California · County air quality · 2025

Kings County, California

Median AQI 57 (Moderate). 34.5% of monitored days rated Good, direct from EPA Air Quality System stations.

57
Median AQI
34.5%
Good-air days
0
Unhealthy days
2%
Cleaner than US counties

Kings County's 2025 annual median AQI is 57 (Moderate), with 34.5% Good days

According to the U.S. EPA Air Quality System, Kings County, California posted a 2025 median AQI of 57 (Moderate) across 365 monitored days, with 34.5% rated Good and 0 unhealthy or worse. This is an annual comparison, not today's advisory.

Data source EPA Air Quality System (AQS)

Cleaner than US
Kings County's 34.5% Good-day share places it cleaner than 2% of US counties in 2025.
Closest median-AQI peer
Cameron County (29.9% Good, median AQI 57) is the closest nationwide median-AQI peer to Kings County.
2020–2025 trend
Kings County's floor-qualifying Good-day share is improving from 2020 to 2025 (20.9% → 34.5%).
Median AQI
Median AQI: 57

According to the 2025 EPA AQS county release on PlainAirData, Kings County, California ranks #934 of 951 by median AQI (57) and #928 by good-day share (34.5%). Ponce County, Puerto Rico is #1 of 951 by median AQI (3, 91.4% Good days) at good-day-share #159 ≠ largest of 7 at 100.0% Good days #1 by good-day share (100.0%, median AQI 9) at median-AQI #7.

Annual release change

What changed in the 2025 EPA annual release

2024 → 2025
  • Kings County's Good-day share rose from 27.3% to 34.5% between the 2024 and 2025 EPA annual releases, a change of +7.2 percentage points.
  • Kings County's peak single-day AQI fell from 156 to 133 between the 2024 and 2025 EPA annual releases, a change of -23 points.
  • Kings County's Unhealthy-category days fell from 2 to 0 between the 2024 and 2025 EPA annual releases, a change of -2 days.
  • Kings County's median AQI fell from 60 to 57 between the 2024 and 2025 EPA annual releases, a change of -3 points.

Compared against 366 monitored days in 2024 and 365 in 2025. These are arithmetic differences between two stored EPA annual summaries, not a cause claim or a live advisory.

National release changes Two-year CSV

Data updated August 2026

Kings County AQI category distribution Stacked-segment bar showing the share of monitored days that fell in each EPA AQI category, Good, Moderate, USG, Unhealthy, Very Unhealthy, Hazardous, with median AQI marker. AQI category distribution 365 monitored days G M Median AQI 57 0 50 100 150 200 300 500 Kings County
  • Good · 126 d · 34.5%
  • Moderate · 228 d · 62.5%
  • USG · 11 d · 3.0%

How did Kings County's air break down in 2025?

Across 365 monitored days, 126 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 133 (USG).

EPA AQS →
Kings County, Good days share 34.5%
National avg

Share of monitored days at AQI 0-50 (Good band).

Kings County, Unhealthy-or-worse share 0.0%
National avg

Share of monitored days above AQI 150 (Unhealthy or worse). Bar maxes at 10% (worst-county ceiling).

Where Kings County sits nationally

COUNT-derived placement among 951 US counties with at least 100 monitored days in 2025. Kings County's Good-day share is 34.5% - cleaner than 2% of that comparison set.

Kings County Good-day share vs. every US county

Share of monitored days in the Good band (AQI 0–50) - EPA AQS annual release

34.5% 2nd percentile higher than 2% of 951 US counties

0.0%–5.0%: 0 US counties (0%). Below this entry. 5.0%–10.0%: 1 US counties (0%). Below this entry. 10.0%–15.0%: 4 US counties (0%). Below this entry. 15.0%–20.0%: 4 US counties (0%). Below this entry. 20.0%–25.0%: 1 US counties (0%). Below this entry. 25.0%–30.0%: 5 US counties (1%). Below this entry. 30.0%–35.0%: 9 US counties (1%). This entry sits in this band. 35.0%–40.0%: 4 US counties (0%). Above this entry. 40.0%–45.0%: 16 US counties (2%). Above this entry. 45.0%–50.0%: 16 US counties (2%). Above this entry. 50.0%–55.0%: 32 US counties (3%). Above this entry. 55.0%–60.0%: 50 US counties (5%). Above this entry. 60.0%–65.0%: 77 US counties (8%). Above this entry. 65.0%–70.0%: 93 US counties (10%). Above this entry. 70.0%–75.0%: 109 US counties (11%). Above this entry. 75.0%–80.0%: 114 US counties (12%). Above this entry. 80.0%–85.0%: 123 US counties (13%). Above this entry. 85.0%–90.0%: 99 US counties (10%). Above this entry. 90.0%–95.0%: 117 US counties (12%). Above this entry. 95.0%–100.0%: 70 US counties (7%). Above this entry. 100.0%–105.0%: 7 US counties (1%). Above this entry. This county 0.0% 100% every floor-qualified US county, bucketed by value

