SmogRank / Countries / United States / Louisiana
Most polluted cities in Louisiana, United States
2 measured cities, last 24 hours; 0 above the WHO 24-hour guideline. Worst: Monroe at 5.3 µg/m³, #877 in the world.
2 good
Good0–9.0
Moderate9.1–35.4
Sensitive groups35.5–55.4
Unhealthy55.5–125.4
Very unhealthy125.5–225.4
Hazardous225.5+
Estimated: cities without a monitor
Louisiana cities we can't measure, with model estimates for the last 7 days. Listed by population, not ranked: estimates aren't precise enough to rank. Model estimates from the Copernicus Atmosphere Monitoring Service (CAMS), adjusted to measured cities nearby where there are any. Adjusted, a single day lands within ×1.5 of what a monitor would read about two times in three; unadjusted, it can be off by half or double. Treat them as a guide, not a measurement.
| City | 7-day estimate |
|---|---|
| Metairie | ≈ 9 µg/m³ |
| Lake Charles | ≈ 7 µg/m³ |
| Bossier City | ≈ 11 µg/m³ |
| Alexandria | ≈ 8 µg/m³ |
| Houma | ≈ 7 µg/m³ |
| Marrero | ≈ 9 µg/m³ |
| New Iberia | ≈ 7 µg/m³ |
| Laplace | ≈ 10 µg/m³ |
| Central | ≈ 12 µg/m³ |
| Slidell | ≈ 8 µg/m³ |
| Prairieville | ≈ 10 µg/m³ |
| Terrytown | ≈ 9 µg/m³ |
| Ruston | ≈ 9 µg/m³ |
| Hammond | ≈ 8 µg/m³ |
| Harvey | ≈ 9 µg/m³ |
| Bayou Cane | ≈ 7 µg/m³ |
| Shenandoah | ≈ 12 µg/m³ |
| Natchitoches | ≈ 12 µg/m³ |
| Gretna | ≈ 9 µg/m³ |
| Opelousas | ≈ 8 µg/m³ |
| Zachary | ≈ 8 µg/m³ |
| Estelle | ≈ 9 µg/m³ |
Updated 2026-10-01 20:07 UTC. Values are PM2.5 in µg/m³ (fine particles), the median of each city's monitors.