SmogRank / Episodes / Thailand

Central Thailand, March 2025

For 10 days, from 20 to 29 March 2025, 53 cities in Thailand and Laos had PM2.5 at least twice their usual for the time of year. The worst reading was Vientiane, Vientiane Prefecture, Laos: 154.0 µg/m³ on 24 March, about 2.7× its usual 56.3.

No cause namedWe have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached53in 2 countries
Days1020 to 29 March 2025
Worst day24 March42 cities counted
Furthest above usual5.2×Ban Chang

Day by day

24 March 42 cities at twice their usual or more
Lat KrabangBang NaNong ChokBan Khlong PrawetSaphan SungBueng KumKhlong Sam WaKhan Na YaoBan Samae DamSai MaiLak SiSuphan BuriChai NatNakhon SawanSi Sa KetPhichitKalasinAmnat CharoenKamphaeng PhetMukdahanMae SotUttaraditTrangPhraeLampangNanLamphunBetongChiang MaiPhayaoPattaniRoi EtSadaoYasothonKhon KaenKanchanaburiRatchaburiMaha SarakhamNakhon NayokPhetchabunSing BuriHua HinChaiyaphumNakhon RatchasimaUdon ThaniSukhothaiNong Bua LamphuPhra Nakhon Si AyutthayaRanongUbon RatchathaniLop BuriSaraburiSurinBang Bo DistrictPhatthalungSakon NakhonBuri RamNakhon LuangLoeiBang KapiBang PakongSi Maha PhotVientianeLaem ChabangPhra PradaengChumphonPakxanChanthaburiMueang NonthaburiRayongSamut PrakanTratKhlong LuangBangkokNakhon PathomPhetchaburiBan Talat BuengAranyaprathetPrachin BuriNong KhaemSamut SakhonBan PhaeoBan Chang
17 Mar18192021222324252627282930311 Apr
Every measured city in the area, coloured by its PM2.5 that day; a dark ring marks a city at twice its usual or more. Bars: cities counted each day, coloured by their median level. Choose a day or press play; without JavaScript, the days link to that day's world ranking.

