SmogRank / Episodes / Thailand

Northern Thailand, 7 February 2024

For 1 day, on 7 February 2024, 9 cities in Thailand had PM2.5 at least twice their usual for the time of year. The worst reading was Chaiyaphum, Chaiyaphum, Thailand: 77.5 µg/m³ on 7 February, about 2.9× its usual 27.0.

No cause namedWe have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached9in 1 country
Days17 February 2024
Worst day7 February9 cities counted
Furthest above usual2.9×Chaiyaphum

Day by day

7 February 9 cities at twice their usual or more
Nakhon RatchasimaKhon KaenBuri RamPhetchabunSurinSaraburiNakhon NayokLop BuriSi Maha PhotUdon ThaniSing BuriAranyaprathetLoeiPhichitPhra Nakhon Si AyutthayaNakhon SawanChai NatSi Sa KetKhlong LuangNong ChokKhlong Sam WaSai MaiKhan Na YaoLat KrabangLak SiSuphan BuriBueng KumSaphan SungBang KapiBan Khlong PrawetMueang NonthaburiBang Bo DistrictBang NaBangkokPhra PradaengSamut PrakanBang Khun ThianNong KhaemBan Samae DamSukhothaiNakhon PathomSamut SakhonKamphaeng PhetUttaraditRatchaburiMae SotAmnat CharoenYasothonKalasinKanchanaburiNong Bua LamphuUbon RatchathaniMukdahanSakon NakhonChaiyaphum
4 Feb5678910
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

ChaiyaphumChaiyaphum, 4 February: 43.9 µg/m³Chaiyaphum, 5 February: 44.8 µg/m³Chaiyaphum, 6 February: 54.1 µg/m³Chaiyaphum, 7 February: 77.5 µg/m³, 2.9× its usual 27.0Chaiyaphum, 8 February: no readingChaiyaphum, 9 February: 74.0 µg/m³Chaiyaphum, 10 February: 44.5 µg/m³KanchanaburiKanchanaburi, 4 February: no readingKanchanaburi, 5 February: 48.5 µg/m³Kanchanaburi, 6 February: 70.5 µg/m³Kanchanaburi, 7 February: 74.9 µg/m³, 2.2× its usual 34.8Kanchanaburi, 8 February: no readingKanchanaburi, 9 February: 49.3 µg/m³Kanchanaburi, 10 February: 41.7 µg/m³MukdahanMukdahan, 4 February: 69.1 µg/m³Mukdahan, 5 February: 67.6 µg/m³Mukdahan, 6 February: 66.6 µg/m³Mukdahan, 7 February: 73.1 µg/m³, 2.7× its usual 27.5Mukdahan, 8 February: no readingMukdahan, 9 February: 45.0 µg/m³Mukdahan, 10 February: 24.2 µg/m³Ubon RatchathaniUbon Ratchathani, 4 February: 81.1 µg/m³Ubon Ratchathani, 5 February: 72.3 µg/m³Ubon Ratchathani, 6 February: 63.6 µg/m³Ubon Ratchathani, 7 February: 72.4 µg/m³, 2.4× its usual 30.8Ubon Ratchathani, 8 February: no readingUbon Ratchathani, 9 February: 62.8 µg/m³Ubon Ratchathani, 10 February: 25.3 µg/m³KalasinKalasin, 4 February: 56.5 µg/m³Kalasin, 5 February: 63.2 µg/m³Kalasin, 6 February: 62.6 µg/m³Kalasin, 7 February: 66.8 µg/m³, 2.1× its usual 31.9Kalasin, 8 February: no readingKalasin, 9 February: 66.1 µg/m³Kalasin, 10 February: 29.9 µg/m³Nong Bua LamphuNong Bua Lamphu, 4 February: 40.6 µg/m³Nong Bua Lamphu, 5 February: 30.0 µg/m³Nong Bua Lamphu, 6 February: 43.1 µg/m³Nong Bua Lamphu, 7 February: 60.6 µg/m³, 2.3× its usual 26.9Nong Bua Lamphu, 8 February: no readingNong Bua Lamphu, 9 February: 71.2 µg/m³Nong Bua Lamphu, 10 February: 35.1 µg/m³YasothonYasothon, 4 February: 55.2 µg/m³Yasothon, 5 February: 55.8 µg/m³Yasothon, 6 February: 54.6 µg/m³Yasothon, 7 February: 59.6 µg/m³, 2.1× its usual 28.8Yasothon, 8 February: no readingYasothon, 9 February: 59.3 µg/m³Yasothon, 10 February: 21.8 µg/m³Amnat CharoenAmnat Charoen, 4 February: 53.0 µg/m³Amnat Charoen, 5 February: 57.0 µg/m³Amnat Charoen, 6 February: 50.3 µg/m³Amnat Charoen, 7 February: 54.9 µg/m³, 2.1× its usual 25.8Amnat Charoen, 8 February: no readingAmnat Charoen, 9 February: 43.1 µg/m³Amnat Charoen, 10 February: 13.8 µg/m³Sakon NakhonSakon Nakhon, 4 February: 40.5 µg/m³Sakon Nakhon, 5 February: 37.6 µg/m³Sakon Nakhon, 6 February: 40.8 µg/m³Sakon Nakhon, 7 February: 50.0 µg/m³, 2.8× its usual 17.6Sakon Nakhon, 8 February: no readingSakon Nakhon, 9 February: 21.3 µg/m³Sakon Nakhon, 10 February: 9.8 µg/m³4 Feb5678910
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
ChaiyaphumChaiyaphum, Thailand1 77.57 February27.02.9×
Sakon NakhonSakon Nakhon, Thailand1 50.07 February17.62.8×
MukdahanMukdahan, Thailand1 73.17 February27.52.7×
Ubon RatchathaniUbon Ratchathani, Thailand1 72.47 February30.82.4×
Nong Bua LamphuNong Bua Lamphu, Thailand1 60.67 February26.92.3×
KanchanaburiKanchanaburi, Thailand1 74.97 February34.82.2×
KalasinKalasin, Thailand1 66.87 February31.92.1×
YasothonYasothon, Thailand1 59.67 February28.82.1×
Amnat CharoenAmnat Charoen, Thailand1 54.97 February25.82.1×

Daily means in µg/m³, over the days each city counted in this episode. Highest: its highest of those days. Usual: the city's median for the time of year of that day (its days within 21 days of the date, every year, leaving out the week around it). Above usual: its highest day against that, with a usual under 5 µg/m³ taken as 5.

Against other episodes in Thailand

Number 18 of 23 episodes in Thailand since our records began, by cities reached.

Bars: cities reached; colour: the level of the episode's highest daily reading. All 23.

Use this page

SmogRank, Northern Thailand, 7 February 2024: 9 cities with PM2.5 at twice their usual or more, 7 February 2024, smogrank.com/episodes/2024-02-07-northern-thailand (accessed 4 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.