SmogRank / Episodes / South Korea
South Korea, 28 to 30 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 named We have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached 16 in 1 country
Days 3 28 to 30 July 2025
Worst day 29 July 10 cities counted
Furthest above usual 3.4× Boryeong
Day by day
Play 29 July 10 cities at twice their usual or more
Asan Seonghwan Cheonan Anseong Hongseong Suwon Sejong Gongju Chinch'ŏn Anyang-si Cheongju-si Buyeo Seongnam-si Gwangju Jungpyong Bucheon-si Nonsan Daejeon Pubal Hanam Yŏnmu Guri-si Wabu Goyang-si Yeoju Namyangju Yangp'yŏng Okcheon Koesan Hwado Uijeongbu-si Iksan Kinzan Namsa Yangju Chungju Munsan Wanju Jeonju Kimje Yeongdong Wŏnju Gapyeong Buan Jinan-gun Hongch’ŏn Jeongeup Mungyeong Chuncheon Imsil Sangju Changsu Cheorwon Gimcheon Koch'ang Hwacheon Nangen Yecheon Damyang Neietsu Jangseong Gumi Yanggu Yeonggwang Yeongju Waegwan Gwangju Kurye Masan Kunwi Andong Hwasun Naju Hwawŏn Daegu Muan Hadong Suncheon Kwangyang Chinju Changnyeong Beolgyo Gwangyang T’aebaek Gyeongsan-si Yeongam Boseong Hayang Gangneung Sokcho Mokpo Jumunjin Kosong Cheongsong gun Eisen Jangheung Sinan Yeosu Naesŏ Miryang Donghae City Santyoku Haenam Goseong Changwon Gyeongju Tongyeong Yeonil Kimhae Pohang Yangsan Sinhyeon Ungsang Geoje Ulsan Busan Gijang Yesan Gwangmyeong Seoul Pyeongtaek Gimpo-si Tangjin Ansan-si Incheon Osan Gunsan Hwaseong-si Icheon-si Seosan Ganghwa-gun Taesal-li Boryeong 25 Jul 26 27 28 29 30 31 1 Aug 2 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
Ganghwa-gun Ganghwa-gun, 25 July: 25.9 µg/m³ Ganghwa-gun, 26 July: 32.1 µg/m³ Ganghwa-gun, 27 July: 27.7 µg/m³ Ganghwa-gun, 28 July: 36.2 µg/m³, 3.1× its usual 11.7 Ganghwa-gun, 29 July: 27.5 µg/m³, 2.5× its usual 11.2 Ganghwa-gun, 30 July: 21.0 µg/m³ Ganghwa-gun, 31 July: 29.0 µg/m³ Ganghwa-gun, 1 August: 39.5 µg/m³ Ganghwa-gun, 2 August: 38.9 µg/m³ Incheon Incheon, 25 July: 26.7 µg/m³ Incheon, 26 July: 25.7 µg/m³ Incheon, 27 July: 22.3 µg/m³ Incheon, 28 July: 33.0 µg/m³, 2.7× its usual 12.4 Incheon, 29 July: 26.8 µg/m³, 2.2× its usual 12.4 Incheon, 30 July: 31.0 µg/m³, 2.5× its usual 12.4 Incheon, 31 July: 26.0 µg/m³ Incheon, 1 August: 37.5 µg/m³ Incheon, 2 August: 34.6 µg/m³ Gimpo-si Gimpo-si, 25 July: 23.5 µg/m³ Gimpo-si, 26 July: 24.1 µg/m³ Gimpo-si, 27 July: 20.8 µg/m³ Gimpo-si, 28 July: 30.4 µg/m³, 2.5× its usual 12.4 Gimpo-si, 29 July: 29.2 µg/m³, 2.4× its usual 12.4 Gimpo-si, 30 July: 26.8 µg/m³, 2.2× its usual 12.4 Gimpo-si, 31 July: 23.0 µg/m³ Gimpo-si, 1 August: 33.0 µg/m³ Gimpo-si, 2 August: 30.0 µg/m³ Ansan-si Ansan-si, 25 July: 24.1 µg/m³ Ansan-si, 26 July: 22.1 µg/m³ Ansan-si, 27 July: 19.4 µg/m³ Ansan-si, 28 July: 27.2 µg/m³, 2.6× its usual 10.5 Ansan-si, 29 July: 24.2 µg/m³ Ansan-si, 30 July: 28.2 µg/m³, 2.7× its usual 10.4 Ansan-si, 31 July: 23.5 µg/m³ Ansan-si, 1 August: 31.5 µg/m³ Ansan-si, 2 August: 27.8 µg/m³ Gwangmyeong Gwangmyeong, 25 