Louisiana · County air quality · 2025

Calcasieu County, Louisiana

Median AQI 47 (Good). 62.2% of monitored days rated Good, direct from EPA Air Quality System stations.

47
Median AQI
62.2%
Good-air days
0
Unhealthy days
18%
Cleaner than US counties

Calcasieu County's 2025 annual median AQI is 47 (Good), with 62.2% Good days

According to the U.S. EPA Air Quality System, Calcasieu County, Louisiana posted a 2025 median AQI of 47 (Good) across 365 monitored days, with 62.2% 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
Calcasieu County's 62.2% Good-day share places it cleaner than 18% of US counties in 2025.
Closest median-AQI peer
Bonner County (56.2% Good, median AQI 47) is the closest nationwide median-AQI peer to Calcasieu County.
2020–2025 trend
Calcasieu County's floor-qualifying Good-day share is improving from 2020 to 2025 (51.3% → 62.2%).
Median AQI
Median AQI: 47

According to the 2025 EPA AQS county release on PlainAirData, Calcasieu County, Louisiana ranks #818 of 951 by median AQI (47) and #777 by good-day share (62.2%). 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
  • Calcasieu County's Good-day share rose from 53.0% to 62.2% between the 2024 and 2025 EPA annual releases, a change of +9.2 percentage points.
  • Calcasieu County's peak single-day AQI fell from 147 to 108 between the 2024 and 2025 EPA annual releases, a change of -39 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

Calcasieu 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 47 0 50 100 150 200 300 500 Calcasieu County
  • Good · 227 d · 62.2%
  • Moderate · 135 d · 37.0%
  • USG · 3 d · 0.8%

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

Across 365 monitored days, 227 fell in the Good band (AQI 0–50) and 0 reached Unhealthy or worse. The worst single day peaked at AQI 108 (USG).

EPA AQS →
Calcasieu County, Good days share 62.2%
National avg

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

Calcasieu 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 Calcasieu County sits nationally

COUNT-derived placement among 951 US counties with at least 100 monitored days in 2025. Calcasieu County's Good-day share is 62.2% - cleaner than 18% of that comparison set.

Calcasieu County Good-day share vs. every US county

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

62.2% 18th percentile higher than 18% 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%). Below this entry. 35.0%–40.0%: 4 US counties (0%). Below this entry. 40.0%–45.0%: 16 US counties (2%). Below this entry. 45.0%–50.0%: 16 US counties (2%). Below this entry. 50.0%–55.0%: 32 US counties (3%). Below this entry. 55.0%–60.0%: 50 US counties (5%). Below this entry. 60.0%–65.0%: 77 US counties (8%). This entry sits in this band. 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 Calcasieu County.

Calcasieu County, Louisiana 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 · 62.7% Ozone · 37.3% 0% 25% 50% 75% 100% Calcasieu County, Louisiana · 365 monitored days Criteria pollutant column
  • PM2.5 · 229 days · 62.7%
  • Ozone · 136 days · 37.3%

2024 daily-monitor rhythm in Calcasieu County

Month-by-month median AQI from EPA day-level county monitors (366 reported days in 2024). Feb posted the highest typical readings (median AQI 55, peak 87); Dec was cleanest at median 39. Summer months (Jun–Aug) averaged median AQI 52 vs 46 in Dec–Feb.

0 10 20 30 40 50 60 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 44 55 46 52 53 51 52 54 46 54 41 39
Calcasieu County median daily AQI by calendar month (2024, EPA daily county file)

Five-year seasonal record

EPA day-level county files · 2020–2024

1,810 daily readings show a recurring local pattern: Jun has the highest matched-month median AQI (55), while Dec is lowest (43). Each cell is that month’s median daily AQI, not a current-air forecast.

JanFebMarAprMayJunJulAugSepOctNovDec
2020 434252535256565834364744
2021 475352515054565657464436
2022 465154555456444054554541
2023 404959485857585854424956
2024 445546525351525446544139

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

Moderate

Calcasieu County's air quality is rated Moderate based on 62.2% good air days. No unhealthy air days were recorded in 2025.

Air quality was acceptable on 62.2% of monitored days in 2025, with a median AQI of 47. Unusually sensitive people can check real-time conditions at AirNow.gov during high-pollution events.

The dominant pollutant is PM2.5, driving AQI on 229 of 365 monitored days.

5-Year Air Quality Trend

Air quality is improving in Calcasieu County. Highest Good-day share: 2025 (62.2%, 227 of 365 monitored days).

Year Good Moderate USG Unhealthy Median AQI
2020 179 169 1 0 49
2021 171 193 0 1 51
2022 167 198 0 0 52
2023 139 221 5 0 54
2024 194 168 4 0 49
2025 227 135 3 0 47

How does Calcasieu County compare?

How Calcasieu County compares

Good-day share worse than typical
Calcasieu County 62.2%
Bonner County, Idaho 56.2%
Typical US county 76.0%
Median AQI worse than typical
Calcasieu County 47
Bonner County, Idaho 47
Typical US county 39
Unhealthy days / yr better than typical
Calcasieu County 0
Bonner County, Idaho 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 Calcasieu County, Louisiana · 2020–2025

Embed this widget

Copy this snippet to embed a live-linked card on your own site. Attribution to PlainAirData is baked into the widget.

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.