Each bar is a band; taller bars hold more US counties. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Source U.S. Environmental Protection Agency, Air Quality System (AQS) · 2025

Pollutant Breakdown

Days where each pollutant was the primary driver of AQI readings in Kings County.

Kings County, California criteria pollutant distribution Stratified-band visualization showing the share of monitored days each criteria pollutant (PM2.5, PM10, O3, NO2, CO) was the primary AQI driver. PM2.5 · 49.9% Ozone · 42.5% 0% 25% 50% 75% 100% Kings County, California · 365 monitored days Criteria pollutant column
  • PM2.5 · 182 days · 49.9%
  • Ozone · 155 days · 42.5%
  • PM10 · 28 days · 7.7%

2024 daily-monitor rhythm in Kings County

Month-by-month median AQI from EPA day-level county monitors (366 reported days in 2024). Jul posted the highest typical readings (median AQI 84, peak 129); Mar was cleanest at median 40. Summer months (Jun–Aug) averaged median AQI 75 vs 56 in Dec–Feb. 2 days crossed Unhealthy (AQI >150) at least once that year.

0 20 40 60 80 100 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 58 41 40 50 53 76 84 64 79 76 61 68
Kings County median daily AQI by calendar month (2024, EPA daily county file)

Five-year seasonal record

EPA day-level county files · 2020–2024

1,827 daily readings show a recurring local pattern: Sep has the highest matched-month median AQI (82), while Mar is lowest (45). Each cell is that month’s median daily AQI, not a current-air forecast.

JanFebMarAprMayJunJulAugSepOctNovDec
2020 65744147505867801161058389
2021 816050515653778084707458
2022 907955475867776670788664
2023 516040474551747061667378
2024 584140505376846479766168

Lower AQI is better. The colors summarize EPA AQI bands; gaps mean the county had no day-level record for that month.

Health Impact Assessment

Poor

Kings County's air quality is rated Poor based on 34.5% good air days. No unhealthy air days were recorded in 2025.

Air quality was acceptable on 34.5% of monitored days in 2025, with a median AQI of 57. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.

The dominant pollutant is PM2.5, driving AQI on 182 of 365 monitored days.

5-Year Air Quality Trend

Air quality is improving in Kings County. Highest Good-day share: 2025 (34.5%, 126 of 365 monitored days).

Year Good Moderate USG Unhealthy Median AQI
2020 76 220 54 13 70
2021 84 230 40 10 64
2022 71 244 48 2 69
2023 124 213 28 0 58
2024 100 231 33 2 60
2025 126 228 11 0 57

How does Kings County compare?

How Kings County compares

Good-day share worse than typical
Kings County 34.5%
Cameron County, Texas 29.9%
Typical US county 76.0%
Median AQI worse than typical
Kings County 57
Cameron County, Texas 57
Typical US county 39
Unhealthy days / yr better than typical
Kings County 0
Cameron County, Texas 0
Typical US county 1

Data Sources

Primary Source: U.S. Environmental Protection Agency (EPA), Air Quality System (AQS), Annual AQI by County dataset, 2020–2025 (aqs.epa.gov). For current conditions (not shown here — this page is historical annual data), see EPA AirNow (airnow.gov). See our methodology for how AQI, median, and coverage figures are computed.

Informational only, not professional advice. Data from EPA AQS. See our disclaimer. Spotted a figure that looks wrong? Report a correction.

Source: U.S. EPA Air Quality System (AQS) Annual AQI by county summary files for Kings County, California · 2020–2025

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Download this county's annual AQI row as CSV , with the same EPA fields and denominator shown on this page.

Every figure on PlainAirData is rendered directly from EPA AQS air-quality monitoring data, no number is typed in by an editor. This page draws directly on EPA AQS air-quality monitoring data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.