How it spread

Ban ChangBan Chang, 17 March: no readingBan Chang, 18 March: 31.1 µg/m³, 1.5× usualBan Chang, 19 March: 45.6 µg/m³, 2.1× usualBan Chang, 20 March: 69.8 µg/m³, 3.3× usualBan Chang, 21 March: 82.7 µg/m³, 3.9× usualBan Chang, 22 March: 89.7 µg/m³, 4.2× usualBan Chang, 23 March: 97.0 µg/m³, 4.6× usualBan Chang, 24 March: 110.0 µg/m³, 5.2× usualBan Chang, 25 March: 78.6 µg/m³, 3.7× usualBan Chang, 26 March: 68.2 µg/m³, 3.2× usualBan Chang, 27 March: 67.2 µg/m³, 3.2× usualBan Chang, 28 March: 70.4 µg/m³, 3.3× usualBan Chang, 29 March: 70.4 µg/m³, 3.3× usualBan Chang, 30 March: 61.3 µg/m³, 2.9× usualBan Chang, 31 March: 40.3 µg/m³, 1.9× usualBan Chang, 1 April: 29.5 µg/m³, 1.4× usualTratTrat, 17 March: 17.4 µg/m³, 0.8× usualTrat, 18 March: 41.4 µg/m³, 2.0× usualTrat, 19 March: 44.9 µg/m³, 2.1× usualTrat, 20 March: 34.4 µg/m³, 1.6× usualTrat, 21 March: 43.0 µg/m³, 2.1× usualTrat, 22 March: 40.2 µg/m³, 1.9× usualTrat, 23 March: 49.9 µg/m³, 2.4× usualTrat, 24 March: 58.4 µg/m³, 2.8× usualTrat, 25 March: 50.6 µg/m³, 2.4× usualTrat, 26 March: 47.7 µg/m³, 2.3× usualTrat, 27 March: no readingTrat, 28 March: no readingTrat, 29 March: 35.4 µg/m³, 1.7× usualTrat, 30 March: 27.9 µg/m³, 1.3× usualTrat, 31 March: 23.7 µg/m³, 1.1× usualTrat, 1 April: 16.8 µg/m³, 0.8× usualNong KhaemNong Khaem, 17 March: 15.2 µg/m³, 0.6× usualNong Khaem, 18 March: 24.3 µg/m³, 1.0× usualNong Khaem, 19 March: 29.8 µg/m³, 1.2× usualNong Khaem, 20 March: 51.2 µg/m³, 2.0× usualNong Khaem, 21 March: 64.8 µg/m³, 2.6× usualNong Khaem, 22 March: 66.1 µg/m³, 2.6× usualNong Khaem, 23 March: 102.0 µg/m³, 4.0× usualNong Khaem, 24 March: 93.7 µg/m³, 3.7× usualNong Khaem, 25 March: 67.6 µg/m³, 2.7× usualNong Khaem, 26 March: 59.8 µg/m³, 2.4× usualNong Khaem, 27 March: 55.6 µg/m³, 2.2× usualNong Khaem, 28 March: 47.2 µg/m³, 1.9× usualNong Khaem, 29 March: 43.1 µg/m³, 1.7× usualNong Khaem, 30 March: 36.2 µg/m³, 1.4× usualNong Khaem, 31 March: 27.3 µg/m³, 1.1× usualNong Khaem, 1 April: 30.4 µg/m³, 1.2× usualBan PhaeoBan Phaeo, 17 March: no readingBan Phaeo, 18 March: no readingBan Phaeo, 19 March: no readingBan Phaeo, 20 March: 44.2 µg/m³, 2.7× usualBan Phaeo, 21 March: 54.1 µg/m³, 3.3× usualBan Phaeo, 22 March: 58.7 µg/m³, 3.6× usualBan Phaeo, 23 March: 69.4 µg/m³, 4.2× usualBan Phaeo, 24 March: 62.3 µg/m³, 3.8× usualBan Phaeo, 25 March: 43.2 µg/m³, 2.6× usualBan Phaeo, 26 March: 43.2 µg/m³, 2.6× usualBan Phaeo, 27 March: 36.8 µg/m³, 2.2× usualBan Phaeo, 28 March: 34.4 µg/m³, 2.1× usualBan Phaeo, 29 March: 38.1 µg/m³, 2.3× usualBan Phaeo, 30 March: 31.6 µg/m³, 1.9× usualBan Phaeo, 31 March: 19.8 µg/m³, 1.2× usualBan Phaeo, 1 April: 16.5 µg/m³, 1.0× usualSamut SakhonSamut Sakhon, 17 March: 10.4 µg/m³, 0.5× usualSamut Sakhon, 18 March: 11.0 µg/m³, 0.6× usualSamut Sakhon, 19 March: 21.0 µg/m³, 1.1× usualSamut Sakhon, 20 March: 42.4 µg/m³, 2.1× usualSamut Sakhon, 21 March: 64.2 µg/m³, 3.2× usualSamut Sakhon, 22 March: 68.8 µg/m³, 3.5× usualSamut Sakhon, 23 March: 82.3 µg/m³, 4.1× usualSamut Sakhon, 24 March: 62.5 µg/m³, 3.1× usualSamut Sakhon, 25 March: 39.9 µg/m³, 2.0× usualSamut Sakhon, 26 March: 39.9 µg/m³, 2.0× usualSamut Sakhon, 27 March: 33.9 µg/m³, 1.7× usualSamut Sakhon, 28 March: 34.3 µg/m³, 1.7× usualSamut Sakhon, 29 March: 38.4 µg/m³, 1.9× usualSamut Sakhon, 30 March: 31.6 µg/m³, 1.6× usualSamut Sakhon, 31 March: 20.1 µg/m³, 1.0× usualSamut Sakhon, 1 April: 18.5 µg/m³, 0.9× usualPhetchaburiPhetchaburi, 17 March: 15.8 µg/m³, 0.7× usualPhetchaburi, 18 March: 14.1 µg/m³, 0.6× usualPhetchaburi, 19 March: 22.9 µg/m³, 1.0× usualPhetchaburi, 20 March: 44.0 µg/m³, 1.8× usualPhetchaburi, 21 March: 64.5 µg/m³, 2.7× usualPhetchaburi, 22 March: 65.2 µg/m³, 2.7× usualPhetchaburi, 23 March: 70.6 µg/m³, 2.9× usualPhetchaburi, 24 March: 62.3 µg/m³, 2.6× usualPhetchaburi, 25 March: 51.2 µg/m³, 2.1× usualPhetchaburi, 26 March: 46.0 µg/m³, 1.9× usualPhetchaburi, 27 March: 39.1 µg/m³, 1.6× usualPhetchaburi, 28 March: 35.9 µg/m³, 1.5× usualPhetchaburi, 29 March: 39.9 µg/m³, 1.7× usualPhetchaburi, 30 March: 33.9 µg/m³, 1.4× usualPhetchaburi, 31 March: 22.9 µg/m³, 1.0× usualPhetchaburi, 1 April: 17.4 µg/m³, 0.7× usualNakhon PathomNakhon Pathom, 17 March: 15.2 µg/m³, 0.6× usualNakhon Pathom, 18 March: 15.5 µg/m³, 0.7× usualNakhon Pathom, 19 March: 29.5 µg/m³, 1.3× usualNakhon Pathom, 20 March: 42.1 µg/m³, 1.8× usualNakhon Pathom, 21 March: 55.8 µg/m³, 2.4× usualNakhon Pathom, 22 March: 59.4 µg/m³, 2.5× usualNakhon Pathom, 23 March: 68.6 µg/m³, 2.9× usualNakhon Pathom, 24 March: 66.5 µg/m³, 2.8× usualNakhon Pathom, 25 March: 52.1 µg/m³, 2.2× usualNakhon Pathom, 26 March: 48.4 µg/m³, 2.1× usualNakhon Pathom, 27 March: 39.6 µg/m³, 1.7× usualNakhon Pathom, 28 March: 38.9 µg/m³, 1.6× usualNakhon Pathom, 29 March: 43.8 µg/m³, 1.9× usualNakhon Pathom, 30 March: 39.8 µg/m³, 1.7× usualNakhon Pathom, 31 March: 24.3 µg/m³, 1.0× usualNakhon Pathom, 1 April: 24.1 µg/m³, 1.0× usualBang Bo DistrictBang Bo District, 17 March: 18.7 µg/m³, 0.8× usualBang Bo District, 18 March: 22.4 µg/m³, 1.0× usualBang Bo District, 19 March: 28.4 µg/m³, 1.3× usualBang Bo District, 20 March: no readingBang Bo District, 21 March: 54.3 µg/m³, 2.4× usualBang Bo District, 22 March: 49.1 µg/m³, 2.2× usualBang Bo District, 23 March: 51.4 µg/m³, 2.3× usualBang Bo District, 24 March: 48.5 µg/m³, 2.2× usualBang Bo District, 25 March: 36.0 µg/m³, 1.6× usualBang Bo District, 26 March: 33.8 µg/m³, 1.5× usualBang Bo District, 27 March: 33.6 µg/m³, 1.5× usualBang Bo District, 28 March: 34.8 µg/m³, 1.6× usualBang Bo District, 29 March: 35.5 µg/m³, 1.6× usualBang Bo District, 30 March: 30.8 µg/m³, 1.4× usualBang Bo District, 31 March: 27.5 µg/m³, 1.2× usualBang Bo District, 1 April: 21.9 µg/m³, 1.0× usualMueang NonthaburiMueang Nonthaburi, 17 March: 16.0 µg/m³, 0.7× usualMueang Nonthaburi, 18 March: 18.9 µg/m³, 0.8× usualMueang Nonthaburi, 19 March: 26.4 µg/m³, 1.2× usualMueang Nonthaburi, 20 March: 37.8 µg/m³, 1.7× usualMueang Nonthaburi, 21 March: 49.3 µg/m³, 2.2× usualMueang Nonthaburi, 22 March: 53.6 µg/m³, 2.4× usualMueang Nonthaburi, 23 March: 60.4 µg/m³, 2.7× usualMueang Nonthaburi, 24 March: 62.5 µg/m³, 2.8× usualMueang Nonthaburi, 25 March: 46.2 µg/m³, 2.0× usualMueang Nonthaburi, 26 March: 40.5 µg/m³, 1.8× usualMueang Nonthaburi, 27 March: 36.8 µg/m³, 1.6× usualMueang Nonthaburi, 28 March: 35.3 µg/m³, 1.6× usualMueang