What is the air quality trend in Merrillville?

Over the past 8 days, Merrillville had an average AQI of 31 based on station measurements. The worst day was 2026-10-20 with AQI 53.

How is Merrillville air quality measured?

Air quality in Merrillville is measured by ground-level monitoring stations that report PM2.5 and PM10 concentrations hourly. CERNS.IO aggregates readings from nearby stations and converts PM2.5 to the US EPA Air Quality Index (AQI) scale.

Air Quality History for Merrillville, United States

Name: Merrillville Air Quality History
Creator: CERNS.IO
License: https://creativecommons.org/licenses/by/4.0/

Historical PM2.5 and AQI trend from monitoring stations near Merrillville, United States.

Current AQI
Good Station

48 Hours 7 Days 14 Days 20 Days

CSV JSON

Air Quality Index Station

165h

PM2.5 Station

165h · 214 stations

Temperature GFS model

28pt

Precipitation GFS model

mm/day

Daily Summary Station

Date	AQI	Range	PM2.5 avg	Hours	Stations
2026-10-21	53	52–54	13.1 µg/m³	2h	216
2026-10-20	53	22–73	14.0 µg/m³	24h	191
2026-10-19	28	21–40	6.7 µg/m³	24h	218
2026-10-18	23	18–35	5.4 µg/m³	24h	200
2026-10-17	16	13–23	3.9 µg/m³	24h	217
2026-10-16	20	11–43	4.8 µg/m³	24h	208
2026-10-15	24	14–42	5.8 µg/m³	24h	217
2026-10-14	36	19–52	8.7 µg/m³	19h	217

Back to Merrillville Air Quality