SmogRank / United States / New Hampshire / Laconia
Laconia, month by month
Laconia has a measured daily mean on 1,308 days since 1 January 2023. Its worst month was July 2023, at 53 US AQI (10.0 µg/m³), 663rd of 1,432 cities on that month's world ranking. Its cleanest was May 2025, at 12 US AQI (2.1 µg/m³). 2025 averaged 25 US AQI (4.5 µg/m³), against 27 US AQI (4.8 µg/m³) in 2024.
Every month since 2023
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
2 months
| Month | Why |
|---|---|
| Sep 2024 | 9 of 30 days measured; a month needs 21. The others: 21 with under 18 hours of readings or readings that failed our checks. |
| Aug 2024 | No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks. |
A day counts once 18 hours of it are measured; a month needs 70% of its days.
Laconia's worst months
| Month | US AQI | World rank | Episode |
|---|---|---|---|
| July 2023 | 5310.0 µg/m³ | 663rdof 1,432 | United States and Canada, July 2023 |
| December 2024 | 529.8 µg/m³ | 908thof 2,616 | South-eastern Canada and United States, December 2024 |
| February 2026 | 488.6 µg/m³ | 1,795thof 2,866 | – |
| September 2023 | 417.4 µg/m³ | 1,352ndof 2,176 | North-eastern United States and Canada, September and October 2023 |
| January 2025 | 417.4 µg/m³ | 1,578thof 2,474 | – |
| July 2025 | 386.8 µg/m³ | 2,041stof 2,889 | North-eastern United States and Canada, 29 July to 9 August 2025 North-eastern United States and Canada, 24 to 28 July 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.
Laconia's worst days
| Day | US AQI | Episode |
|---|---|---|
| 18 Jul 2023 | 11039.0 µg/m³ | United States and Canada, July 2023 |
| 26 Jul 2025 | 9230.9 µg/m³ | North-eastern United States and Canada, 24 to 28 July 2025 |
| 30 Sept 2023 | 8929.7 µg/m³ | North-eastern United States and Canada, September and October 2023 |
| 29 Dec 2024 | 8929.4 µg/m³ | South-eastern Canada and United States, December 2024 |
| 4 Aug 2025 | 8829.0 µg/m³ | North-eastern United States and Canada, 29 July to 9 August 2025 |
| 17 Jul 2023 | 8728.4 µg/m³ | United States and Canada, July 2023 |
| 24 Jan 2025 | 8426.7 µg/m³ | – |
| 5 Aug 2025 | 8225.7 µg/m³ | North-eastern United States and Canada, 29 July to 9 August 2025 |
| 22 Jan 2025 | 8125.2 µg/m³ | – |
| 8 Jun 2025 | 8024.7 µg/m³ | – |
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, Laconia, 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/laconia/history (accessed 12 Oct 2026).
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.
Laconia now: the last 24 hours, its ranks today and the last 12 months day by day.
Updated 2026-10-12 23:07 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).