Nonthaburi, 29 March: 33.4 µg/m³, 1.5× usualMueang Nonthaburi, 30 March: 29.7 µg/m³, 1.3× usualMueang Nonthaburi, 31 March: 23.5 µg/m³, 1.0× usualMueang Nonthaburi, 1 April: 20.6 µg/m³, 0.9× usualBangkokBangkok, 17 March: 17.6 µg/m³, 0.8× usualBangkok, 18 March: 20.1 µg/m³, 0.9× usualBangkok, 19 March: 28.4 µg/m³, 1.2× usualBangkok, 20 March: 38.5 µg/m³, 1.7× usualBangkok, 21 March: 47.8 µg/m³, 2.1× usualBangkok, 22 March: 51.5 µg/m³, 2.2× usualBangkok, 23 March: 65.6 µg/m³, 2.8× usualBangkok, 24 March: 67.1 µg/m³, 2.9× usualBangkok, 25 March: 48.1 µg/m³, 2.1× usualBangkok, 26 March: 44.0 µg/m³, 1.9× usualBangkok, 27 March: 41.2 µg/m³, 1.8× usualBangkok, 28 March: 38.1 µg/m³, 1.6× usualBangkok, 29 March: 37.8 µg/m³, 1.6× usualBangkok, 30 March: 34.1 µg/m³, 1.5× usualBangkok, 31 March: 28.8 µg/m³, 1.2× usualBangkok, 1 April: 26.6 µg/m³, 1.2× usualHua HinHua Hin, 17 March: 21.4 µg/m³, 1.0× usualHua Hin, 18 March: 19.9 µg/m³, 0.9× usualHua Hin, 19 March: 21.2 µg/m³, 1.0× usualHua Hin, 20 March: 34.1 µg/m³, 1.6× usualHua Hin, 21 March: 43.3 µg/m³, 2.1× usualHua Hin, 22 March: 45.3 µg/m³, 2.2× usualHua Hin, 23 March: 43.9 µg/m³, 2.1× usualHua Hin, 24 March: 41.5 µg/m³, 2.0× usualHua Hin, 25 March: 37.5 µg/m³, 1.8× usualHua Hin, 26 March: 39.8 µg/m³, 1.9× usualHua Hin, 27 March: 34.6 µg/m³, 1.6× usualHua Hin, 28 March: 28.8 µg/m³, 1.4× usualHua Hin, 29 March: 31.5 µg/m³, 1.5× usualHua Hin, 30 March: 29.3 µg/m³, 1.4× usualHua Hin, 31 March: 24.5 µg/m³, 1.2× usualHua Hin, 1 April: 21.2 µg/m³, 1.0× usualBan Talat BuengBan Talat Bueng, 17 March: 19.6 µg/m³, 0.9× usualBan Talat Bueng, 18 March: 23.7 µg/m³, 1.1× usualBan Talat Bueng, 19 March: 32.3 µg/m³, 1.5× usualBan Talat Bueng, 20 March: 41.2 µg/m³, 1.9× usualBan Talat Bueng, 21 March: 42.7 µg/m³, 2.0× usualBan Talat Bueng, 22 March: 47.4 µg/m³, 2.2× usualBan Talat Bueng, 23 March: 60.3 µg/m³, 2.8× usualBan Talat Bueng, 24 March: 64.4 µg/m³, 3.0× usualBan Talat Bueng, 25 March: 49.7 µg/m³, 2.3× usualBan Talat Bueng, 26 March: 43.7 µg/m³, 2.0× usualBan Talat Bueng, 27 March: 42.8 µg/m³, 2.0× usualBan Talat Bueng, 28 March: 42.6 µg/m³, 2.0× usualBan Talat Bueng, 29 March: 45.4 µg/m³, 2.1× usualBan Talat Bueng, 30 March: 39.3 µg/m³, 1.8× usualBan Talat Bueng, 31 March: 27.4 µg/m³, 1.3× usualBan Talat Bueng, 1 April: 27.8 µg/m³, 1.3× usualChanthaburiChanthaburi, 17 March: 13.5 µg/m³, 0.7× usualChanthaburi, 18 March: 18.3 µg/m³, 1.0× usualChanthaburi, 19 March: 25.9 µg/m³, 1.4× usualChanthaburi, 20 March: 34.7 µg/m³, 1.9× usualChanthaburi, 21 March: 42.3 µg/m³, 2.3× usualChanthaburi, 22 March: 39.4 µg/m³, 2.1× usualChanthaburi, 23 March: 51.2 µg/m³, 2.8× usualChanthaburi, 24 March: 52.9 µg/m³, 2.8× usualChanthaburi, 25 March: 44.3 µg/m³, 2.4× usualChanthaburi, 26 March: 36.9 µg/m³, 2.0× usualChanthaburi, 27 March: 33.9 µg/m³, 1.8× usualChanthaburi, 28 March: 37.2 µg/m³, 2.0× usualChanthaburi, 29 March: 35.9 µg/m³, 1.9× usualChanthaburi, 30 March: 32.1 µg/m³, 1.7× usualChanthaburi, 31 March: 21.8 µg/m³, 1.2× usualChanthaburi, 1 April: 13.5 µg/m³, 0.7× usualSamut PrakanSamut Prakan, 17 March: 12.0 µg/m³, 0.6× usualSamut Prakan, 18 March: 13.5 µg/m³, 0.7× usualSamut Prakan, 19 March: 20.8 µg/m³, 1.1× usualSamut Prakan, 20 March: 35.7 µg/m³, 1.8× usualSamut Prakan, 21 March: 40.7 µg/m³, 2.1× usualSamut Prakan, 22 March: 48.7 µg/m³, 2.5× usualSamut Prakan, 23 March: 54.2 µg/m³, 2.8× usualSamut Prakan, 24 March: 54.6 µg/m³, 2.8× usualSamut Prakan, 25 March: 37.3 µg/m³, 1.9× usualSamut Prakan, 26 March: 33.1 µg/m³, 1.7× usualSamut Prakan, 27 March: 30.8 µg/m³, 1.6× usualSamut Prakan, 28 March: 34.5 µg/m³, 1.8× usualSamut Prakan, 29 March: 35.2 µg/m³, 1.8× usualSamut Prakan, 30 March: 28.8 µg/m³, 1.5× usualSamut Prakan, 31 March: 22.1 µg/m³, 1.1× usualSamut Prakan, 1 April: 17.4 µg/m³, 0.9× usualChumphonChumphon, 17 March: 11.9 µg/m³, 0.8× usualChumphon, 18 March: 13.3 µg/m³, 0.9× usualChumphon, 19 March: 12.4 µg/m³, 0.8× usualChumphon, 20 March: 20.7 µg/m³, 1.4× usualChumphon, 21 March: 39.7 µg/m³, 2.7× usualChumphon, 22 March: 39.7 µg/m³, 2.7× usualChumphon, 23 March: 40.0 µg/m³, 2.7× usualChumphon, 24 March: 37.2 µg/m³, 2.5× usualChumphon, 25 March: 33.8 µg/m³, 2.3× usualChumphon, 26 March: 38.1 µg/m³, 2.6× usualChumphon, 27 March: 29.9 µg/m³, 2.0× usualChumphon, 28 March: 27.1 µg/m³, 1.8× usualChumphon, 29 March: 25.7 µg/m³, 1.7× usualChumphon, 30 March: 25.7 µg/m³, 1.7× usualChumphon, 31 March: 15.9 µg/m³, 1.1× usualChumphon, 1 April: 9.9 µg/m³, 0.7× usualRayongRayong, 17 March: 12.0 µg/m³, 0.6× usualRayong, 18 March: 15.5 µg/m³, 0.8× usualRayong, 19 March: 24.8 µg/m³, 1.3× usualRayong, 20 March: 34.1 µg/m³, 1.8× usualRayong, 21 March: 39.3 µg/m³, 2.1× usualRayong, 22 March: 39.8 µg/m³, 2.2× usualRayong, 23 March: 50.5 µg/m³, 2.7× usualRayong, 24 March: 51.2 µg/m³, 2.8× usualRayong, 25 March: 37.2 µg/m³, 2.0× usualRayong, 26 March: 32.9 µg/m³, 1.8× usualRayong, 27 March: 34.9 µg/m³, 1.9× usualRayong, 28 March: 32.8 µg/m³, 1.8× usualRayong, 29 March: 32.5 µg/m³, 1.8× usualRayong, 30 March: 28.0 µg/m³, 1.5× usualRayong, 31 March: 18.3 µg/m³, 1.0× usualRayong, 1 April: 15.1 µg/m³, 0.8× usualRanongRanong, 17 March: 13.4 µg/m³, 0.8× usualRanong, 18 March: 15.5 µg/m³, 0.9× usualRanong, 19 March: 14.2 µg/m³, 0.8× usualRanong, 20 March: 22.0 µg/m³, 1.3× usualRanong, 21 March: 38.0 µg/m³, 2.2× usualRanong, 22 March: 36.6 µg/m³, 2.1× usualRanong, 23 March: 38.0 µg/m³, 2.2× usualRanong, 24 March: 35.7 µg/m³, 2.1× usualRanong, 25 March: 37.8 µg/m³, 2.2× usualRanong, 26 March: 39.2 µg/m³, 2.3× usualRanong, 27 March: 31.6 µg/m³, 1.8× usualRanong, 28 March: 28.2 µg/m³, 1.6× usualRanong, 29 March: 27.2 µg/m³, 1.6× usualRanong, 30 March: 22.3 µg/m³, 1.3× usualRanong, 31 March: 15.1 µg/m³, 0.9× usualRanong, 1 April: 11.1 µg/m³, 0.6× usualVientianeVientiane, 17 March: 31.2 µg/m³, 0.6× usualVientiane, 18 March: 36.2 µg/m³, 0.6× usualVientiane, 19 March: 52.5 µg/m³, 0.9× usualVientiane, 20 March: 62.9 µg/m³, 1.1× usualVientiane, 21 March: 89.6 µg/m³, 1.6× usualVientiane, 22 March: 111.5 µg/m³, 2.0× usualVientiane, 23 March: 141.5 µg/m³, 2.5× usualVientiane, 24 March: 154.0 µg/m³, 2.7× usualVientiane, 25 March: 150.0 µg/m³, 2.7× usualVientiane, 26 March: 139.5 µg/m³, 2.5× usualVientiane, 27 March: 111.0 µg/m³, 2.0× usualVientiane, 28 March: 107.0 µg/m³, 1.9× usualVientiane, 29 March: 89.2 µg/m³, 1.6× usualVientiane, 