SmogRank / Episodes / United States

North-eastern United States and Canada, January 2026

For 1 day, on 6 January 2026, 11 cities in the United States and Canada had PM2.5 at least twice their usual for the time of year. The worst reading was Camden, New Jersey, United States: 33.6 µg/m³ on 6 January, about 3.1× its usual 10.9.

No cause namedWe have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached11in 2 countries
Days16 January 2026
Worst day6 January11 cities counted
Furthest above usual5.9×Nepean

Day by day

6 January 11 cities at twice their usual or more
UticaNewburghPittsfieldNew CitySyracuseDanburyScrantonPatersonWhite PlainsRutlandWaterburyFort LeeGreenfieldJersey CityNorth ChicopeeBridgeportNew York CitySpringfieldElizabethBayonneHartfordLindenNew HavenNew BrunswickBethlehemAllentownKeeneHolbrookCornwallEwingTrentonKingstonBensalemAbingtonNorristownToms RiverPennsaukenWorcesterNew LondonPhiladelphiaDorvalChesterSaint-Jean-sur-RichelieuSewellOttawaBrossardMontréalCoventryGatineauMilfordWilmingtonRochesterRivière-des-Prairies–Pointe-aux-TremblesFraminghamLaconiaDerryNewarkLowellBellevilleProvidenceBearPawtucketElktonHaverhillYorkBostonFall RiverQuincyBrocktonLynnPortsmouthSherbrookeHunt ValleyPeterboroughBuffaloPortlandHagerstownAltoonaLewistonSt. CatharinesJohnstownTorontoAugustaNewmarketMississaugaOakvilleBramptonHamiltonWaterdownMiltonBarrieAllistonWilkinsburgWest MifflinMcKeesportPittsburghCamdenLancasterHarrisburgLebanonReadingCarlisleAlbanyGranbyState CollegeNewtonNepean
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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

