What is the air quality trend in Great Falls?

Over the past 7 days, Great Falls had an average AQI of 25 based on station measurements. The worst day was 2026-10-14 with AQI 40.

How is Great Falls air quality measured?

Air quality in Great Falls 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 Great Falls, United States

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

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

Current AQI
Good Station

48 Hours 7 Days 14 Days 20 Days

CSV JSON

Air Quality Index Station

166h

PM2.5 Station

166h · 20 stations

Temperature GFS model

28pt

Precipitation GFS model

mm/day

Daily Summary Station

Date	AQI	Range	PM2.5 avg	Hours	Stations
2026-10-20	24	19–54	5.9 µg/m³	22h	18
2026-10-19	25	18–32	6.0 µg/m³	24h	22
2026-10-18	18	15–34	4.3 µg/m³	24h	19
2026-10-17	15	11–26	3.7 µg/m³	24h	20
2026-10-16	29	15–48	7.0 µg/m³	24h	20
2026-10-15	29	18–53	7.0 µg/m³	24h	21
2026-10-14	40	35–47	9.6 µg/m³	24h	20

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