30 March: 28.4 µg/m³, 0.5× usualVientiane, 31 March: 42.2 µg/m³, 0.7× usualVientiane, 1 April: 55.1 µg/m³, 1.0× usualKhlong LuangKhlong Luang, 17 March: 23.3 µg/m³, 0.8× usualKhlong Luang, 18 March: 22.7 µg/m³, 0.8× usualKhlong Luang, 19 March: 37.1 µg/m³, 1.3× usualKhlong Luang, 20 March: 46.7 µg/m³, 1.7× usualKhlong Luang, 21 March: 52.4 µg/m³, 1.9× usualKhlong Luang, 22 March: 57.2 µg/m³, 2.0× usualKhlong Luang, 23 March: 75.9 µg/m³, 2.7× usualKhlong Luang, 24 March: 80.1 µg/m³, 2.9× usualKhlong Luang, 25 March: 58.8 µg/m³, 2.1× usualKhlong Luang, 26 March: 49.1 µg/m³, 1.8× usualKhlong Luang, 27 March: 37.9 µg/m³, 1.4× usualKhlong Luang, 28 March: 36.8 µg/m³, 1.3× usualKhlong Luang, 29 March: 38.7 µg/m³, 1.4× usualKhlong Luang, 30 March: no readingKhlong Luang, 31 March: no readingKhlong Luang, 1 April: 25.1 µg/m³, 0.9× usualPhra PradaengPhra Pradaeng, 17 March: 15.7 µg/m³, 0.7× usualPhra Pradaeng, 18 March: 18.5 µg/m³, 0.8× usualPhra Pradaeng, 19 March: 28.0 µg/m³, 1.2× usualPhra Pradaeng, 20 March: 37.1 µg/m³, 1.6× usualPhra Pradaeng, 21 March: 44.5 µg/m³, 1.9× usualPhra Pradaeng, 22 March: 49.9 µg/m³, 2.2× usualPhra Pradaeng, 23 March: 61.8 µg/m³, 2.7× usualPhra Pradaeng, 24 March: 62.4 µg/m³, 2.7× usualPhra Pradaeng, 25 March: 43.8 µg/m³, 1.9× usualPhra Pradaeng, 26 March: 39.8 µg/m³, 1.7× usualPhra Pradaeng, 27 March: 39.0 µg/m³, 1.7× usualPhra Pradaeng, 28 March: 38.9 µg/m³, 1.7× usualPhra Pradaeng, 29 March: 39.3 µg/m³, 1.7× usualPhra Pradaeng, 30 March: 33.8 µg/m³, 1.5× usualPhra Pradaeng, 31 March: 26.3 µg/m³, 1.1× usualPhra Pradaeng, 1 April: 21.6 µg/m³, 0.9× usualLaem ChabangLaem Chabang, 17 March: 16.2 µg/m³, 0.9× usualLaem Chabang, 18 March: 18.2 µg/m³, 1.0× usualLaem Chabang, 19 March: 24.8 µg/m³, 1.3× usualLaem Chabang, 20 March: 33.6 µg/m³, 1.8× usualLaem Chabang, 21 March: 36.5 µg/m³, 1.9× usualLaem Chabang, 22 March: 41.3 µg/m³, 2.2× usualLaem Chabang, 23 March: 50.4 µg/m³, 2.7× usualLaem Chabang, 24 March: no readingLaem Chabang, 25 March: no readingLaem Chabang, 26 March: no readingLaem Chabang, 27 March: no readingLaem Chabang, 28 March: no readingLaem Chabang, 29 March: 38.0 µg/m³, 2.0× usualLaem Chabang, 30 March: 31.4 µg/m³, 1.7× usualLaem Chabang, 31 March: 22.4 µg/m³, 1.2× usualLaem Chabang, 1 April: 19.4 µg/m³, 1.0× usualPattaniPattani, 17 March: 10.3 µg/m³, 0.7× usualPattani, 18 March: 11.9 µg/m³, 0.9× usualPattani, 19 March: 15.9 µg/m³, 1.1× usualPattani, 20 March: 20.8 µg/m³, 1.5× usualPattani, 21 March: 20.9 µg/m³, 1.5× usualPattani, 22 March: 28.0 µg/m³, 2.0× usualPattani, 23 March: 20.3 µg/m³, 1.5× usualPattani, 24 March: 18.4 µg/m³, 1.3× usualPattani, 25 March: 20.8 µg/m³, 1.5× usualPattani, 26 March: 28.5 µg/m³, 2.0× usualPattani, 27 March: 27.4 µg/m³, 2.0× usualPattani, 28 March: 21.0 µg/m³, 1.5× usualPattani, 29 March: 19.2 µg/m³, 1.4× usualPattani, 30 March: 20.6 µg/m³, 1.5× usualPattani, 31 March: 19.1 µg/m³, 1.4× usualPattani, 1 April: 12.1 µg/m³, 0.9× usualPakxanPakxan, 17 March: 23.3 µg/m³, 0.5× usualPakxan, 18 March: 20.6 µg/m³, 0.5× usualPakxan, 19 March: 22.3 µg/m³, 0.5× usualPakxan, 20 March: 27.1 µg/m³, 0.6× usualPakxan, 21 March: 43.4 µg/m³, 1.0× usualPakxan, 22 March: 62.3 µg/m³, 1.4× usualPakxan, 23 March: 101.0 µg/m³, 2.3× usualPakxan, 24 March: 125.0 µg/m³, 2.8× usualPakxan, 25 March: 120.0 µg/m³, 2.7× usualPakxan, 26 March: no readingPakxan, 27 March: no readingPakxan, 28 March: no readingPakxan, 29 March: no readingPakxan, 30 March: no readingPakxan, 31 March: 17.8 µg/m³, 0.4× usualPakxan, 1 April: 51.2 µg/m³, 1.2× usualNong Bua LamphuNong Bua Lamphu, 17 March: 24.4 µg/m³, 0.6× usualNong Bua Lamphu, 18 March: 18.0 µg/m³, 0.5× usualNong Bua Lamphu, 19 March: 26.2 µg/m³, 0.7× usualNong Bua Lamphu, 20 March: 36.6 µg/m³, 0.9× usualNong Bua Lamphu, 21 March: 41.0 µg/m³, 1.1× usualNong Bua Lamphu, 22 March: 55.7 µg/m³, 1.4× usualNong Bua Lamphu, 23 March: 83.0 µg/m³, 2.1× usualNong Bua Lamphu, 24 March: 86.8 µg/m³, 2.2× usualNong Bua Lamphu, 25 March: 88.7 µg/m³, 2.3× usualNong Bua Lamphu, 26 March: 86.4 µg/m³, 2.2× usualNong Bua Lamphu, 27 March: 69.2 µg/m³, 1.8× usualNong Bua Lamphu, 28 March: 72.9 µg/m³, 1.9× usualNong Bua Lamphu, 29 March: 79.4 µg/m³, 2.0× usualNong Bua Lamphu, 30 March: 44.0 µg/m³, 1.1× usualNong Bua Lamphu, 31 March: 13.5 µg/m³, 0.3× usualNong Bua Lamphu, 1 April: 18.1 µg/m³, 0.5× usualBang PakongBang Pakong, 17 March: 25.5 µg/m³, 0.8× usualBang Pakong, 18 March: 38.4 µg/m³, 1.2× usualBang Pakong, 19 March: 42.7 µg/m³, 1.4× usualBang Pakong, 20 March: 51.5 µg/m³, 1.7× usualBang Pakong, 21 March: 55.9 µg/m³, 1.8× usualBang Pakong, 22 March: 58.3 µg/m³, 1.9× usualBang Pakong, 23 March: 80.5 µg/m³, 2.6× usualBang Pakong, 24 March: 70.6 µg/m³, 2.3× usualBang Pakong, 25 March: 52.4 µg/m³, 1.7× usualBang Pakong, 26 March: 47.8 µg/m³, 1.5× usualBang Pakong, 27 March: 49.7 µg/m³, 1.6× usualBang Pakong, 28 March: 49.9 µg/m³, 1.6× usualBang Pakong, 29 March: 49.6 µg/m³, 1.6× usualBang Pakong, 30 March: 39.7 µg/m³, 1.3× usualBang Pakong, 31 March: 35.8 µg/m³, 1.1× usualBang Pakong, 1 April: 39.5 µg/m³, 1.3× usualNakhon LuangNakhon Luang, 17 March: 21.6 µg/m³, 0.7× usualNakhon Luang, 18 March: 24.1 µg/m³, 0.8× usualNakhon Luang, 19 March: 29.2 µg/m³, 1.0× usualNakhon Luang, 20 March: 39.6 µg/m³, 1.3× usualNakhon Luang, 21 March: 47.2 µg/m³, 1.5× usualNakhon Luang, 22 March: 51.1 µg/m³, 1.7× usualNakhon Luang, 23 March: 73.1 µg/m³, 2.4× usualNakhon Luang, 24 March: 76.3 µg/m³, 2.5× usualNakhon Luang, 25 March: 58.1 µg/m³, 1.9× usualNakhon Luang, 26 March: 44.9 µg/m³, 1.5× usualNakhon Luang, 27 March: 39.3 µg/m³, 1.3× usualNakhon Luang, 28 March: 38.7 µg/m³, 1.3× usualNakhon Luang, 29 March: 41.4 µg/m³, 1.4× usualNakhon Luang, 30 March: 33.9 µg/m³, 1.1× usualNakhon Luang, 31 March: 29.0 µg/m³, 1.0× usualNakhon Luang, 1 April: 43.1 µg/m³, 1.4× usualPrachin BuriPrachin Buri, 17 March: 29.6 µg/m³, 1.1× usualPrachin Buri, 18 March: 32.5 µg/m³, 1.2× usualPrachin Buri, 19 March: 30.4 µg/m³, 1.1× usualPrachin Buri, 20 March: 39.2 µg/m³, 1.4× usualPrachin Buri, 21 March: 44.2 µg/m³, 1.6× usualPrachin Buri, 22 March: 50.6 µg/m³, 1.9× usualPrachin Buri, 23 March: 72.8 µg/m³, 2.7× usualPrachin Buri, 24 March: 85.6 µg/m³, 3.2× usualPrachin Buri, 25 March: 67.0 µg/m³, 2.5× usualPrachin Buri, 26 March: 53.9 µg/m³, 2.0× usualPrachin Buri, 27 March: 48.2 µg/m³, 1.8× usualPrachin