SmogRank / Thailand / Prachuap Khiri Khan / Hua Hin

Hua Hin, month by month

Hua Hin has a measured daily mean on 753 days since 1 January 2023. Its worst month was January 2024, at 102 US AQI (36.1 µg/m³), 83rd of 2,385 cities on that month's world ranking. Its cleanest was August 2026, at 39 US AQI (7.1 µg/m³).

Every month since 2023

202661 so far247 days measured599th of 2,791 in the world
Jan83#220Feb68#634Mar65#724Apr75#371May52#794Jun46#1,010Jul3 daysAug39#2,047Sep48#867Oct58#353
2025too few days for a mean (a year needs 256)221 days measured
Jan5 daysFeb80#296Mar87#332Apr70#386May57#576Jun52#1,326JulnoneAug6 daysSep44#1,244Oct10 daysNov12 daysDec75#433
2024too few days for a mean (a year needs 257)196 days measured
Jan102#83Feb85#124Mar16 daysApr82#112May67#193Jun52#788Jul19 daysAug19 daysSep5 daysOct2 daysNov3 daysDecnone
2023too few days for a mean (a year needs 256)89 days measured
Jan100#43Feb2 daysMar9 daysApr19 daysMay14 daysJun10 daysJul6 daysAug3 daysSep3 daysOctnoneNovnoneDecnone
Each square is a month's mean PM2.5 in US AQI from Hua Hin'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 Hua Hin 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

24 months
MonthWhy
Jul 20263 of 31 days measured; a month needs 22. The others: 28 with under 18 hours of readings or readings that failed our checks.
Nov 202512 of 30 days measured; a month needs 21. The others: 18 with under 18 hours of readings or readings that failed our checks.
Oct 202510 of 31 days measured; a month needs 22. The others: 21 with under 18 hours of readings or readings that failed our checks.
Aug 20256 of 31 days measured; a month needs 22. The others: 25 with under 18 hours of readings or readings that failed our checks.
Jul 2025No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Jan 20255 of 31 days measured; a month needs 22. The others: 26 with under 18 hours of readings or readings that failed our checks.
Dec 2024No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Nov 20243 of 30 days measured; a month needs 21. The others: 27 with under 18 hours of readings or readings that failed our checks.
Oct 20242 of 31 days measured; a month needs 22. The others: 29 with under 18 hours of readings or readings that failed our checks.
Sep 20245 of 30 days measured; a month needs 21. The others: 25 with under 18 hours of readings or readings that failed our checks.
Aug 202419 of 31 days measured; a month needs 22. The others: 12 with under 18 hours of readings or readings that failed our checks.
Jul 202419 of 31 days measured; a month needs 22. The others: 12 with under 18 hours of readings or readings that failed our checks.
Mar 202416 of 31 days measured; a month needs 22. The others: 15 with under 18 hours of readings or readings that failed our checks.
Dec 2023No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Nov 2023No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Oct 2023No day measured. The others: 31 with under 18 hours of readings or readings that failed our checks.
Sep 20233 of 30 days measured; a month needs 21. The others: 27 with under 18 hours of readings or readings that failed our checks.
Aug 20233 of 31 days measured; a month needs 22. The others: 28 with under 18 hours of readings or readings that failed our checks.
Jul 20236 of 31 days measured; a month needs 22. The others: 1 missing from OpenAQ's archive, 24 with under 18 hours of readings or readings that failed our checks.
Jun 202310 of 30 days measured; a month needs 21. The others: 20 with under 18 hours of readings or readings that failed our checks.
May 202314 of 31 days measured; a month needs 22. The others: 17 with under 18 hours of readings or readings that failed our checks.
Apr 202319 of 30 days measured; a month needs 21. The others: 2 missing from OpenAQ's archive, 9 with under 18 hours of readings or readings that failed our checks.
Mar 20239 of 31 days measured; a month needs 22. The others: 19 missing from OpenAQ's archive, 3 with under 18 hours of readings or readings that failed our checks.
Feb 20232 of 28 days measured; a month needs 20. The others: 25 missing from OpenAQ's archive, 1 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.

Hua Hin's worst months

MonthUS AQIDays measuredWorld rankEpisode
January 2024 10236.1 µg/m³23 of 3183rdof 2,385–
January 2023 10035.4 µg/m³23 of 3143rdof 1,261Northern Thailand and Laos, January and February 2023
March 2025 8728.5 µg/m³29 of 31332ndof 2,862Thailand and Laos, March 2025
February 2024 8527.1 µg/m³23 of 29124thof 2,486Thailand, February 2024
January 2026 8326.4 µg/m³30 of 31220thof 2,617–
April 2024 8226.0 µg/m³29 of 30112thof 2,520Thailand and Laos, April and May 2024

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.

Hua Hin's worst days

DayUS AQIEpisode
15 Feb 2024 15764.6 µg/m³Thailand, February 2024
16 Apr 2023 15764.3 µg/m³Thailand, April 2023
1 Feb 2023 15460.4 µg/m³Northern Thailand and Laos, January and February 2023
29 Jan 2024 15460.0 µg/m³–
14 Feb 2024 15257.5 µg/m³Thailand, February 2024
13 Feb 2024 14453.0 µg/m³Thailand, February 2024
10 Jan 2023 14151.7 µg/m³–
28 Jan 2024 14151.7 µg/m³–
20 Apr 2023 13750.2 µg/m³Thailand, April 2023
17 Apr 2023 13649.9 µg/m³Thailand, April 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, Hua Hin, Thailand, 1 Jan 2023 – 12 Oct 2026. Monitor data from Air4Thai via OpenAQ; sources listed at smogrank.com/sources. smogrank.com/th/hua-hin/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.

Hua Hin 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).