What is the air quality trend in Ellicott City?

Over the past 8 days, Ellicott City had an average AQI of 76 based on station measurements. The worst day was 2026-07-17 with AQI 166.

How is Ellicott City air quality measured?

Air quality in Ellicott City 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 Ellicott City, United States

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

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

Current AQI
Good Station

48 Hours 7 Days 14 Days 20 Days

CSV JSON

Air Quality Index Station

167h

PM2.5 Station

167h · 5 stations

Temperature GFS model

28pt

Precipitation GFS model

mm/day

Daily Summary Station

Date	AQI	Range	PM2.5 avg	Hours	Stations
2026-07-22	27	26–28	6.5 µg/m³	2h	18
2026-07-21	52	30–74	14.3 µg/m³	24h	29
2026-07-20	68	56–82	20.3 µg/m³	24h	27
2026-07-19	60	36–90	17.4 µg/m³	24h	29
2026-07-18	128	59–156	48.3 µg/m³	24h	29
2026-07-17	166	72–232	97.1 µg/m³	24h	31
2026-07-16	61	30–166	18.0 µg/m³	24h	28
2026-07-15	51	40–81	13.1 µg/m³	21h	30

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