Buri, 28 March: 46.3 µg/m³, 1.7× usualPrachin Buri, 29 March: 49.4 µg/m³, 1.8× usualPrachin Buri, 30 March: 41.5 µg/m³, 1.5× usualPrachin Buri, 31 March: 29.1 µg/m³, 1.1× usualPrachin Buri, 1 April: 41.9 µg/m³, 1.5× usualAranyaprathetAranyaprathet, 17 March: 18.3 µg/m³, 0.8× usualAranyaprathet, 18 March: 28.7 µg/m³, 1.2× usualAranyaprathet, 19 March: 25.3 µg/m³, 1.1× usualAranyaprathet, 20 March: 35.5 µg/m³, 1.5× usualAranyaprathet, 21 March: 36.4 µg/m³, 1.6× usualAranyaprathet, 22 March: 42.5 µg/m³, 1.8× usualAranyaprathet, 23 March: 69.6 µg/m³, 3.0× usualAranyaprathet, 24 March: 72.4 µg/m³, 3.1× usualAranyaprathet, 25 March: 51.2 µg/m³, 2.2× usualAranyaprathet, 26 March: 38.8 µg/m³, 1.7× usualAranyaprathet, 27 March: 34.1 µg/m³, 1.5× usualAranyaprathet, 28 March: 33.1 µg/m³, 1.4× usualAranyaprathet, 29 March: 33.2 µg/m³, 1.4× usualAranyaprathet, 30 March: 24.8 µg/m³, 1.1× usualAranyaprathet, 31 March: 21.7 µg/m³, 0.9× usualAranyaprathet, 1 April: 25.2 µg/m³, 1.1× usualSurinSurin, 17 March: 26.5 µg/m³, 0.9× usualSurin, 18 March: 24.0 µg/m³, 0.8× usualSurin, 19 March: 26.6 µg/m³, 0.9× usualSurin, 20 March: 40.5 µg/m³, 1.3× usualSurin, 21 March: 39.2 µg/m³, 1.3× usualSurin, 22 March: 49.3 µg/m³, 1.6× usualSurin, 23 March: 65.2 µg/m³, 2.2× usualSurin, 24 March: 69.9 µg/m³, 2.3× usualSurin, 25 March: 73.6 µg/m³, 2.4× usualSurin, 26 March: 62.6 µg/m³, 2.1× usualSurin, 27 March: 47.3 µg/m³, 1.6× usualSurin, 28 March: 41.3 µg/m³, 1.4× usualSurin, 29 March: 38.1 µg/m³, 1.3× usualSurin, 30 March: 29.4 µg/m³, 1.0× usualSurin, 31 March: 20.0 µg/m³, 0.7× usualSurin, 1 April: 20.0 µg/m³, 0.7× usualRatchaburiRatchaburi, 17 March: 22.1 µg/m³, 0.7× usualRatchaburi, 18 March: 20.0 µg/m³, 0.6× usualRatchaburi, 19 March: 29.2 µg/m³, 0.9× usualRatchaburi, 20 March: 48.7 µg/m³, 1.5× usualRatchaburi, 21 March: 59.7 µg/m³, 1.9× usualRatchaburi, 22 March: 60.2 µg/m³, 1.9× usualRatchaburi, 23 March: 63.6 µg/m³, 2.0× usualRatchaburi, 24 March: 67.8 µg/m³, 2.1× usualRatchaburi, 25 March: 57.4 µg/m³, 1.8× usualRatchaburi, 26 March: 55.4 µg/m³, 1.7× usualRatchaburi, 27 March: 45.3 µg/m³, 1.4× usualRatchaburi, 28 March: 41.5 µg/m³, 1.3× usualRatchaburi, 29 March: 45.4 µg/m³, 1.4× usualRatchaburi, 30 March: 42.0 µg/m³, 1.3× usualRatchaburi, 31 March: 29.6 µg/m³, 0.9× usualRatchaburi, 1 April: 23.0 µg/m³, 0.7× usualSi Maha PhotSi Maha Phot, 17 March: 29.8 µg/m³, 1.0× usualSi Maha Phot, 18 March: 32.7 µg/m³, 1.1× usualSi Maha Phot, 19 March: 34.2 µg/m³, 1.1× usualSi Maha Phot, 20 March: 41.5 µg/m³, 1.3× usualSi Maha Phot, 21 March: 44.9 µg/m³, 1.4× usualSi Maha Phot, 22 March: 50.5 µg/m³, 1.6× usualSi Maha Phot, 23 March: 62.9 µg/m³, 2.0× usualSi Maha Phot, 24 March: 80.4 µg/m³, 2.6× usualSi Maha Phot, 25 March: 64.7 µg/m³, 2.1× usualSi Maha Phot, 26 March: 48.9 µg/m³, 1.6× usualSi Maha Phot, 27 March: 48.2 µg/m³, 1.5× usualSi Maha Phot, 28 March: no readingSi Maha Phot, 29 March: no readingSi Maha Phot, 30 March: no readingSi Maha Phot, 31 March: 28.8 µg/m³, 0.9× usualSi Maha Phot, 1 April: 34.9 µg/m³, 1.1× usualPhra Nakhon Si Ayut…Phra Nakhon Si Ayutthaya, 17 March: 18.8 µg/m³, 0.7× usualPhra Nakhon Si Ayutthaya, 18 March: 20.5 µg/m³, 0.8× usualPhra Nakhon Si Ayutthaya, 19 March: 23.9 µg/m³, 0.9× usualPhra Nakhon Si Ayutthaya, 20 March: 39.5 µg/m³, 1.4× usualPhra Nakhon Si Ayutthaya, 21 March: 44.3 µg/m³, 1.6× usualPhra Nakhon Si Ayutthaya, 22 March: 45.7 µg/m³, 1.7× usualPhra Nakhon Si Ayutthaya, 23 March: 60.6 µg/m³, 2.2× usualPhra Nakhon Si Ayutthaya, 24 March: 63.3 µg/m³, 2.3× usualPhra Nakhon Si Ayutthaya, 25 March: 54.3 µg/m³, 2.0× usualPhra Nakhon Si Ayutthaya, 26 March: 46.5 µg/m³, 1.7× usualPhra Nakhon Si Ayutthaya, 27 March: 53.7 µg/m³, 2.0× usualPhra Nakhon Si Ayutthaya, 28 March: 50.9 µg/m³, 1.9× usualPhra Nakhon Si Ayutthaya, 29 March: 60.7 µg/m³, 2.2× usualPhra Nakhon Si Ayutthaya, 30 March: 39.9 µg/m³, 1.5× usualPhra Nakhon Si Ayutthaya, 31 March: 27.3 µg/m³, 1.0× usualPhra Nakhon Si Ayutthaya, 1 April: 39.8 µg/m³, 1.5× usualBang KapiBang Kapi, 17 March: 20.0 µg/m³, 0.8× usualBang Kapi, 18 March: 22.7 µg/m³, 1.0× usualBang Kapi, 19 March: 30.0 µg/m³, 1.3× usualBang Kapi, 20 March: 33.8 µg/m³, 1.4× usualBang Kapi, 21 March: 42.3 µg/m³, 1.8× usualBang Kapi, 22 March: 45.5 µg/m³, 1.9× usualBang Kapi, 23 March: 60.5 µg/m³, 2.5× usualBang Kapi, 24 March: 61.6 µg/m³, 2.6× usualBang Kapi, 25 March: 44.6 µg/m³, 1.9× usualBang Kapi, 26 March: 38.8 µg/m³, 1.6× usualBang Kapi, 27 March: 36.8 µg/m³, 1.5× usualBang Kapi, 28 March: 38.8 µg/m³, 1.6× usualBang Kapi, 29 March: 39.8 µg/m³, 1.7× usualBang Kapi, 30 March: 35.3 µg/m³, 1.5× usualBang Kapi, 31 March: 30.4 µg/m³, 1.3× usualBang Kapi, 1 April: 26.6 µg/m³, 1.1× usualSaraburiSaraburi, 17 March: 19.0 µg/m³, 0.7× usualSaraburi, 18 March: 24.5 µg/m³, 0.9× usualSaraburi, 19 March: 26.8 µg/m³, 1.0× usualSaraburi, 20 March: no readingSaraburi, 21 March: 39.4 µg/m³, 1.4× usualSaraburi, 22 March: 45.3 µg/m³, 1.7× usualSaraburi, 23 March: 56.3 µg/m³, 2.1× usualSaraburi, 24 March: 66.1 µg/m³, 2.4× usualSaraburi, 25 March: 52.9 µg/m³, 1.9× usualSaraburi, 26 March: 44.0 µg/m³, 1.6× usualSaraburi, 27 March: 40.5 µg/m³, 1.5× usualSaraburi, 28 March: 38.5 µg/m³, 1.4× usualSaraburi, 29 March: 37.6 µg/m³, 1.4× usualSaraburi, 30 March: 35.1 µg/m³, 1.3× usualSaraburi, 31 March: 26.9 µg/m³, 1.0× usualSaraburi, 1 April: 31.9 µg/m³, 1.2× usualLoeiLoei, 17 March: 33.7 µg/m³, 0.7× usualLoei, 18 March: 25.9 µg/m³, 0.5× usualLoei, 19 March: 37.4 µg/m³, 0.7× usualLoei, 20 March: 51.8 µg/m³, 1.0× usualLoei, 21 March: 61.1 µg/m³, 1.2× usualLoei, 22 March: 75.1 µg/m³, 1.5× usualLoei, 23 March: 92.4 µg/m³, 1.8× usualLoei, 24 March: 111.0 µg/m³, 2.2× usualLoei, 25 March: 125.0 µg/m³, 2.5× usualLoei, 26 March: 132.0 µg/m³, 2.6× usualLoei, 27 March: 76.1 µg/m³, 1.5× usualLoei, 28 March: 59.4 µg/m³, 1.2× usualLoei, 29 March: 67.1 µg/m³, 1.3× usualLoei, 30 March: 42.9 µg/m³, 0.9× usualLoei, 31 March: 18.0 µg/m³, 0.4× usualLoei, 1 April: 28.0 µg/m³, 0.6× usualSukhothaiSukhothai, 17 March: 44.3 µg/m³, 1.0× usualSukhothai, 18 March: 32.7 µg/m³, 0.8× usualSukhothai, 19 March: 38.3 µg/m³, 0.9× usualSukhothai, 20 March: 53.3 µg/m³, 1.2× usualSukhothai, 21 March: 63.7 µg/m³, 1.5× usualSukhothai, 22 March: 72.5 µg/m³, 1.7× usualSukhothai, 23 March: 81.6 µg/m³, 1.9× usualSukhothai, 24 March: 86.7 µg/m³, 2.0× usualSukhothai, 25 March: 