SmogRank / United States / Delaware / Glasgow

Glasgow, month by month

Glasgow, Delaware has a measured daily mean on 1,277 days since 1 January 2023. Its worst month was June 2023, at 85 US AQI (27.4 µg/m³), 133rd of 1,603 cities on that month's world ranking. Its cleanest was October 2025, at 21 US AQI (3.7 µg/m³). 2025 averaged 36 US AQI (6.4 µg/m³), against 33 US AQI (6.0 µg/m³) in 2024.

Every month since 2023

Each square is a month's mean PM2.5 in US AQI from Glasgow's measured days, with its place on that month's world ranking under it. A month has a mean once 70% of its days are measured, the rule the monthly rankings use; under that, the square gives the days measured. Each square opens that month's ranking with Glasgow marked; each year, the year's. A dashed square is the running month, so far.
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

Months without a mean, and why

3 months
MonthWhy
Nov 202517 of 30 days measured; a month needs 21. The others: 13 with under 18 hours of readings or readings that failed our checks.
Mar 202311 of 31 days measured; a month needs 22. The others: 20 missing from OpenAQ's archive.
Feb 20233 of 28 days measured; a month needs 20. The others: 25 missing from OpenAQ's archive.

A day counts once 18 hours of it are measured; a month needs 70% of its days.

Glasgow's worst months

MonthUS AQIDays measuredWorld rankEpisode
June 2023 8527.4 µg/m³30 of 30133rdof 1,603Eastern United States and Canada, June and July 2023
Eastern United States and Canada, May and June 2023
July 2026 6114.7 µg/m³31 of 31540thof 2,784Northern United States and Canada, July 2026
July 2023 5511.5 µg/m³30 of 31467thof 1,432United States and Canada, July 2023
Eastern United States and Canada, June and July 2023
February 2026 5310.3 µg/m³28 of 281,328thof 2,866–
November 2023 5310.1 µg/m³24 of 30600thof 2,243–
June 2025 519.3 µg/m³30 of 301,512thof 2,508Northern United States and Canada, June 2025

Monthly means over the days measured; finished months only. World rank: its place on that month's world ranking of every city with enough days. Each month opens that ranking.

Glasgow's worst days

DayUS AQIEpisode
8 Jun 2023 260185.0 µg/m³Eastern United States and Canada, May and June 2023
7 Jun 2023 207132.0 µg/m³Eastern United States and Canada, May and June 2023
17 Jul 2026 198123.0 µg/m³Northern United States and Canada, July 2026
29 Jun 2023 17083.2 µg/m³Eastern United States and Canada, June and July 2023
16 Jul 2026 15662.7 µg/m³Northern United States and Canada, July 2026
30 Jun 2023 14051.3 µg/m³Eastern United States and Canada, June and July 2023
18 Jul 2026 13047.3 µg/m³Northern United States and Canada, July 2026
14 Jun 2025 11641.5 µg/m³Northern United States and Canada, June 2025
5 Nov 2023 10637.6 µg/m³–
6 Jun 2023 9934.7 µg/m³Eastern United States and Canada, May and June 2023

Daily means, the highest since 1 Jan 2023; the WHO's daily guideline is 15 µg/m³. Each date opens that day's world ranking, and each episode the bad-air spell it was part of.

Use this history

SmogRank, PM2.5 monthly and daily means, Glasgow, Delaware, United States, 1 Jan 2023 – 11 Oct 2026. Monitor data from AirNow, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/us/glasgow-delaware/history (accessed 12 Oct 2026).

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You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.

Glasgow now: the last 24 hours, its ranks today and the last 12 months day by day.

Updated 2026-10-12 21:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index. Some low-cost readings: Sensor.Community, ODbL (data and licence). Some readings: Uzhydromet (Uzbekistan's Hydrometeorological Service); Department of Environment, Nepal; Vietnam's government monitors; Aurassure; Umhverfisstofnun (Environment Agency of Iceland); RMCAB (Secretaría Distrital de Ambiente, Bogotá); Love My Air (City and County of Denver), no reuse terms published (why we use them).