SmogRank / Episodes / Thailand

North-eastern Thailand, February 2024

For 1 day, on 9 February 2024, 9 cities in Thailand had PM2.5 at least twice their usual for the time of year. The worst reading was Sukhothai, Sukhothai, Thailand: 77.6 µg/m³ on 9 February, about 2.3× its usual 33.1.

No cause namedWe have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached9in 1 country
Days19 February 2024
Worst day9 February9 cities counted
Furthest above usual2.7×Chaiyaphum

Day by day

9 February 9 cities at twice their usual or more
Khon KaenNakhon RatchasimaUdon ThaniBuri RamLoeiSurinPhichitSakon NakhonSaraburiLop BuriNakhon NayokSing BuriAmnat CharoenSi Maha PhotChai NatMukdahanPhra Nakhon Si AyutthayaPakxanUttaraditKhlong LuangNong ChokSuphan BuriKhlong Sam WaSai MaiKamphaeng PhetKhan Na YaoLak SiLat KrabangBueng KumSaphan SungBang KapiMueang NonthaburiBan Khlong PrawetPhraeBangkokNong KhaemNakhon PathomKanchanaburiLampangMae SotLamphunNakhon SawanPhetchabunUbon RatchathaniKalasinSi Sa KetYasothonSukhothaiNong Bua LamphuChaiyaphum
6 Feb789101112
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, 6 February: 54.1 µg/m³, 2.0× usualChaiyaphum, 7 February: 77.5 µg/m³, 2.9× usualChaiyaphum, 8 February: no readingChaiyaphum, 9 February: 74.0 µg/m³, 2.7× usualChaiyaphum, 10 February: 44.5 µg/m³, 1.6× usualChaiyaphum, 11 February: no readingChaiyaphum, 12 February: no readingUbon RatchathaniUbon Ratchathani, 6 February: 63.6 µg/m³, 2.1× usualUbon Ratchathani, 7 February: 72.4 µg/m³, 2.4× usualUbon Ratchathani, 8 February: no readingUbon Ratchathani, 9 February: 62.8 µg/m³, 2.0× usualUbon Ratchathani, 10 February: 25.3 µg/m³, 0.8× usualUbon Ratchathani, 11 February: no readingUbon Ratchathani, 12 February: no readingKalasinKalasin, 6 February: 62.6 µg/m³, 2.0× usualKalasin, 7 February: 66.8 µg/m³, 2.1× usualKalasin, 8 February: no readingKalasin, 9 February: 66.1 µg/m³, 2.1× usualKalasin, 10 February: 29.9 µg/m³, 0.9× usualKalasin, 11 February: no readingKalasin, 12 February: no readingNong Bua LamphuNong Bua Lamphu, 6 February: 43.1 µg/m³, 1.6× usualNong Bua Lamphu, 7 February: 60.6 µg/m³, 2.2× usualNong Bua Lamphu, 8 February: no readingNong Bua Lamphu, 9 February: 71.2 µg/m³, 2.6× usualNong Bua Lamphu, 10 February: 35.1 µg/m³, 1.3× usualNong Bua Lamphu, 11 February: no readingNong Bua Lamphu, 12 February: no readingYasothonYasothon, 6 February: 54.6 µg/m³, 1.9× usualYasothon, 7 February: 59.6 µg/m³, 2.1× usualYasothon, 8 February: no readingYasothon, 9 February: 59.3 µg/m³, 2.1× usualYasothon, 10 February: 21.8 µg/m³, 0.8× usualYasothon, 11 February: no readingYasothon, 12 February: no readingSukhothaiSukhothai, 6 February: 56.0 µg/m³, 1.7× usualSukhothai, 7 February: 55.3 µg/m³, 1.7× usualSukhothai, 8 February: no readingSukhothai, 9 February: 77.6 µg/m³, 2.3× usualSukhothai, 10 February: 69.8 µg/m³, 2.1× usualSukhothai, 11 February: no readingSukhothai, 12 February: no readingPhetchabunPhetchabun, 6 February: 38.7 µg/m³, 1.2× usualPhetchabun, 7 February: 54.3 µg/m³, 1.6× usualPhetchabun, 8 February: no readingPhetchabun, 9 February: 68.6 µg/m³, 2.0× usualPhetchabun, 10 February: 53.9 µg/m³, 1.6× usualPhetchabun, 11 February: no readingPhetchabun, 12 February: no readingNakhon SawanNakhon Sawan, 6 February: 59.5 µg/m³, 1.8× usualNakhon Sawan, 7 February: 60.2 µg/m³, 1.8× usualNakhon Sawan, 8 February: no readingNakhon Sawan, 9 February: 68.4 µg/m³, 2.0× usualNakhon Sawan, 10 February: 35.5 µg/m³, 1.1× usualNakhon Sawan, 11 February: no readingNakhon Sawan, 12 February: no readingSi Sa KetSi Sa Ket, 6 February: 42.7 µg/m³, 1.8× usualSi Sa Ket, 7 February: 43.2 µg/m³, 1.8× usualSi Sa Ket, 8 February: no readingSi Sa Ket, 9 February: 50.5 µg/m³, 2.1× usualSi Sa Ket, 10 February: no readingSi Sa Ket, 11 February: no readingSi Sa Ket, 12 February: no reading6 Feb789101112
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 February27.12.9×
Nong Bua LamphuNong Bua Lamphu, Thailand1 71.29 February27.12.6×
Ubon RatchathaniUbon Ratchathani, Thailand1 72.47 February30.82.4×
SukhothaiSukhothai, Thailand1 77.69 February33.12.3×
Si Sa KetSi Sa Ket, Thailand1 50.59 February23.72.1×
KalasinKalasin, Thailand1 66.87 February31.92.1×
YasothonYasothon, Thailand1 59.67 February28.82.1×
Nakhon SawanNakhon Sawan, Thailand1 68.49 February33.52.0×
PhetchabunPhetchabun, Thailand1 68.69 February33.62.0×

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

Number 17 of 24 episodes in Thailand since our records began, by cities reached.

Bars: cities reached; colour: the level of the episode's highest daily reading. All 24.

Use this page

SmogRank, North-eastern Thailand, February 2024: 9 cities with PM2.5 at twice their usual or more, 9 February 2024, smogrank.com/episodes/2024-02-north-eastern-thailand-2 (accessed 3 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.