90.7 µg/m³, 2.1× usualSukhothai, 26 March: 99.2 µg/m³, 2.3× usualSukhothai, 27 March: 77.1 µg/m³, 1.8× usualSukhothai, 28 March: 70.0 µg/m³, 1.6× usualSukhothai, 29 March: 98.2 µg/m³, 2.3× usualSukhothai, 30 March: 94.1 µg/m³, 2.2× usualSukhothai, 31 March: 39.6 µg/m³, 0.9× usualSukhothai, 1 April: 34.0 µg/m³, 0.8× usualLop BuriLop Buri, 17 March: 31.3 µg/m³, 0.9× usualLop Buri, 18 March: 35.4 µg/m³, 1.0× usualLop Buri, 19 March: 33.6 µg/m³, 1.0× usualLop Buri, 20 March: 45.3 µg/m³, 1.3× usualLop Buri, 21 March: 49.0 µg/m³, 1.4× usualLop Buri, 22 March: 50.3 µg/m³, 1.5× usualLop Buri, 23 March: 64.8 µg/m³, 1.9× usualLop Buri, 24 March: 82.1 µg/m³, 2.4× usualLop Buri, 25 March: 72.1 µg/m³, 2.1× usualLop Buri, 26 March: 59.3 µg/m³, 1.7× usualLop Buri, 27 March: 52.3 µg/m³, 1.5× usualLop Buri, 28 March: 49.1 µg/m³, 1.4× usualLop Buri, 29 March: 50.3 µg/m³, 1.5× usualLop Buri, 30 March: 44.3 µg/m³, 1.3× usualLop Buri, 31 March: 29.9 µg/m³, 0.9× usualLop Buri, 1 April: 47.8 µg/m³, 1.4× usualPhetchabunPhetchabun, 17 March: 25.8 µg/m³, 0.7× usualPhetchabun, 18 March: 29.8 µg/m³, 0.8× usualPhetchabun, 19 March: 32.0 µg/m³, 0.9× usualPhetchabun, 20 March: 44.9 µg/m³, 1.2× usualPhetchabun, 21 March: 56.9 µg/m³, 1.6× usualPhetchabun, 22 March: 64.8 µg/m³, 1.8× usualPhetchabun, 23 March: 71.6 µg/m³, 2.0× usualPhetchabun, 24 March: 81.9 µg/m³, 2.2× usualPhetchabun, 25 March: 79.5 µg/m³, 2.2× usualPhetchabun, 26 March: 69.6 µg/m³, 1.9× usualPhetchabun, 27 March: 58.3 µg/m³, 1.6× usualPhetchabun, 28 March: 56.1 µg/m³, 1.5× usualPhetchabun, 29 March: 53.6 µg/m³, 1.5× usualPhetchabun, 30 March: 50.5 µg/m³, 1.4× usualPhetchabun, 31 March: 36.3 µg/m³, 1.0× usualPhetchabun, 1 April: 30.8 µg/m³, 0.8× usualSing BuriSing Buri, 17 March: 31.3 µg/m³, 0.8× usualSing Buri, 18 March: 28.1 µg/m³, 0.8× usualSing Buri, 19 March: 32.9 µg/m³, 0.9× usualSing Buri, 20 March: 43.6 µg/m³, 1.2× usualSing Buri, 21 March: 49.5 µg/m³, 1.3× usualSing Buri, 22 March: 55.8 µg/m³, 1.5× usualSing Buri, 23 March: 73.1 µg/m³, 2.0× usualSing Buri, 24 March: 81.8 µg/m³, 2.2× usualSing Buri, 25 March: 67.8 µg/m³, 1.8× usualSing Buri, 26 March: 55.4 µg/m³, 1.5× usualSing Buri, 27 March: 48.8 µg/m³, 1.3× usualSing Buri, 28 March: 45.7 µg/m³, 1.2× usualSing Buri, 29 March: 51.4 µg/m³, 1.4× usualSing Buri, 30 March: 50.0 µg/m³, 1.3× usualSing Buri, 31 March: 30.7 µg/m³, 0.8× usualSing Buri, 1 April: 49.6 µg/m³, 1.3× usualChaiyaphumChaiyaphum, 17 March: 20.8 µg/m³, 0.6× usualChaiyaphum, 18 March: 26.8 µg/m³, 0.7× usualChaiyaphum, 19 March: 27.9 µg/m³, 0.8× usualChaiyaphum, 20 March: 40.3 µg/m³, 1.1× usualChaiyaphum, 21 March: 41.7 µg/m³, 1.1× usualChaiyaphum, 22 March: 44.2 µg/m³, 1.2× usualChaiyaphum, 23 March: 56.3 µg/m³, 1.5× usualChaiyaphum, 24 March: 78.8 µg/m³, 2.1× usualChaiyaphum, 25 March: 84.2 µg/m³, 2.3× usualChaiyaphum, 26 March: 71.2 µg/m³, 1.9× usualChaiyaphum, 27 March: 60.8 µg/m³, 1.6× usualChaiyaphum, 28 March: 56.1 µg/m³, 1.5× usualChaiyaphum, 29 March: 51.9 µg/m³, 1.4× usualChaiyaphum, 30 March: 39.9 µg/m³, 1.1× usualChaiyaphum, 31 March: 20.9 µg/m³, 0.6× usualChaiyaphum, 1 April: 22.4 µg/m³, 0.6× usualNakhon RatchasimaNakhon Ratchasima, 17 March: 27.0 µg/m³, 0.8× usualNakhon Ratchasima, 18 March: 29.4 µg/m³, 0.9× usualNakhon Ratchasima, 19 March: 27.4 µg/m³, 0.8× usualNakhon Ratchasima, 20 March: 43.1 µg/m³, 1.3× usualNakhon Ratchasima, 21 March: 49.7 µg/m³, 1.5× usualNakhon Ratchasima, 22 March: 45.8 µg/m³, 1.4× usualNakhon Ratchasima, 23 March: 63.0 µg/m³, 1.9× usualNakhon Ratchasima, 24 March: 77.7 µg/m³, 2.3× usualNakhon Ratchasima, 25 March: 76.2 µg/m³, 2.3× usualNakhon Ratchasima, 26 March: 62.0 µg/m³, 1.8× usualNakhon Ratchasima, 27 March: 57.0 µg/m³, 1.7× usualNakhon Ratchasima, 28 March: 50.8 µg/m³, 1.5× usualNakhon Ratchasima, 29 March: 43.1 µg/m³, 1.3× usualNakhon Ratchasima, 30 March: 38.3 µg/m³, 1.1× usualNakhon Ratchasima, 31 March: 25.3 µg/m³, 0.8× usualNakhon Ratchasima, 1 April: 25.5 µg/m³, 0.8× usualUdon ThaniUdon Thani, 17 March: 21.3 µg/m³, 0.6× usualUdon Thani, 18 March: 15.3 µg/m³, 0.4× usualUdon Thani, 19 March: 25.3 µg/m³, 0.7× usualUdon Thani, 20 March: 33.6 µg/m³, 0.9× usualUdon Thani, 21 March: 40.0 µg/m³, 1.0× usualUdon Thani, 22 March: 45.2 µg/m³, 1.2× usualUdon Thani, 23 March: 62.4 µg/m³, 1.6× usualUdon Thani, 24 March: 76.5 µg/m³, 2.0× usualUdon Thani, 25 March: 86.7 µg/m³, 2.3× usualUdon Thani, 26 March: 79.9 µg/m³, 2.1× usualUdon Thani, 27 March: 70.4 µg/m³, 1.8× usualUdon Thani, 28 March: 58.2 µg/m³, 1.5× usualUdon Thani, 29 March: 53.2 µg/m³, 1.4× usualUdon Thani, 30 March: 32.0 µg/m³, 0.8× usualUdon Thani, 31 March: 13.1 µg/m³, 0.3× usualUdon Thani, 1 April: 14.2 µg/m³, 0.4× usualMaha SarakhamMaha Sarakham, 17 March: 21.8 µg/m³, 0.6× usualMaha Sarakham, 18 March: 24.3 µg/m³, 0.7× usualMaha Sarakham, 19 March: 31.9 µg/m³, 0.9× usualMaha Sarakham, 20 March: 43.0 µg/m³, 1.2× usualMaha Sarakham, 21 March: 42.7 µg/m³, 1.2× usualMaha Sarakham, 22 March: 46.3 µg/m³, 1.3× usualMaha Sarakham, 23 March: 57.5 µg/m³, 1.6× usualMaha Sarakham, 24 March: 72.5 µg/m³, 2.0× usualMaha Sarakham, 25 March: 78.6 µg/m³, 2.2× usualMaha Sarakham, 26 March: 73.9 µg/m³, 2.0× usualMaha Sarakham, 27 March: 62.3 µg/m³, 1.7× usualMaha Sarakham, 28 March: 54.8 µg/m³, 1.5× usualMaha Sarakham, 29 March: 53.0 µg/m³, 1.5× usualMaha Sarakham, 30 March: 34.0 µg/m³, 0.9× usualMaha Sarakham, 31 March: no readingMaha Sarakham, 1 April: no readingKanchanaburiKanchanaburi, 17 March: 26.8 µg/m³, 0.8× usualKanchanaburi, 18 March: 27.2 µg/m³, 0.9× usualKanchanaburi, 19 March: 34.9 µg/m³, 1.1× usualKanchanaburi, 20 March: 38.6 µg/m³, 1.2× usualKanchanaburi, 21 March: 52.8 µg/m³, 1.7× usualKanchanaburi, 22 March: 49.7 µg/m³, 1.6× usualKanchanaburi, 23 March: 56.5 µg/m³, 1.8× usualKanchanaburi, 24 March: 65.1 µg/m³, 2.1× usualKanchanaburi, 25 March: 61.7 µg/m³, 1.9× usualKanchanaburi, 26 March: 50.3 µg/m³, 1.6× usualKanchanaburi, 27 March: 49.4 µg/m³, 1.6× usualKanchanaburi, 28 March: 43.9 µg/m³, 1.4× usualKanchanaburi, 29 March: 46.1 µg/m³, 1.5× usualKanchanaburi, 30 March: no readingKanchanaburi, 31 March: no readingKanchanaburi, 1 April: 40.1 µg/m³, 1.3× usualNakhon NayokNakhon Nayok, 17 March: 15.7 µg/m³, 0.7× usualNakhon Nayok, 18 March: 21.3 µg/m³, 0.9× usualNakhon Nayok, 19 March: 16.8 µg/m³, 0.7× usualNakhon Nayok, 20 March: 22.0 µg/m³, 0.9× usualNakhon Nayok, 