SmogRank / Episodes / South Korea

Gyeonggi-do and Chungcheongnam-do, South Korea, July 2025

For 3 days, from 28 to 30 July 2025, 16 cities in South Korea had PM2.5 at least twice their usual for the time of year. The worst reading was Ganghwa-gun, Incheon, South Korea: 36.2 µg/m³ on 28 July, about 3.1× its usual 11.7.

No cause namedWe have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached16in 1 country
Days328 to 30 July 2025
Worst day29 July10 cities counted
Furthest above usual3.4×Gunsan

Day by day

29 July 10 cities at twice their usual or more
AsanSeonghwanCheonanAnseongHongseongSuwonSejongGongjuChinch'ŏnAnyang-siCheongju-siBuyeoSeongnam-siGwangjuJungpyongBucheon-siNonsanDaejeonPubalHanamYŏnmuGuri-siWabuGoyang-siYeojuNamyangjuYangp'yŏngOkcheonKoesanHwadoUijeongbu-siIksanKinzanNamsaYangjuChungjuMunsanWanjuJeonjuKimjeYeongdongWŏnjuGapyeongBuanJinan-gunHongch’ŏnJeongeupMungyeongChuncheonImsilSangjuChangsuCheorwonGimcheonKoch'angHwacheonNangenYecheonDamyangNeietsuJangseongGumiYangguYeonggwangYeongjuWaegwanGwangjuKuryeMasanKunwiAndongHwasunNajuHwawŏnDaeguMuanHadongSuncheonKwangyangChinjuChangnyeongBeolgyoGwangyangT’aebaekGyeongsan-siYeongamBoseongHayangGangneungSokchoMokpoJumunjinKosongCheongsong gunEisenJangheungSinanYeosuNaesŏMiryangDonghae CitySantyokuHaenamGoseongChangwonGyeongjuTongyeongYeonilKimhaePohangYangsanSinhyeonUngsangGeojeUlsanBusanGijangYesanGwangmyeongSeoulTangjinGimpo-siPyeongtaekAnsan-siIncheonGunsanOsanHwaseong-siIcheon-siSeosanGanghwa-gunTaesal-liBoryeong
25 Jul2627282930311 Aug2
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