July: 21.5 µg/m³ Gwangmyeong, 26 July: 15.8 µg/m³ Gwangmyeong, 27 July: 12.9 µg/m³ Gwangmyeong, 28 July: 26.4 µg/m³, 2.2× its usual 11.9 Gwangmyeong, 29 July: 26.3 µg/m³, 2.3× its usual 11.6 Gwangmyeong, 30 July: 20.8 µg/m³ Gwangmyeong, 31 July: 19.2 µg/m³ Gwangmyeong, 1 August: 23.7 µg/m³ Gwangmyeong, 2 August: 26.6 µg/m³ Seoul Seoul, 25 July: 22.6 µg/m³ Seoul, 26 July: 14.7 µg/m³ Seoul, 27 July: 11.8 µg/m³ Seoul, 28 July: 26.1 µg/m³, 2.3× its usual 11.3 Seoul, 29 July: 26.7 µg/m³, 2.4× its usual 10.9 Seoul, 30 July: 19.2 µg/m³ Seoul, 31 July: 18.4 µg/m³ Seoul, 1 August: 24.6 µg/m³ Seoul, 2 August: 23.4 µg/m³ Pyeongtaek Pyeongtaek, 25 July: 27.2 µg/m³ Pyeongtaek, 26 July: 14.3 µg/m³ Pyeongtaek, 27 July: 12.7 µg/m³ Pyeongtaek, 28 July: 25.0 µg/m³, 2.4× its usual 10.6 Pyeongtaek, 29 July: 26.7 µg/m³, 2.5× its usual 10.5 Pyeongtaek, 30 July: 23.4 µg/m³ Pyeongtaek, 31 July: 18.4 µg/m³ Pyeongtaek, 1 August: 31.0 µg/m³ Pyeongtaek, 2 August: 32.2 µg/m³ Icheon-si Icheon-si, 25 July: 22.4 µg/m³ Icheon-si, 26 July: 13.5 µg/m³ Icheon-si, 27 July: 9.6 µg/m³ Icheon-si, 28 July: 21.6 µg/m³ Icheon-si, 29 July: 30.4 µg/m³, 3.0× its usual 10.3 Icheon-si, 30 July: 19.0 µg/m³ Icheon-si, 31 July: 16.8 µg/m³ Icheon-si, 1 August: 23.8 µg/m³ Icheon-si, 2 August: 31.8 µg/m³ Tangjin Tangjin, 25 July: no reading Tangjin, 26 July: no reading Tangjin, 27 July: 20.6 µg/m³ Tangjin, 28 July: 24.3 µg/m³ Tangjin, 29 July: 28.7 µg/m³, 2.3× its usual 12.4 Tangjin, 30 July: 31.4 µg/m³, 2.5× its usual 12.7 Tangjin, 31 July: 24.1 µg/m³ Tangjin, 1 August: 30.1 µg/m³ Tangjin, 2 August: 29.8 µg/m³ Yesan Yesan, 25 July: no reading Yesan, 26 July: no reading Yesan, 27 July: 14.8 µg/m³ Yesan, 28 July: 21.4 µg/m³ Yesan, 29 July: 26.7 µg/m³, 2.1× its usual 12.6 Yesan, 30 July: 25.1 µg/m³ Yesan, 31 July: 20.5 µg/m³ Yesan, 1 August: 28.5 µg/m³ Yesan, 2 August: 32.4 µg/m³ Osan Osan, 25 July: 22.9 µg/m³ Osan, 26 July: 11.7 µg/m³ Osan, 27 July: 8.6 µg/m³ Osan, 28 July: 22.4 µg/m³ Osan, 29 July: 26.6 µg/m³, 2.8× its usual 9.6 Osan, 30 July: 17.1 µg/m³ Osan, 31 July: 17.5 µg/m³ Osan, 1 August: 24.8 µg/m³ Osan, 2 August: 31.1 µg/m³ Boryeong Boryeong, 25 July: no reading Boryeong, 26 July: no reading Boryeong, 27 July: 10.6 µg/m³ Boryeong, 28 July: 14.1 µg/m³ Boryeong, 29 July: 21.8 µg/m³ Boryeong, 30 July: 30.9 µg/m³, 3.4× its usual 9.1 Boryeong, 31 July: 18.7 µg/m³ Boryeong, 1 August: 25.1 µg/m³ Boryeong, 2 August: 23.8 µg/m³ Hwaseong-si Hwaseong-si, 25 July: 25.2 µg/m³ Hwaseong-si, 26 July: 21.9 µg/m³ Hwaseong-si, 27 July: 15.2 µg/m³ Hwaseong-si, 28 July: 23.0 µg/m³ Hwaseong-si, 29 July: 24.8 µg/m³ Hwaseong-si, 30 July: 29.1 µg/m³, 3.0× its usual 9.6 Hwaseong-si, 31 July: 23.5 µg/m³ Hwaseong-si, 1 August: 33.5 µg/m³ Hwaseong-si, 2 August: 31.0 µg/m³ Gunsan Gunsan, 25 July: 37.6 µg/m³ Gunsan, 26 July: 24.7 µg/m³ Gunsan, 27 July: 8.9 µg/m³ Gunsan, 28 July: 16.3 µg/m³ Gunsan, 29 July: 21.1 µg/m³ Gunsan, 30 