21 March: 28.3 µg/m³, 1.2× usualNakhon Nayok, 22 March: 31.0 µg/m³, 1.3× usualNakhon Nayok, 23 March: 39.0 µg/m³, 1.7× usualNakhon Nayok, 24 March: 50.4 µg/m³, 2.1× usualNakhon Nayok, 25 March: 51.7 µg/m³, 2.2× usualNakhon Nayok, 26 March: 51.4 µg/m³, 2.2× usualNakhon Nayok, 27 March: 42.5 µg/m³, 1.8× usualNakhon Nayok, 28 March: 44.0 µg/m³, 1.9× usualNakhon Nayok, 29 March: 32.5 µg/m³, 1.4× usualNakhon Nayok, 30 March: 35.7 µg/m³, 1.5× usualNakhon Nayok, 31 March: 24.0 µg/m³, 1.0× usualNakhon Nayok, 1 April: 24.9 µg/m³, 1.1× usualKhon KaenKhon Kaen, 17 March: 31.4 µg/m³, 0.7× usualKhon Kaen, 18 March: 33.8 µg/m³, 0.8× usualKhon Kaen, 19 March: 38.9 µg/m³, 0.9× usualKhon Kaen, 20 March: 51.3 µg/m³, 1.2× usualKhon Kaen, 21 March: 51.8 µg/m³, 1.2× usualKhon Kaen, 22 March: no readingKhon Kaen, 23 March: no readingKhon Kaen, 24 March: no readingKhon Kaen, 25 March: 91.6 µg/m³, 2.1× usualKhon Kaen, 26 March: 89.9 µg/m³, 2.1× usualKhon Kaen, 27 March: 76.4 µg/m³, 1.8× usualKhon Kaen, 28 March: no readingKhon Kaen, 29 March: no readingKhon Kaen, 30 March: 37.8 µg/m³, 0.9× usualKhon Kaen, 31 March: 23.6 µg/m³, 0.5× usualKhon Kaen, 1 April: 28.7 µg/m³, 0.7× usualRoi EtRoi Et, 17 March: 21.1 µg/m³, 0.5× usualRoi Et, 18 March: 20.5 µg/m³, 0.5× usualRoi Et, 19 March: 32.1 µg/m³, 0.7× usualRoi Et, 20 March: 50.2 µg/m³, 1.2× usualRoi Et, 21 March: 43.2 µg/m³, 1.0× usualRoi Et, 22 March: 46.4 µg/m³, 1.1× usualRoi Et, 23 March: 56.9 µg/m³, 1.3× usualRoi Et, 24 March: 74.8 µg/m³, 1.7× usualRoi Et, 25 March: 87.2 µg/m³, 2.0× usualRoi Et, 26 March: 83.4 µg/m³, 1.9× usualRoi Et, 27 March: 68.3 µg/m³, 1.6× usualRoi Et, 28 March: 58.5 µg/m³, 1.4× usualRoi Et, 29 March: 55.1 µg/m³, 1.3× usualRoi Et, 30 March: 30.1 µg/m³, 0.7× usualRoi Et, 31 March: 15.5 µg/m³, 0.4× usualRoi Et, 1 April: 18.7 µg/m³, 0.4× usualBuri RamBuri Ram, 17 March: 26.4 µg/m³, 0.9× usualBuri Ram, 18 March: 24.2 µg/m³, 0.8× usualBuri Ram, 19 March: 25.9 µg/m³, 0.9× usualBuri Ram, 20 March: 41.2 µg/m³, 1.4× usualBuri Ram, 21 March: 41.4 µg/m³, 1.4× usualBuri Ram, 22 March: 49.9 µg/m³, 1.7× usualBuri Ram, 23 March: no readingBuri Ram, 24 March: no readingBuri Ram, 25 March: 74.5 µg/m³, 2.5× usualBuri Ram, 26 March: 63.3 µg/m³, 2.2× usualBuri Ram, 27 March: 48.7 µg/m³, 1.7× usualBuri Ram, 28 March: 42.2 µg/m³, 1.4× usualBuri Ram, 29 March: 40.4 µg/m³, 1.4× usualBuri Ram, 30 March: 32.3 µg/m³, 1.1× usualBuri Ram, 31 March: 20.9 µg/m³, 0.7× usualBuri Ram, 1 April: 22.3 µg/m³, 0.8× usualUbon RatchathaniUbon Ratchathani, 17 March: 40.3 µg/m³, 0.7× usualUbon Ratchathani, 18 March: 19.2 µg/m³, 0.3× usualUbon Ratchathani, 19 March: 21.9 µg/m³, 0.4× usualUbon Ratchathani, 20 March: 35.0 µg/m³, 0.6× usualUbon Ratchathani, 21 March: 38.1 µg/m³, 0.7× usualUbon Ratchathani, 22 March: 55.9 µg/m³, 1.0× usualUbon Ratchathani, 23 March: 64.3 µg/m³, 1.2× usualUbon Ratchathani, 24 March: 80.0 µg/m³, 1.5× usualUbon Ratchathani, 25 March: 109.0 µg/m³, 2.0× usualUbon Ratchathani, 26 March: 133.0 µg/m³, 2.4× usualUbon Ratchathani, 27 March: 126.0 µg/m³, 2.3× usualUbon Ratchathani, 28 March: 109.0 µg/m³, 2.0× usualUbon Ratchathani, 29 March: 112.0 µg/m³, 2.0× usualUbon Ratchathani, 30 March: 59.1 µg/m³, 1.1× usualUbon Ratchathani, 31 March: 18.6 µg/m³, 0.3× usualUbon Ratchathani, 1 April: 18.4 µg/m³, 0.3× usualSakon NakhonSakon Nakhon, 17 March: 16.7 µg/m³, 0.5× usualSakon Nakhon, 18 March: 16.3 µg/m³, 0.4× usualSakon Nakhon, 19 March: 31.9 µg/m³, 0.9× usualSakon Nakhon, 20 March: 36.9 µg/m³, 1.0× usualSakon Nakhon, 21 March: 36.5 µg/m³, 1.0× usualSakon Nakhon, 22 March: 41.1 µg/m³, 1.1× usualSakon Nakhon, 23 March: 39.9 µg/m³, 1.1× usualSakon Nakhon, 24 March: 49.4 µg/m³, 1.3× usualSakon Nakhon, 25 March: 68.0 µg/m³, 1.8× usualSakon Nakhon, 26 March: 92.4 µg/m³, 2.5× usualSakon Nakhon, 27 March: 78.5 µg/m³, 2.1× usualSakon Nakhon, 28 March: 70.4 µg/m³, 1.9× usualSakon Nakhon, 29 March: 60.5 µg/m³, 1.6× usualSakon Nakhon, 30 March: 27.0 µg/m³, 0.7× usualSakon Nakhon, 31 March: 10.2 µg/m³, 0.3× usualSakon Nakhon, 1 April: 12.1 µg/m³, 0.3× usualYasothonYasothon, 17 March: 31.0 µg/m³, 0.7× usualYasothon, 18 March: 27.2 µg/m³, 0.6× usualYasothon, 19 March: 34.7 µg/m³, 0.8× usualYasothon, 20 March: 46.6 µg/m³, 1.1× usualYasothon, 21 March: 44.2 µg/m³, 1.1× usualYasothon, 22 March: 49.8 µg/m³, 1.2× usualYasothon, 23 March: 56.9 µg/m³, 1.4× usualYasothon, 24 March: 67.1 µg/m³, 1.6× usualYasothon, 25 March: 77.3 µg/m³, 1.8× usualYasothon, 26 March: 86.4 µg/m³, 2.1× usualYasothon, 27 March: 76.1 µg/m³, 1.8× usualYasothon, 28 March: 64.2 µg/m³, 1.5× usualYasothon, 29 March: 68.2 µg/m³, 1.6× usualYasothon, 30 March: 40.0 µg/m³, 1.0× usualYasothon, 31 March: 26.8 µg/m³, 0.6× usualYasothon, 1 April: 27.8 µg/m³, 0.7× usualPhatthalungPhatthalung, 17 March: 18.6 µg/m³, 1.4× usualPhatthalung, 18 March: 11.9 µg/m³, 0.9× usualPhatthalung, 19 March: 14.6 µg/m³, 1.1× usualPhatthalung, 20 March: 17.5 µg/m³, 1.3× usualPhatthalung, 21 March: 18.1 µg/m³, 1.4× usualPhatthalung, 22 March: 26.7 µg/m³, 2.0× usualPhatthalung, 23 March: 23.1 µg/m³, 1.8× usualPhatthalung, 24 March: 17.8 µg/m³, 1.3× usualPhatthalung, 25 March: 23.8 µg/m³, 1.8× usualPhatthalung, 26 March: 32.5 µg/m³, 2.5× usualPhatthalung, 27 March: 27.9 µg/m³, 2.1× usualPhatthalung, 28 March: 21.7 µg/m³, 1.6× usualPhatthalung, 29 March: 20.9 µg/m³, 1.6× usualPhatthalung, 30 March: 21.8 µg/m³, 1.7× usualPhatthalung, 31 March: 18.9 µg/m³, 1.4× usualPhatthalung, 1 April: 14.0 µg/m³, 1.1× usualSadaoSadao, 17 March: 14.6 µg/m³, 1.0× usualSadao, 18 March: 12.3 µg/m³, 0.8× usualSadao, 19 March: 17.4 µg/m³, 1.2× usualSadao, 20 March: 21.3 µg/m³, 1.4× usualSadao, 21 March: 22.1 µg/m³, 1.5× usualSadao, 22 March: 29.8 µg/m³, 2.0× usualSadao, 23 March: 23.2 µg/m³, 1.5× usualSadao, 24 March: 18.7 µg/m³, 1.2× usualSadao, 25 March: 22.2 µg/m³, 1.5× usualSadao, 26 March: 32.1 µg/m³, 2.1× usualSadao, 27 March: 30.2 µg/m³, 2.0× usualSadao, 28 March: 26.4 µg/m³, 1.7× usualSadao, 29 March: 29.3 µg/m³, 1.9× usualSadao, 30 March: 22.3 µg/m³, 1.5× usualSadao, 31 March: 20.9 µg/m³, 1.4× usualSadao, 1 April: 16.4 µg/m³, 1.1× usual17 Mar192123252729311 Apr
Every counted city, in the order the episode reached them, 3 days before to 3 after. Each square is a day, coloured by that day's PM2.5; outlined: at twice the city's usual or more.
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