GunsanGunsan, 25 July: 37.6 µg/m³, 3.7× usualGunsan, 26 July: 24.7 µg/m³, 2.4× usualGunsan, 27 July: 8.9 µg/m³, 0.9× usualGunsan, 28 July: 16.3 µg/m³, 1.6× usualGunsan, 29 July: 21.1 µg/m³, 2.1× usualGunsan, 30 July: 28.3 µg/m³, 2.8× usualGunsan, 31 July: 17.9 µg/m³, 1.8× usualGunsan, 1 August: 22.8 µg/m³, 2.2× usualGunsan, 2 August: 30.5 µg/m³, 3.0× usualPyeongtaekPyeongtaek, 25 July: 27.2 µg/m³, 2.6× usualPyeongtaek, 26 July: 14.3 µg/m³, 1.4× usualPyeongtaek, 27 July: 12.7 µg/m³, 1.2× usualPyeongtaek, 28 July: 25.0 µg/m³, 2.4× usualPyeongtaek, 29 July: 26.7 µg/m³, 2.5× usualPyeongtaek, 30 July: 23.4 µg/m³, 2.2× usualPyeongtaek, 31 July: 18.4 µg/m³, 1.8× usualPyeongtaek, 1 August: 31.0 µg/m³, 3.0× usualPyeongtaek, 2 August: 32.2 µg/m³, 3.1× usualGanghwa-gunGanghwa-gun, 25 July: 25.9 µg/m³, 2.2× usualGanghwa-gun, 26 July: 32.1 µg/m³, 2.7× usualGanghwa-gun, 27 July: 27.7 µg/m³, 2.4× usualGanghwa-gun, 28 July: 36.2 µg/m³, 3.1× usualGanghwa-gun, 29 July: 27.5 µg/m³, 2.4× usualGanghwa-gun, 30 July: 21.0 µg/m³, 1.8× usualGanghwa-gun, 31 July: 29.0 µg/m³, 2.5× usualGanghwa-gun, 1 August: 39.5 µg/m³, 3.4× usualGanghwa-gun, 2 August: 38.9 µg/m³, 3.3× usualHwaseong-siHwaseong-si, 25 July: 25.2 µg/m³, 2.6× usualHwaseong-si, 26 July: 21.9 µg/m³, 2.3× usualHwaseong-si, 27 July: 15.2 µg/m³, 1.6× usualHwaseong-si, 28 July: 23.0 µg/m³, 2.4× usualHwaseong-si, 29 July: 24.8 µg/m³, 2.6× usualHwaseong-si, 30 July: 29.1 µg/m³, 3.0× usualHwaseong-si, 31 July: 23.5 µg/m³, 2.4× usualHwaseong-si, 1 August: 33.5 µg/m³, 3.5× usualHwaseong-si, 2 August: 31.0 µg/m³, 3.2× usualIncheonIncheon, 25 July: 26.7 µg/m³, 2.2× usualIncheon, 26 July: 25.7 µg/m³, 2.1× usualIncheon, 27 July: 22.3 µg/m³, 1.8× usualIncheon, 28 July: 33.0 µg/m³, 2.7× usualIncheon, 29 July: 26.8 µg/m³, 2.2× usualIncheon, 30 July: 31.0 µg/m³, 2.5× usualIncheon, 31 July: 26.0 µg/m³, 2.1× usualIncheon, 1 August: 37.5 µg/m³, 3.0× usualIncheon, 2 August: 34.6 µg/m³, 2.8× usualGimpo-siGimpo-si, 25 July: 23.5 µg/m³, 1.9× usualGimpo-si, 26 July: 24.1 µg/m³, 1.9× usualGimpo-si, 27 July: 20.8 µg/m³, 1.7× usualGimpo-si, 28 July: 30.4 µg/m³, 2.5× usualGimpo-si, 29 July: 29.2 µg/m³, 2.4× usualGimpo-si, 30 July: 26.8 µg/m³, 2.2× usualGimpo-si, 31 July: 23.0 µg/m³, 1.9× usualGimpo-si, 1 August: 33.0 µg/m³, 2.7× usualGimpo-si, 2 August: 30.0 µg/m³, 2.4× usualAnsan-siAnsan-si, 25 July: 24.1 µg/m³, 2.3× usualAnsan-si, 26 July: 22.1 µg/m³, 2.1× usualAnsan-si, 27 July: 19.4 µg/m³, 1.9× usualAnsan-si, 28 July: 27.2 µg/m³, 2.6× usualAnsan-si, 29 July: 24.2 µg/m³, 2.3× usualAnsan-si, 30 July: 28.2 µg/m³, 2.7× usualAnsan-si, 31 July: 23.5 µg/m³, 2.3× usualAnsan-si, 1 August: 31.5 µg/m³, 3.0× usualAnsan-si, 2 August: 27.8 µg/m³, 2.7× usualGwangmyeongGwangmyeong, 25 July: 21.5 µg/m³, 1.8× usualGwangmyeong, 26 July: 15.8 µg/m³, 1.3× usualGwangmyeong, 27 July: 12.9 µg/m³, 1.1× usualGwangmyeong, 28 July: 26.4 µg/m³, 2.2× usualGwangmyeong, 29 July: 26.3 µg/m³, 2.2× usualGwangmyeong, 30 July: 20.8 µg/m³, 1.7× usualGwangmyeong, 31 July: 19.2 µg/m³, 1.6× usualGwangmyeong, 1 August: 23.7 µg/m³, 2.0× usualGwangmyeong, 2 August: 26.6 µg/m³, 2.2× usualSeoulSeoul, 25 July: 22.6 µg/m³, 2.1× usualSeoul, 26 July: 14.7 µg/m³, 1.3× usualSeoul, 27 July: 11.8 µg/m³, 1.1× usualSeoul, 28 July: 26.1 µg/m³, 2.4× usualSeoul, 29 July: 26.7 µg/m³, 2.4× usualSeoul, 30 July: 19.2 µg/m³, 1.8× usualSeoul, 31 July: 18.4 µg/m³, 1.7× usualSeoul, 1 August: 24.6 µg/m³, 2.3× usualSeoul, 2 August: 23.4 µg/m³, 2.1× usualIcheon-siIcheon-si, 25 July: 22.4 µg/m³, 2.2× usualIcheon-si, 26 July: 13.5 µg/m³, 1.3× usualIcheon-si, 27 July: 9.6 µg/m³, 0.9× usualIcheon-si, 28 July: 21.6 µg/m³, 2.1× usualIcheon-si, 29 July: 30.4 µg/m³, 3.0× usualIcheon-si, 30 July: 