SmogRank / Switzerland / Lucerne / Sursee

Sursee, month by month

Sursee has a measured daily mean on 461 days since 29 January 2024. Its worst month was August 2025, at 46 US AQI (8.2 µg/m³), 1,750th of 2,901 cities on that month's world ranking. Its cleanest was May 2024, at 17 US AQI (3.1 µg/m³).

Every month since 2024

202629 so far216 days measured2,620th of 2,798 in the world
Jan27#2,354Feb23#2,713Mar44#2,137Apr26#2,592May22#2,666Jun12 daysJul32#2,469Aug32#2,570Sep24#2,649Oct7 days
2025too few days for a mean (a year needs 256)166 days measured
JannoneFebnoneMarnoneAprnoneMay17 daysJun17 daysJul26#2,689Aug46#1,750Sep17 daysOct15 daysNov20 daysDec32#2,530
2024too few days for a mean (a year needs 257)79 days measured
Jan3 daysFeb31#1,956Mar9 daysAprnoneMay17#2,567JunnoneJul8 daysAug4 daysSepnoneOctnoneNov1 dayDec5 days
Each square is a month's mean PM2.5 in US AQI from Sursee'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 Sursee marked; each year, the year's.
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

21 months
MonthWhy
Oct 20267 of 12 days measured; a month needs 9. The others: 1 with no readings from the monitor, 4 with readings for part of the day (a day needs 18 hours).
Jun 202612 of 30 days measured; a month needs 21. The others: 12 with no readings from the monitor, 6 with readings for part of the day (a day needs 18 hours).
Nov 202520 of 30 days measured; a month needs 21. The others: 10 with readings for part of the day (a day needs 18 hours).
Oct 202515 of 31 days measured; a month needs 22. The others: 2 with no readings from the monitor, 14 with readings for part of the day (a day needs 18 hours).
Sep 202517 of 30 days measured; a month needs 21. The others: 3 with no readings from the monitor, 10 with readings for part of the day (a day needs 18 hours).
Jun 202517 of 30 days measured; a month needs 21. The others: 13 with readings for part of the day (a day needs 18 hours).
May 202517 of 31 days measured; a month needs 22. The others: 5 with no readings from the monitor, 9 with readings for part of the day (a day needs 18 hours).
Apr 2025No day measured. The others: 5 with no readings from the monitor, 25 with readings for part of the day (a day needs 18 hours).
Mar 2025No day measured. The others: 3 with no readings from the monitor, 28 with readings for part of the day (a day needs 18 hours).
Feb 2025No day measured. The others: 1 with no readings from the monitor, 27 with readings for part of the day (a day needs 18 hours).
Jan 2025No day measured. The others: 5 with no readings from the monitor, 26 with readings for part of the day (a day needs 18 hours).
Dec 20245 of 31 days measured; a month needs 22. The others: 2 with no readings from the monitor, 24 with readings for part of the day (a day needs 18 hours).
Nov 20241 of 30 days measured; a month needs 21. The others: 29 with readings for part of the day (a day needs 18 hours).
Oct 2024No day measured. The others: 2 with no readings from the monitor, 29 with readings for part of the day (a day needs 18 hours).
Sep 2024No day measured. The others: 9 with no readings from the monitor, 21 with readings for part of the day (a day needs 18 hours).
Aug 20244 of 31 days measured; a month needs 22. The others: 8 with no readings from the monitor, 19 with readings for part of the day (a day needs 18 hours).
Jul 20248 of 31 days measured; a month needs 22. The others: 23 with readings for part of the day (a day needs 18 hours).
Jun 2024No day measured. The others: 23 with no readings from the monitor, 7 with readings for part of the day (a day needs 18 hours).
Apr 2024No day measured. The others: 30 with no readings from the monitor.
Mar 20249 of 31 days measured; a month needs 22. The others: 19 with no readings from the monitor, 3 with readings for part of the day (a day needs 18 hours).
Jan 20243 of 31 days measured; a month needs 22.

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

Sursee's worst months

MonthUS AQIDays measuredWorld rankEpisode
August 2025 468.2 µg/m³23 of 311,750thof 2,901–
March 2026 448.0 µg/m³25 of 312,137thof 2,971Europe, 1 to 12 March 2026
July 2026 325.8 µg/m³24 of 312,469thof 2,784–
December 2025 325.7 µg/m³29 of 312,530thof 3,006–
August 2026 325.7 µg/m³22 of 312,570thof 2,896–
February 2024 315.6 µg/m³27 of 291,956thof 2,486–

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.

Sursee's worst days

DayUS AQIEpisode
7 Mar 2026 8125.4 µg/m³Europe, 1 to 12 March 2026
10 Jun 2025 8125.3 µg/m³Europe, June 2025
29 Feb 2024 7521.8 µg/m³–
11 Jun 2025 7421.7 µg/m³Europe, June 2025
6 Mar 2026 7019.1 µg/m³Europe, 1 to 12 March 2026
16 Aug 2025 6717.8 µg/m³–
28 Feb 2024 6617.2 µg/m³–
19 Mar 2026 6516.7 µg/m³–
12 Aug 2025 6315.7 µg/m³–
21 Mar 2026 6315.7 µg/m³–

Daily means, the highest since 29 Jan 2024; 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, Sursee, Switzerland, 29 Jan 2024 – 10 Oct 2026. Monitor data from EEA, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/ch/sursee/history (accessed 13 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.

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

Updated 2026-10-13 00:07 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).