Every city it reached

CityDaysHighestUsualAbove usual
Ban ChangRayong, Thailand10 110.024 March21.35.2×
Ban PhaeoSamut Sakhon, Thailand10 69.423 March16.44.2×
Samut SakhonSamut Sakhon, Thailand5 82.323 March19.94.1×
Nong KhaemBangkok, Thailand8 102.023 March25.34.0×
Prachin BuriPrachin Buri, Thailand4 85.624 March27.13.2×
AranyaprathetSa Kaeo, Thailand3 72.424 March23.03.1×
Ban Talat BuengChon Buri, Thailand9 64.424 March21.63.0×
PhetchaburiPhetchaburi, Thailand5 70.623 March24.02.9×
Nakhon PathomNakhon Pathom, Thailand6 68.623 March23.62.9×
BangkokBangkok, Thailand5 67.124 March23.12.9×
Khlong LuangPathum Thani, Thailand4 80.124 March28.02.9×
PakxanBolikhamsai, Laos3 125.024 March43.92.8×
ChanthaburiChanthaburi, Thailand6 52.924 March18.62.8×
TratTrat, Thailand5 58.424 March20.92.8×
Samut PrakanSamut Prakan, Thailand4 54.624 March19.62.8×
RayongRayong, Thailand5 51.224 March18.52.8×
Mueang NonthaburiNonthaburi, Thailand5 62.524 March22.62.8×
VientianeVientiane Prefecture, Laos4 154.024 March56.32.7×
Phra PradaengSamut Prakan, Thailand3 62.424 March22.92.7×
ChumphonChumphon, Thailand7 40.023 March14.92.7×
Laem ChabangChon Buri, Thailand3 50.423 March18.92.7×
LoeiLoei, Thailand3 132.026 March50.12.6×
Bang KapiBangkok, Thailand2 61.624 March23.82.6×
Si Maha PhotPrachin Buri, Thailand3 80.424 March31.12.6×
Bang PakongChachoengsao, Thailand2 80.523 March31.22.6×
Buri RamBuriram, Thailand2 74.525 March29.32.5×
Sakon NakhonSakon Nakhon, Thailand1 92.426 March36.92.5×
Nakhon LuangPhra Nakhon Si Ayutthaya, Thailand2 76.324 March30.52.5×
PhatthalungPhatthalung, Thailand2 32.526 March13.22.5×
Bang Bo DistrictSamut Prakan, Thailand4 54.321 March22.22.4×
SurinSurin, Thailand4 73.625 March30.12.4×
SaraburiSaraburi, Thailand2 66.124 March27.22.4×
Ubon RatchathaniUbon Ratchathani, Thailand2 133.026 March55.02.4×
Lop BuriLopburi, Thailand2 82.124 March34.42.4×
Phra Nakhon Si AyutthayaPhra Nakhon Si Ayutthaya, Thailand3 63.324 March27.32.3×
Nakhon RatchasimaNakhon Ratchasima, Thailand2 77.724 March33.62.3×
SukhothaiSukhothai, Thailand4 99.226 March43.22.3×
Nong Bua LamphuNong Bua Lamphu, Thailand5 88.725 March38.82.3×
ChaiyaphumChaiyaphum, Thailand2 84.225 March37.02.3×
Udon ThaniUdon Thani, Thailand3 86.725 March38.42.3×
RanongRanong province, Thailand6 39.226 March17.42.3×
PhetchabunPhetchabun, Thailand2 81.924 March36.72.2×
Sing BuriSing Buri, Thailand1 81.824 March37.32.2×
Nakhon NayokNakhon Nayok, Thailand3 51.725 March23.62.2×
Maha SarakhamMaha Sarakham, Thailand3 78.625 March36.42.2×
Hua HinPrachuap Khiri Khan, Thailand3 45.322 March21.02.2×
RatchaburiRatchaburi, Thailand2 67.824 March31.82.1×
SadaoSongkhla, Thailand2 32.126 March15.12.1×
Khon KaenKhon Kaen, Thailand2 91.625 March43.22.1×
YasothonYasothon, Thailand1 86.426 March41.92.1×
KanchanaburiKanchanaburi, Thailand1 65.124 March31.72.1×
PattaniPattani, Thailand1 28.526 March14.02.0×
Roi EtRoi Et, Thailand1 87.225 March43.32.0×

Daily means in µg/m³. Usual: the city's median for this time of year (its days within 21 days of the date, every year, leaving out the week around it). Above usual: its highest day against that.

Against other episodes in Thailand and Laos

The largest of 7 episodes in Thailand and Laos since our records began, by cities reached.

Bars: cities reached; colour: the level of the episode's highest daily reading.

Use this page

SmogRank, Central Thailand, March 2025: 53 cities with PM2.5 at twice their usual or more, 20 to 29 March 2025, smogrank.com/episodes/2025-03-central-thailand (accessed 2 October 2026).

Download top 10 (PNG)

You're welcome to reuse a single chart, image or figure with this citation and a link. Terms.

An episode is a run of days when many cities close to each other (four or more within 350 km on a day, 8 or more in all) each had a daily PM2.5 mean of at least 25 µg/m³ and at least 2 times their usual for that time of year. Found in our own measurements, not picked by hand. How we find episodes. Values are each city's daily mean of its own monitors; causes are the usual kinds for a pattern like this, not a confirmed source.