SmogRank / Sweden / Västernorrland / Sundsvall

Sundsvall, month by month

Sundsvall has a measured daily mean on 998 days since 11 January 2023. Its worst month was May 2023, at 52 US AQI (9.6 µg/m³), 527th of 1,600 cities on that month's world ranking. Its cleanest was November 2023, at 13 US AQI (2.4 µg/m³). 2025 averaged 27 US AQI (4.8 µg/m³), against 27 US AQI (4.9 µg/m³) in 2024.

Every month since 2023

2026too few days for a mean (a year needs 199)198 days measured
Jan2 daysFeb23#2,713Mar41#2,292Apr27#2,552May27#2,415Jun18 daysJul27#2,617Aug22#2,849Sep18 daysOct27#2,226
202527 for the year260 days measured2,559th of 2,681 in the world
Jan16#2,452Feb26#2,429Mar33#2,302Apr27#2,583May23#2,569Jun17 daysJul44#1,800Aug22#2,816Sep27#2,646Oct19 daysNov19 daysDec8 days
202427 for the year263 days measured1,960th of 2,097 in the world
Jan16#2,354Feb21#2,340Mar15 daysApr33#1,711May44#1,356Jun36#1,911Jul24#2,381Aug15 daysSepnoneOct13 daysNov17#2,571Dec21#2,490
202328 for the year277 days measured1,255th of 1,355 in the world
Jan7 daysFeb16#1,118Mar20 daysApr3 daysMay52#527Jun48#1,008Jul28#1,216Aug26#1,852Sep29#1,938Oct22#1,918Nov13#2,227Dec21#2,150
Each square is a month's mean PM2.5 in US AQI from Sundsvall'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 Sundsvall 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

14 months
MonthWhy
Sep 202618 of 30 days measured; a month needs 21. The others: 1 with no readings from the monitors, 11 with readings for part of the day (a day needs 18 hours).
Jun 202618 of 30 days measured; a month needs 21. The others: 12 with under 18 hours of readings or readings that failed our checks.
Jan 20262 of 31 days measured; a month needs 22. The others: 29 with under 18 hours of readings or readings that failed our checks.
Dec 20258 of 31 days measured; a month needs 22. The others: 23 with under 18 hours of readings or readings that failed our checks.
Nov 202519 of 30 days measured; a month needs 21. The others: 11 with under 18 hours of readings or readings that failed our checks.
Oct 202519 of 31 days measured; a month needs 22. The others: 12 with under 18 hours of readings or readings that failed our checks.
Jun 202517 of 30 days measured; a month needs 21. The others: 13 with under 18 hours of readings or readings that failed our checks.
Oct 202413 of 31 days measured; a month needs 22. The others: 18 with under 18 hours of readings or readings that failed our checks.
Sep 2024No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Aug 202415 of 31 days measured; a month needs 22. The others: 16 with under 18 hours of readings or readings that failed our checks.
Mar 202415 of 31 days measured; a month needs 22. The others: 16 with under 18 hours of readings or readings that failed our checks.
Apr 20233 of 30 days measured; a month needs 21. The others: 27 with under 18 hours of readings or readings that failed our checks.
Mar 202320 of 31 days measured; a month needs 22. The others: 11 with under 18 hours of readings or readings that failed our checks.
Jan 20237 of 31 days measured; a month needs 22. The others: 14 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.

Sundsvall's worst months

MonthUS AQIDays measuredWorld rank
May 2023 529.6 µg/m³25 of 31527thof 1,600
June 2023 488.6 µg/m³30 of 301,008thof 1,603
May 2024 447.9 µg/m³26 of 311,356thof 2,684
July 2025 447.9 µg/m³30 of 311,800thof 2,889
March 2026 417.3 µg/m³27 of 312,292ndof 2,971
June 2024 366.4 µg/m³29 of 301,911thof 2,563

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.

Sundsvall's worst days

DayUS AQI
20 Jun 2023 9030.3 µg/m³
7 Mar 2023 8024.5 µg/m³
21 Jun 2023 7220.6 µg/m³
15 May 2023 7019.3 µg/m³
16 Mar 2026 6717.8 µg/m³
29 May 2024 6717.7 µg/m³
22 Sept 2025 6717.7 µg/m³
5 Jun 2024 6717.5 µg/m³
16 May 2023 6617.2 µg/m³
14 May 2023 6617.0 µg/m³

Daily means, the highest since 11 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, Sundsvall, Sweden, 11 Jan 2023 – 11 Oct 2026. Monitor data from EEA, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/se/sundsvall/history (accessed 12 Oct 2026).

Download chart (PNG)

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.

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

Updated 2026-10-12 20:07 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).