Bad Air Days in St Croix, Virgin Islands

Not enough data

EPA monitors in St Croix ran on too few days between 2016 and 2025 to give a fair yearly count (about 10% 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
2020-06-20	84	PM2.5
2018-08-06	77	PM2.5
2021-05-16	76	PM2.5
2018-09-29	74	PM2.5
2019-06-20	74	PM2.5

An ordinary day in St Croix

Across 258 monitored days from 2016 to 2022, the air in St Croix rated Good on 81% of them, more often than the 72% typical of monitored counties, and Moderate on 19%. The median day sat at AQI 28; one day in ten went above 59.

The pollutant setting the AQI on an ordinary day here:

fine particles (PM2.5)100%258 days

St Croix by year

Year	Days monitored	Good	Moderate	Median AQI	Highest AQI
2022	26	22	4	29	67
2021	55	46	9	28	76
2020	59	50	9	25	84
2019	57	47	10	27	74
2018	22	16	6	29	77
2017	26	21	5	26	70
2016	13	7	6	44	67
2015	38	16	22	54	88
2014	47	23	24	52	93
2013	25	22	3	23	72
2012	36	27	9	19	59
2011	33	30	3	29	65
2010	58	25	33	53	84

Virgin Islands compared

St Thomasthin data
St Johnthin 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.