SmogRank / Episodes / South Korea
South Korea, April 2026
For 2 days, from 11 to 12 April 2026, 12 cities in South Korea had PM2.5 at least twice their usual for the time of year. The worst reading was Yŏnmu, Chungcheongnam-do, South Korea: 44.9 µg/m³ on 11 April, about 2.2× its usual 20.5.
No cause named We have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached 12 in 1 country
Days 2 11 to 12 April 2026
Worst day 11 April 8 cities counted
Furthest above usual 2.4× Haenam
Day by day
Play 11 April 8 cities at twice their usual or more
Jangheung Mokpo Boseong Hwasun Jangseong Damyang Beolgyo Sinan Suncheon Jeongeup Kurye Kwangyang Nangen Yeosu Buan Gwangyang Imsil Kimje Hadong Changsu Iksan Namsa Gunsan Jinan-gun Jeju City Chinju Nonsan Buyeo Kinzan Seogwipo Boryeong Goseong Daejeon Tongyeong Gongju Okcheon Yeongdong Hongseong Naesŏ Sejong Yesan Sinhyeon Changnyeong Gimcheon Geoje Cheongju-si Changwon Seosan Asan Hwawŏn Waegwan Cheonan Gumi Tangjin Miryang Daegu Seonghwan Sangju Jungpyong Chinch'ŏn Kimhae Taesal-li Pyeongtaek Gyeongsan-si Koesan Anseong Busan Mungyeong Kunwi Yangsan Hayang Osan Hwaseong-si Chungju Eisen Ungsang Gijang Yecheon Tsushima Andong Ulsan Gyeongju Yeongju Cheongsong gun Yeonil Pohang Neietsu Gotō Iki T’aebaek Matsuura Sasebo Saikai Imarichō-kō Karatsu Takeo Itoshima Ureshinomachi-shimojuku Maebaru-chūō Togitsu Taku Obita Ōmura Nagasaki Kashima Higashigō Isahaya Fukuoka Koga Saga Kanzakimachi-kanzaki Kasuga Munakata Wakasugi Yanagawa Tosu Koga Ogōri Chikugo Nakama Ōmuta Iizuka Nōgata Arao Hondomachi-hondo Tanushimarumachi-toyoki Yame Kitakyushu Tagawa Tamana Ukiha Shimonoseki Ōyanomachi-noboritate Kanda Yukuhashi Uekimachi-mōno Kumamoto Hita Uto Kikuchi Kotō Honmachi Buzen Ōzu Mifune Aso Gaigeturi Muan Wanju Gwangju Masan Jeonju Yŏnmu Naju Yeongam Koch'ang Yeonggwang Haenam 8 Apr 9 10 11 12 13 14 15 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
Yŏnmu Yŏnmu, 8 April: 15.0 µg/m³, 0.7× usual Yŏnmu, 9 April: 14.5 µg/m³, 0.7× usual Yŏnmu, 10 April: 16.4 µg/m³, 0.8× usual Yŏnmu, 11 April: 44.9 µg/m³, 2.2× usual Yŏnmu, 12 April: 38.6 µg/m³, 1.9× usual Yŏnmu, 13 April: 22.6 µg/m³, 1.1× usual Yŏnmu, 14 April: 30.0 µg/m³, 1.5× usual Yŏnmu, 15 April: 31.1 µg/m³, 1.5× usual Haenam Haenam, 8 April: 9.5 µg/m³, 0.5× usual Haenam, 9 April: 9.0 µg/m³, 0.5× usual Haenam, 10 April: 19.7 µg/m³, 1.1× usual Haenam, 11 April: 42.0 µg/m³, 2.4× usual Haenam, 12 April: 29.2 µg/m³, 1.7× usual Haenam, 13 April: 16.1 µg/m³, 0.9× usual Haenam, 14 April: 20.8 µg/m³, 1.2× usual Haenam, 15 April: 26.7 µg/m³, 1.5× usual Wanju Wanju, 8 April: 12.4 µg/m³, 0.6× usual Wanju, 9 April: 8.9 µg/m³, 0.4× usual Wanju, 10 April: 17.7 µg/m³, 0.9× usual Wanju, 11 April: 40.5 µg/m³, 2.0× usual Wanju, 12 April: 40.4 µg/m³, 2.0× usual Wanju, 13 April: 24.4 µg/m³, 1.2× usual Wanju, 14 April: 30.7 µg/m³, 1.5× usual Wanju, 15 April: 33.4 µg/m³, 1.7× usual Koch'ang Koch'ang, 8 April: 10.0 µg/m³, 0.6× usual Koch'ang, 9 April: 7.4 µg/m³, 0.5× usual Koch'ang, 10 April: 15.5 µg/m³, 1.0× usual Koch'ang, 11 April: 36.5 µg/m³, 2.3× usual Koch'ang, 12 April: 30.0 µg/m³, 1.9× usual Koch'ang, 13 April: 17.4 µg/m³, 1.1× usual Koch'ang, 14 April: 20.4 µg/m³, 1.3× usual Koch'ang, 15 April: 19.0 µg/m³, 1.2× usual Jeonju Jeonju, 8 April: 11.1 µg/m³, 0.7× usual Jeonju, 9 April: 6.4 µg/m³, 0.4× usual Jeonju, 10 April: 15.5 µg/m³, 0.9× usual Jeonju, 11 April: 34.7 µg/m³, 2.0× usual Jeonju, 12 April: 35.5 µg/m³, 2.1× usual Jeonju, 13 April: 18.3 µg/m³, 1.1× usual Jeonju, 14 April: 22.6 µg/m³, 1.3× usual Jeonju, 15 April: 24.6 µg/m³, 1.4× usual Yeongam Yeongam, 8 April: 7.5 µg/m³, 0.5× usual Yeongam, 9 April: 7.4 µg/m³, 0.5× usual Yeongam, 