July: 28.3 µg/m³, 2.8× its usual 10.2 Gunsan, 31 July: 17.9 µg/m³ Gunsan, 1 August: 22.8 µg/m³ Gunsan, 2 August: 30.5 µg/m³ Taesal-li Taesal-li, 25 July: no reading Taesal-li, 26 July: no reading Taesal-li, 27 July: 9.6 µg/m³ Taesal-li, 28 July: 17.3 µg/m³ Taesal-li, 29 July: 22.7 µg/m³ Taesal-li, 30 July: 27.3 µg/m³, 3.3× its usual 8.4 Taesal-li, 31 July: 22.5 µg/m³ Taesal-li, 1 August: 28.0 µg/m³ Taesal-li, 2 August: 25.0 µg/m³ Seosan Seosan, 25 July: no reading Seosan, 26 July: no reading Seosan, 27 July: 9.7 µg/m³ Seosan, 28 July: 14.5 µg/m³ Seosan, 29 July: 20.5 µg/m³ Seosan, 30 July: 26.7 µg/m³, 3.1× its usual 8.5 Seosan, 31 July: 19.8 µg/m³ Seosan, 1 August: 26.6 µg/m³ Seosan, 2 August: 24.9 µg/m³ 25 Jul 26 27 28 29 30 31 1 Aug 2 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. Good 0–50
Moderate 51–100
Sensitive groups 101–150
Unhealthy 151–200
Very unhealthy 201–300
Hazardous 301+
Every city it reached
City Days Highest Usual Above usual
Boryeong Chungcheongnam-do, South Korea 1 30 July 9.1 3.4× Taesal-li Chungcheongnam-do, South Korea 1 30 July 8.4 3.3× Ganghwa-gun Incheon, South Korea 2 28 July 11.7 3.1× Seosan Chungcheongnam-do, South Korea 1 30 July 8.5 3.1× Icheon-si Gyeonggi-do, South Korea 1 29 July 10.3 3.0× Hwaseong-si Gyeonggi-do, South Korea 1 30 July 9.6 3.0× Gunsan Jeollabuk-do, South Korea 1 30 July 10.2 2.8× Osan Gyeonggi-do, South Korea 1 29 July 9.6 2.8× Incheon Incheon, South Korea 3 28 July 12.4 2.7× Ansan-si Gyeonggi-do, South Korea 2 30 July 10.4 2.7× Tangjin Chungcheongnam-do, South Korea 2 30 July 12.7 2.5× Gimpo-si Gyeonggi-do, South Korea 3 28 July 12.4 2.5× Pyeongtaek Gyeonggi-do, South Korea 2 29 July 10.5 2.5× Seoul Seoul, South Korea 2 29 July 10.9 2.4× Gwangmyeong Gyeonggi-do, South Korea 2 28 July 11.9 2.2× Yesan Chungcheongnam-do, South Korea 1 29 July 12.6 2.1×
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 South Korea
Number 51 of 63 episodes in South Korea since our records began, by cities reached.
Japan and South Korea, March 2025 454 Japan and South Korea, March 2026 305 Japan and South Korea, January 2025 274 Japan and South Korea, February and March 2025 192 South Korea and Japan, January 2026 169 South Korea and Japan, 10 to 15 February 2026 147 South Korea, 14 to 16 February 2025 132 South Korea and Japan, November 2025 128 South Korea, February 2026 121 South Korea, 7 December 2025 113 South Korea, 13 to 14 January 2025 113 South Korea, 16 to 20 December 2025 107 South Korea, 28 to 30 July 2025 16 Bars: cities reached; colour: the level of the episode's highest daily reading. All 63 .
Use this page SmogRank, South Korea, 28 to 30 July 2025: 16 cities with PM2.5 at twice their usual or more, 28 to 30 July 2025, smogrank.com/episodes/2025-07-28-south-korea (accessed 4 October 2026).
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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.