19.0 µg/m³, 1.8× usualIcheon-si, 31 July: 16.8 µg/m³, 1.6× usualIcheon-si, 1 August: 23.8 µg/m³, 2.3× usualIcheon-si, 2 August: 31.8 µg/m³, 3.1× usualTangjinTangjin, 25 July: no readingTangjin, 26 July: no readingTangjin, 27 July: 20.6 µg/m³, 1.6× usualTangjin, 28 July: 24.3 µg/m³, 1.9× usualTangjin, 29 July: 28.7 µg/m³, 2.3× usualTangjin, 30 July: 31.4 µg/m³, 2.5× usualTangjin, 31 July: 24.1 µg/m³, 1.9× usualTangjin, 1 August: 30.1 µg/m³, 2.4× usualTangjin, 2 August: 29.8 µg/m³, 2.3× usualYesanYesan, 25 July: no readingYesan, 26 July: no readingYesan, 27 July: 14.8 µg/m³, 1.2× usualYesan, 28 July: 21.4 µg/m³, 1.7× usualYesan, 29 July: 26.7 µg/m³, 2.1× usualYesan, 30 July: 25.1 µg/m³, 2.0× usualYesan, 31 July: 20.5 µg/m³, 1.6× usualYesan, 1 August: 28.5 µg/m³, 2.3× usualYesan, 2 August: 32.4 µg/m³, 2.6× usualOsanOsan, 25 July: 22.9 µg/m³, 2.4× usualOsan, 26 July: 11.7 µg/m³, 1.2× usualOsan, 27 July: 8.6 µg/m³, 0.9× usualOsan, 28 July: 22.4 µg/m³, 2.3× usualOsan, 29 July: 26.6 µg/m³, 2.8× usualOsan, 30 July: 17.1 µg/m³, 1.8× usualOsan, 31 July: 17.5 µg/m³, 1.8× usualOsan, 1 August: 24.8 µg/m³, 2.6× usualOsan, 2 August: 31.1 µg/m³, 3.2× usualBoryeongBoryeong, 25 July: no readingBoryeong, 26 July: no readingBoryeong, 27 July: 10.6 µg/m³, 1.2× usualBoryeong, 28 July: 14.1 µg/m³, 1.5× usualBoryeong, 29 July: 21.8 µg/m³, 2.4× usualBoryeong, 30 July: 30.9 µg/m³, 3.4× usualBoryeong, 31 July: 18.7 µg/m³, 2.1× usualBoryeong, 1 August: 25.1 µg/m³, 2.8× usualBoryeong, 2 August: 23.8 µg/m³, 2.6× usualTaesal-liTaesal-li, 25 July: no readingTaesal-li, 26 July: no readingTaesal-li, 27 July: 9.6 µg/m³, 1.1× usualTaesal-li, 28 July: 17.3 µg/m³, 2.1× usualTaesal-li, 29 July: 22.7 µg/m³, 2.7× usualTaesal-li, 30 July: 27.3 µg/m³, 3.3× usualTaesal-li, 31 July: 22.5 µg/m³, 2.7× usualTaesal-li, 1 August: 28.0 µg/m³, 3.3× usualTaesal-li, 2 August: 25.0 µg/m³, 3.0× usualSeosanSeosan, 25 July: no readingSeosan, 26 July: no readingSeosan, 27 July: 9.7 µg/m³, 1.1× usualSeosan, 28 July: 14.5 µg/m³, 1.7× usualSeosan, 29 July: 20.5 µg/m³, 2.4× usualSeosan, 30 July: 26.7 µg/m³, 3.1× usualSeosan, 31 July: 19.8 µg/m³, 2.3× usualSeosan, 1 August: 26.6 µg/m³, 3.1× usualSeosan, 2 August: 24.9 µg/m³, 2.9× usual25 Jul2627282930311 Aug2
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
GunsanJeollabuk-do, South Korea1 37.625 July10.23.7×
Hwaseong-siGyeonggi-do, South Korea1 33.51 August9.63.5×
BoryeongChungcheongnam-do, South Korea1 30.930 July9.13.4×
Ganghwa-gunIncheon, South Korea2 39.51 August11.73.4×
Taesal-liChungcheongnam-do, South Korea1 28.01 August8.43.3×
OsanGyeonggi-do, South Korea1 31.12 August9.63.2×
SeosanChungcheongnam-do, South Korea1 26.730 July8.53.1×
Icheon-siGyeonggi-do, South Korea1 31.82 August10.33.1×
PyeongtaekGyeonggi-do, South Korea2 32.22 August10.53.1×
Ansan-siGyeonggi-do, South Korea2 31.51 August10.43.0×
IncheonIncheon, South Korea3 37.51 August12.43.0×
Gimpo-siGyeonggi-do, South Korea3 33.01 August12.42.7×
YesanChungcheongnam-do, South Korea1 32.42 August12.62.6×
TangjinChungcheongnam-do, South Korea2 31.430 July12.72.5×
SeoulSeoul, South Korea2 26.729 July10.92.4×
GwangmyeongGyeonggi-do, South Korea2 26.62 August11.92.2×

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 South Korea

Number 37 of 43 episodes in South Korea since our records began, by cities reached.

Bars: cities reached; colour: the level of the episode's highest daily reading. All 43.

Use this page

SmogRank, Gyeonggi-do and Chungcheongnam-do, South Korea, July 2025: 16 cities with PM2.5 at twice their usual or more, 28 to 30 July 2025, smogrank.com/episodes/2025-07-gyeonggi-do-and-chungcheongnam-do-south-korea (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.