10 April: 17.8 µg/m³, 1.2× usual Yeongam, 11 April: 34.1 µg/m³, 2.3× usual Yeongam, 12 April: 33.3 µg/m³, 2.2× usual Yeongam, 13 April: 15.3 µg/m³, 1.0× usual Yeongam, 14 April: 23.0 µg/m³, 1.5× usual Yeongam, 15 April: 21.8 µg/m³, 1.4× usual Yeonggwang Yeonggwang, 8 April: 6.9 µg/m³, 0.4× usual Yeonggwang, 9 April: 4.7 µg/m³, 0.3× usual Yeonggwang, 10 April: 10.9 µg/m³, 0.7× usual Yeonggwang, 11 April: 33.7 µg/m³, 2.2× usual Yeonggwang, 12 April: 34.8 µg/m³, 2.3× usual Yeonggwang, 13 April: 15.7 µg/m³, 1.0× usual Yeonggwang, 14 April: 17.6 µg/m³, 1.1× usual Yeonggwang, 15 April: 19.0 µg/m³, 1.2× usual Muan Muan, 8 April: 9.0 µg/m³, 0.6× usual Muan, 9 April: 7.8 µg/m³, 0.5× usual Muan, 10 April: 13.5 µg/m³, 0.9× usual Muan, 11 April: 30.2 µg/m³, 2.0× usual Muan, 12 April: 29.7 µg/m³, 2.0× usual Muan, 13 April: 15.3 µg/m³, 1.0× usual Muan, 14 April: 19.1 µg/m³, 1.3× usual Muan, 15 April: 19.4 µg/m³, 1.3× usual Naju Naju, 8 April: 5.6 µg/m³, 0.3× usual Naju, 9 April: 7.8 µg/m³, 0.4× usual Naju, 10 April: 16.3 µg/m³, 0.9× usual Naju, 11 April: 34.8 µg/m³, 2.0× usual Naju, 12 April: 41.0 µg/m³, 2.3× usual Naju, 13 April: 17.6 µg/m³, 1.0× usual Naju, 14 April: 27.4 µg/m³, 1.6× usual Naju, 15 April: 26.3 µg/m³, 1.5× usual Masan Masan, 8 April: 12.8 µg/m³, 0.7× usual Masan, 9 April: 11.6 µg/m³, 0.6× usual Masan, 10 April: 16.2 µg/m³, 0.9× usual Masan, 11 April: 35.1 µg/m³, 1.9× usual Masan, 12 April: 38.4 µg/m³, 2.1× usual Masan, 13 April: 19.1 µg/m³, 1.0× usual Masan, 14 April: 26.1 µg/m³, 1.4× usual Masan, 15 April: 27.2 µg/m³, 1.5× usual Gwangju Gwangju, 8 April: 10.5 µg/m³, 0.6× usual Gwangju, 9 April: 8.7 µg/m³, 0.5× usual Gwangju, 10 April: 15.9 µg/m³, 0.9× usual Gwangju, 11 April: 29.5 µg/m³, 1.7× usual Gwangju, 12 April: 35.5 µg/m³, 2.1× usual Gwangju, 13 April: 16.9 µg/m³, 1.0× usual Gwangju, 14 April: 21.6 µg/m³, 1.3× usual Gwangju, 15 April: 24.4 µg/m³, 1.4× usual Gaigeturi Gaigeturi, 8 April: 8.8 µg/m³, 0.5× usual Gaigeturi, 9 April: 11.2 µg/m³, 0.7× usual Gaigeturi, 10 April: 22.8 µg/m³, 1.4× usual Gaigeturi, 11 April: 31.6 µg/m³, 1.9× usual Gaigeturi, 12 April: 34.0 µg/m³, 2.0× usual Gaigeturi, 13 April: 13.6 µg/m³, 0.8× usual Gaigeturi, 14 April: 11.3 µg/m³, 0.7× usual Gaigeturi, 15 April: 16.9 µg/m³, 1.0× usual 8 Apr 9 10 11 12 13 14 15 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
Haenam Jeollanam-do, South Korea 1 11 April 17.3 2.4× Naju Jeollanam-do, South Korea 1 12 April 17.5 2.3× Koch'ang Jeollabuk-do, South Korea 1 11 April 16.1 2.3× Yeonggwang Jeollanam-do, South Korea 2 12 April 15.4 2.3× Yeongam Jeollanam-do, South Korea 2 11 April 15.1 2.3× Yŏnmu Chungcheongnam-do, South Korea 1 11 April 20.5 2.2× Jeonju Jeollabuk-do, South Korea 2 12 April 17.0 2.1× Gwangju Gwangju, South Korea 1 12 April 17.1 2.1× Masan Gwangju, South Korea 1 12 April 18.5 2.1× Gaigeturi Jeju-do, South Korea 1 12 April 16.6 2.0× Wanju Jeollabuk-do, South Korea 2 11 April 20.0 2.0× Muan Jeollanam-do, South Korea 1 11 April 15.1 2.0×
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 South Korea
Number 39 of 43 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, February 2026 147 South Korea, February 2025 132 South Korea, November 2025 128 South Korea, February 2026 121 South Korea, December 2025 113 South Korea, January 2025 113 South Korea, December 2025 107 South Korea, April 2026 12 Bars: cities reached; colour: the level of the episode's highest daily reading. All 43 .
Use this page SmogRank, South Korea, April 2026: 12 cities with PM2.5 at twice their usual or more, 11 to 12 April 2026, smogrank.com/episodes/2026-04-south-korea-2 (accessed 2 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.