CamdenCamden, 3 January: 17.0 µg/m³, 1.6× usualCamden, 4 January: 19.1 µg/m³, 1.8× usualCamden, 5 January: 19.4 µg/m³, 1.8× usualCamden, 6 January: 33.6 µg/m³, 3.1× usualCamden, 7 January: 20.9 µg/m³, 1.9× usualCamden, 8 January: no readingCamden, 9 January: 16.6 µg/m³, 1.5× usualLebanonLebanon, 3 January: 11.9 µg/m³, 1.4× usualLebanon, 4 January: 12.7 µg/m³, 1.5× usualLebanon, 5 January: 15.8 µg/m³, 1.8× usualLebanon, 6 January: 32.2 µg/m³, 3.7× usualLebanon, 7 January: 26.2 µg/m³, 3.0× usualLebanon, 8 January: 13.6 µg/m³, 1.6× usualLebanon, 9 January: 17.6 µg/m³, 2.0× usualLancasterLancaster, 3 January: 13.8 µg/m³, 1.6× usualLancaster, 4 January: 14.6 µg/m³, 1.7× usualLancaster, 5 January: 15.5 µg/m³, 1.8× usualLancaster, 6 January: 31.9 µg/m³, 3.6× usualLancaster, 7 January: 20.6 µg/m³, 2.3× usualLancaster, 8 January: 18.1 µg/m³, 2.1× usualLancaster, 9 January: 16.3 µg/m³, 1.9× usualHarrisburgHarrisburg, 3 January: 11.7 µg/m³, 1.3× usualHarrisburg, 4 January: 11.6 µg/m³, 1.3× usualHarrisburg, 5 January: 16.8 µg/m³, 1.9× usualHarrisburg, 6 January: 31.3 µg/m³, 3.6× usualHarrisburg, 7 January: 16.4 µg/m³, 1.9× usualHarrisburg, 8 January: 13.0 µg/m³, 1.5× usualHarrisburg, 9 January: 19.0 µg/m³, 2.2× usualCarlisleCarlisle, 3 January: 12.7 µg/m³, 1.6× usualCarlisle, 4 January: 11.3 µg/m³, 1.4× usualCarlisle, 5 January: 19.0 µg/m³, 2.3× usualCarlisle, 6 January: 31.2 µg/m³, 3.9× usualCarlisle, 7 January: 14.7 µg/m³, 1.8× usualCarlisle, 8 January: 13.6 µg/m³, 1.7× usualCarlisle, 9 January: 18.3 µg/m³, 2.3× usualReadingReading, 3 January: 10.8 µg/m³, 1.3× usualReading, 4 January: 12.3 µg/m³, 1.5× usualReading, 5 January: 13.3 µg/m³, 1.6× usualReading, 6 January: 30.6 µg/m³, 3.8× usualReading, 7 January: 24.3 µg/m³, 3.0× usualReading, 8 January: 9.1 µg/m³, 1.1× usualReading, 9 January: 15.8 µg/m³, 2.0× usualNepeanNepean, 3 January: 1.6 µg/m³, 0.3× usualNepean, 4 January: 5.5 µg/m³, 1.1× usualNepean, 5 January: 13.2 µg/m³, 2.6× usualNepean, 6 January: 29.6 µg/m³, 5.9× usualNepean, 7 January: 28.6 µg/m³, 5.7× usualNepean, 8 January: 21.2 µg/m³, 4.2× usualNepean, 9 January: 17.1 µg/m³, 3.4× usualGranbyGranby, 3 January: 7.4 µg/m³, 1.0× usualGranby, 4 January: 10.0 µg/m³, 1.4× usualGranby, 5 January: 13.3 µg/m³, 1.9× usualGranby, 6 January: 29.1 µg/m³, 4.1× usualGranby, 7 January: 13.4 µg/m³, 1.9× usualGranby, 8 January: 17.5 µg/m³, 2.5× usualGranby, 9 January: 4.6 µg/m³, 0.6× usualState CollegeState College, 3 January: 9.4 µg/m³, 1.4× usualState College, 4 January: 8.6 µg/m³, 1.3× usualState College, 5 January: 14.5 µg/m³, 2.2× usualState College, 6 January: 29.0 µg/m³, 4.5× usualState College, 7 January: 8.7 µg/m³, 1.3× usualState College, 8 January: 9.4 µg/m³, 1.4× usualState College, 9 January: 10.2 µg/m³, 1.6× usualNewtonNewton, 3 January: 1.1 µg/m³, 0.2× usualNewton, 4 January: 1.4 µg/m³, 0.3× usualNewton, 5 January: 1.8 µg/m³, 0.4× usualNewton, 6 January: 28.8 µg/m³, 5.8× usualNewton, 7 January: 8.7 µg/m³, 1.7× usualNewton, 8 January: 6.4 µg/m³, 1.3× usualNewton, 9 January: 8.2 µg/m³, 1.6× usualAlbanyAlbany, 3 January: 6.1 µg/m³, 0.9× usualAlbany, 4 January: 5.9 µg/m³, 0.9× usualAlbany, 5 January: 11.8 µg/m³, 1.8× usualAlbany, 6 January: 27.1 µg/m³, 4.0× usualAlbany, 7 January: 13.9 µg/m³, 2.1× usualAlbany, 8 January: 13.9 µg/m³, 2.1× usualAlbany, 9 January: 15.2 µg/m³, 2.3× usual3 Jan456789
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
NepeanOntario, Canada1 29.66 January4.55.9×
NewtonMassachusetts, United States1 28.86 January4.75.8×
State CollegePennsylvania, United States1 29.06 January6.54.5×
GranbyQuebec, Canada1 29.16 January7.14.1×
AlbanyNew York, United States1 27.16 January6.74.0×
CarlislePennsylvania, United States1 31.26 January8.13.9×
ReadingPennsylvania, United States1 30.66 January8.13.8×
LebanonPennsylvania, United States1 32.26 January8.73.7×
LancasterPennsylvania, United States1 31.96 January8.83.6×
HarrisburgPennsylvania, United States1 31.36 January8.83.6×
CamdenNew Jersey, United States1 33.66 January10.93.1×

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 the United States and Canada

Number 71 of 106 episodes in the United States and Canada since our records began, by cities reached.

Bars: cities reached; colour: the level of the episode's highest daily reading. All 106.

Use this page

SmogRank, North-eastern United States and Canada, January 2026: 11 cities with PM2.5 at twice their usual or more, 6 January 2026, smogrank.com/episodes/2026-01-north-eastern-united-states-and-canada (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.