (41). The main pollutant was fine particles (PM2.5) on 120 days. Across the years with fuller monitoring, the share of Good days fell: an average of 94% in 1998–2000 versus 86% in 2003–2022.

EPA did not report an AQI for every day of 2022 here (120 of 365 days). Figures describe monitored days only; seasonal monitoring (for example, ozone measured only in warmer months) can make a county look cleaner or dirtier than a full-year record would.

Years with fewer than 120 monitored days (2019, 2020, 2021, 2023, 2024, 2025…) are shown in the table but left out of comparisons and trend statements.

How the days broke down each year

Each bar is one year. The colored segments show the share of monitored days that fell in each AQI category.

Good
Moderate
Unhealthy for Sensitive Groups
Unhealthy
Very Unhealthy
Hazardous

Typical and high-end AQI over time

The median is the middle day of the year. The 90th percentile is the level that only the highest 10% of days exceeded.

Median daily AQI
90th-percentile daily AQI

Main pollutant by day, 2022

On each monitored day, the AQI reflects whichever measured pollutant had the highest index. This counts how many days each pollutant set the AQI. A pollutant that was not measured here cannot appear.

Pollutant	Days as main pollutant	Share of monitored days
Fine particles (PM2.5)	120	100%

Year-by-year data

Annual AQI summary by year
Year	Days with AQI	Good	Moderate	Unhealthy for Sensitive Groups	Median AQI	90th pct.	Max AQI	Main pollutant
2025	75	67	8	0	21	51	75	PM2.5
2024	106	90	16	0	18	55	93	PM2.5
2023	116	95	21	0	22	57	71	PM2.5
2022	120	105	15	0	19	59	79	PM2.5
2021	109	94	15	0	22	55	69	PM2.5
2020	111	95	16	0	21	55	84	PM2.5
2019	101	86	15	0	21	54	77	PM2.5
2018	2	2	0	0	32	32	32	PM2.5
2017	67	56	11	0	27	59	82	PM2.5
2016	102	86	16	0	28	53	69	PM2.5
2015	109	79	30	0	32	60	74	PM2.5
2014	110	87	23	0	29	56	80	PM2.5
2013	111	85	26	0	32	60	87	PM2.5
2012	119	83	36	0	27	65	98	PM2.5
2011	117	93	24	0	27	59	80	PM2.5
2010	120	93	26	1	27	62	108	PM2.5
2009	115	96	18	1	22	56	104	PM2.5
2008	113	95	17	1	21	55	108	PM2.5
2007	84	68	14	2	26	57	127	PM2.5
2006	119	92	27	0	27	62	98	PM2.5
2005	111	93	18	0	22	55	97	PM2.5
2004	105	93	12	0	15	52	75	PM2.5
2003	305	286	19	0	26	41	100	Ozone
2002	317	289	28	0	27	46	85	Ozone
2001	330	304	26	0	21	44	87	Ozone
2000	356	342	14	0	26	42	95	Ozone
1999	354	339	15	0	23	39	81	Ozone
1998	214	195	19	0	23	44	77	Ozone
1997	88	54	33	1	42	69	103	PM2.5
1996	41	28	13	0	38	61	73	PM2.5
1995	56	48	8	0	30	56	68	PM2.5
1994	78	56	22	0	32	68	87	PM2.5
1993	97	68	29	0	28	66	82	PM2.5
1992	89	62	27	0	28	66	97	PM2.5
1991	85	68	17	0	28	61	85	PM2.5
1990	18	18	0	0	27	46	47	PM2.5

What this data can and can’t tell you

It is a county-level summary. EPA reports one AQI per day for the county, based on the monitors operating there. Air at a particular street, school or home can differ, especially near roads, industry or wildfire smoke.

It is not a health assessment. The AQI is EPA’s scale for communicating daily air quality. A county’s history can’t tell you what the health risk is for any particular person. For daily conditions and health guidance, see AirNow.

Rules change over time. EPA has revised AQI breakpoints, most recently for fine particles in 2024, so some year-to-year change can reflect the scale rather than the air.

All monitored counties in Virgin Islands

Source: U.S. EPA AirData, “Annual AQI by County” files for 1990–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem