EnviroNearby

San Patricio County, Texas air quality history

Daily Air Quality Index summaries from EPA monitors in San Patricio, Texas, 1981–1984.

74%
Good days in 1984
38
Median daily AQI, 1984
3
Days above 100 in 1984
135
Days with an AQI in 1984 (of 366)

In 1984, EPA reported a daily Air Quality Index (AQI) for San Patricio, Texas on 135 days. 100 of those days (74%) were in the Good range, and the median daily AQI was 38. That median is about the same as the typical monitored county in Texas (median 39 across 16 counties), and about the same as the typical monitored U.S. county (40). The main pollutant was ozone on 135 days.

EPA did not report an AQI for every day of 1984 here (135 of 366 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.

The most recent year with data for this county is 1984; EPA's files for 1985–2025 contain no row for it, which usually means its monitors stopped reporting.

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.

Share of monitored days in each AQI category, by year0%25%50%75%100%1981: Good 153 of 193 days1981: Moderate 25 of 193 days1981: Unhealthy for Sensitive Groups 5 of 193 days1981: Unhealthy 8 of 193 days1981: Very Unhealthy 2 of 193 days19811982: Good 205 of 264 days1982: Moderate 37 of 264 days1982: Unhealthy for Sensitive Groups 18 of 264 days1982: Unhealthy 3 of 264 days1982: Very Unhealthy 1 of 264 days19821983: Good 221 of 278 days1983: Moderate 45 of 278 days1983: Unhealthy for Sensitive Groups 11 of 278 days1983: Unhealthy 1 of 278 days19831984: Good 100 of 135 days1984: Moderate 32 of 135 days1984: Unhealthy for Sensitive Groups 2 of 135 days1984: Unhealthy 1 of 135 days1984
  • 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 and 90th-percentile daily AQI, by year0501001981: 90th percentile AQI 901982: 90th percentile AQI 931983: 90th percentile AQI 771984: 90th percentile AQI 671981: Median AQI 321982: Median AQI 371983: Median AQI 371984: Median AQI 381981198219831984
  • Median daily AQI
  • 90th-percentile daily AQI

Main pollutant by day, 1984

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.

PollutantDays as main pollutantShare of monitored days
Ozone135100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
19841351003221003867169Ozone
198327822145111003777164Ozone
198226420537183103793201Ozone
19811931532558203290206Ozone

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 Texas

Source: U.S. EPA AirData, “Annual AQI by County” files for 1981–1984 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem