SmogRank / Episodes / India

North-eastern India, October 2025

For 3 days, from 23 to 25 October 2025, 10 cities in India had PM2.5 at least twice their usual for the time of year. The worst reading was Barbil, Odisha, India: 114.0 µg/m³ on 25 October, about 4.1× its usual 27.8.

No cause namedWe have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached10in 1 country
Days323 to 25 October 2025
Worst day23 October8 cities counted
Furthest above usual6.7×Aurangābād

Day by day

23 October 8 cities at twice their usual or more
GayaRājgīrSasarāmRourkelaArrahHājīpurJodaĀsansolChāpraRairangpurBuxarMungerRānīganjSamāstipurDurgapurMuzaffarpurBhāgalpurBelpaharSiwānSaharsaVaranasiBaripādaPurniaShrīrāmpurBilāspurHaldiaKolkataPrayagrajKishanganjSatnaMaiharPatnaBihār SharīfSingrauliArāriaKatiharBhelaiBarbilBegusaraiKeonjhargarhAurangābād
20 Oct2122232425262728
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

SingrauliSingrauli, 20 October: 102.0 µg/m³Singrauli, 21 October: 89.4 µg/m³Singrauli, 22 October: 48.9 µg/m³Singrauli, 23 October: 103.0 µg/m³, 2.1× its usual 48.3Singrauli, 24 October: 111.0 µg/m³, 2.1× its usual 52.7Singrauli, 25 October: 85.6 µg/m³Singrauli, 26 October: no readingSingrauli, 27 October: 59.2 µg/m³Singrauli, 28 October: 65.9 µg/m³BarbilBarbil, 20 October: 129.0 µg/m³Barbil, 21 October: 115.0 µg/m³Barbil, 22 October: 83.7 µg/m³Barbil, 23 October: 86.9 µg/m³, 3.2× its usual 27.3Barbil, 24 October: 83.8 µg/m³, 3.0× its usual 27.7Barbil, 25 October: 114.0 µg/m³, 4.1× its usual 27.8Barbil, 26 October: no readingBarbil, 27 October: 28.8 µg/m³Barbil, 28 October: 20.7 µg/m³PatnaPatna, 20 October: 85.7 µg/m³Patna, 21 October: 132.0 µg/m³Patna, 22 October: 79.2 µg/m³Patna, 23 October: 74.2 µg/m³, 2.0× its usual 37.0Patna, 24 October: 72.5 µg/m³Patna, 25 October: 48.2 µg/m³Patna, 26 October: no readingPatna, 27 October: 61.1 µg/m³Patna, 28 October: 48.9 µg/m³KeonjhargarhKeonjhargarh, 20 October: 29.5 µg/m³Keonjhargarh, 21 October: 54.0 µg/m³Keonjhargarh, 22 October: 97.4 µg/m³Keonjhargarh, 23 October: 69.2 µg/m³, 4.8× its usual 14.3Keonjhargarh, 24 October: 70.9 µg/m³, 4.7× its usual 15.0Keonjhargarh, 25 October: 68.1 µg/m³, 4.4× its usual 15.4Keonjhargarh, 26 October: no readingKeonjhargarh, 27 October: 55.3 µg/m³Keonjhargarh, 28 October: 11.6 µg/m³BegusaraiBegusarai, 20 October: 71.6 µg/m³Begusarai, 21 October: 87.9 µg/m³Begusarai, 22 October: 77.6 µg/m³Begusarai, 23 October: 66.4 µg/m³, 4.2× its usual 15.9Begusarai, 24 October: 66.4 µg/m³, 2.8× its usual 23.9Begusarai, 25 October: 66.2 µg/m³Begusarai, 26 October: no readingBegusarai, 27 October: 64.7 µg/m³Begusarai, 28 October: 66.6 µg/m³AurangābādAurangābād, 20 October: 26.6 µg/m³Aurangābād, 21 October: 80.7 µg/m³Aurangābād, 22 October: 61.2 µg/m³Aurangābād, 23 October: 57.6 µg/m³, 3.8× its usual 15.0Aurangābād, 24 October: 60.4 µg/m³, 6.7× its usual 9.0Aurangābād, 25 October: 54.0 µg/m³, 2.5× its usual 21.4Aurangābād, 26 October: no readingAurangābād, 27 October: 62.5 µg/m³Aurangābād, 28 October: 55.9 µg/m³KatiharKatihar, 20 October: 80.7 µg/m³Katihar, 21 October: 41.8 µg/m³Katihar, 22 October: 55.6 µg/m³Katihar, 23 October: 50.7 µg/m³, 2.4× its usual 21.5Katihar, 24 October: 48.7 µg/m³, 2.3× its usual 21.5Katihar, 25 October: 37.0 µg/m³Katihar, 26 October: no readingKatihar, 27 October: 30.4 µg/m³Katihar, 28 October: 24.2 µg/m³BhelaiBhelai, 20 October: 51.3 µg/m³Bhelai, 21 October: 38.4 µg/m³Bhelai, 22 October: 38.4 µg/m³Bhelai, 23 October: 38.4 µg/m³, 3.8× its usual 10.0Bhelai, 24 October: 38.4 µg/m³, 3.8× its usual 10.0Bhelai, 25 October: 38.4 µg/m³, 3.8× its usual 10.0Bhelai, 26 October: no readingBhelai, 27 October: 38.4 µg/m³Bhelai, 28 October: 38.4 µg/m³ArāriaArāria, 20 October: 62.4 µg/m³Arāria, 21 October: 102.0 µg/m³Arāria, 22 October: 60.7 µg/m³Arāria, 23 October: 63.7 µg/m³Arāria, 24 October: 48.9 µg/m³Arāria, 25 October: 72.9 µg/m³, 2.2× its usual 33.6Arāria, 26 October: no readingArāria, 27 October: 50.3 µg/m³Arāria, 28 October: 51.3 µg/m³Bihār SharīfBihār Sharīf, 20 October: no readingBihār Sharīf, 21 October: 129.0 µg/m³Bihār Sharīf, 22 October: 79.5 µg/m³Bihār Sharīf, 23 October: 61.8 µg/m³Bihār Sharīf, 24 October: 67.6 µg/m³Bihār Sharīf, 25 October: 71.9 µg/m³, 2.1× its usual 34.0Bihār Sharīf, 26 October: no readingBihār Sharīf, 27 October: 88.0 µg/m³Bihār Sharīf, 28 October: 67.9 µg/m³20 Oct2122232425262728
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
AurangābādBihar, India3 60.424 October9.06.7×
KeonjhargarhOdisha, India3 70.924 October15.04.7×
BegusaraiBihar, India2 66.423 October15.94.2×
BarbilOdisha, India3 114.025 October27.84.1×
BhelaiChhattisgarh, India3 38.423 October10.03.8×
KatiharBihar, India2 50.723 October21.52.4×
ArāriaBihar, India1 72.925 October33.62.2×
SingrauliMadhya Pradesh, India2 111.024 October52.72.1×
Bihār SharīfBihar, India1 71.925 October34.02.1×
PatnaBihar, India1 74.223 October37.02.0×

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 India

Number 40 of 54 episodes in India since our records began, by cities reached.

Bars: cities reached; colour: the level of the episode's highest daily reading. All 54.

Use this page

SmogRank, North-eastern India, October 2025: 10 cities with PM2.5 at twice their usual or more, 23 to 25 October 2025, smogrank.com/episodes/2025-10-north-eastern-india (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.