SmogRank / Episodes / United States

North-eastern United States and Canada, 2 February 2026

For 1 day, on 2 February 2026, 13 cities in the United States and Canada had PM2.5 at least twice their usual for the time of year. The worst reading was Redford, Michigan, United States: 32.6 µg/m³ on 2 February, about 2.5× its usual 13.3.

No cause namedWe have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached13in 2 countries
Days12 February 2026
Worst day2 February13 cities counted
Furthest above usual4.2×Sarnia

Day by day

2 February 13 cities at twice their usual or more
ClevelandCleveland HeightsShaker HeightsMedinaPainesvilleAkronChathamCantonWarrenSt. ThomasYoungstownHermitageLondonTaylorWeirtonSteubenvilleErieWeirton HeightsPerrysburgYpsilantiWestervilleGahannaDublinColumbusBrantfordUpper Saint ClairKitchenerPittsburghWilkinsburgMcKeesportGuelphLimaHamiltonWaterdownSpringfieldMiltonOakvilleBay CityBramptonMississaugaLansingSt. CatharinesDaytonTorontoBuffaloJohnstownLebanonNewmarketFort WayneMiddletownMasonAltoonaKalamazooMuncieState CollegeGrand RapidsWyomingElkhartJenisonAndersonRochesterSouth BendHollandKokomoFishersHagerstownIndianapolisCarlisleMichigan CityHarrisburgLafayetteYorkPortageLebanonHunt ValleyBaltimoreEssexWindsorRedfordDearbornLincoln ParkOregonToledoDetroitEastpointePort HuronSouthfieldWest MifflinAnn ArborSarnia
30 Jan311 Feb2345
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

RedfordRedford, 30 January: 10.7 µg/m³Redford, 31 January: 8.1 µg/m³Redford, 1 February: 17.8 µg/m³Redford, 2 February: 32.6 µg/m³, 2.5× its usual 13.3Redford, 3 February: 18.8 µg/m³Redford, 4 February: 10.3 µg/m³Redford, 5 February: 22.5 µg/m³Ann ArborAnn Arbor, 30 January: 4.6 µg/m³Ann Arbor, 31 January: 4.7 µg/m³Ann Arbor, 1 February: 7.8 µg/m³Ann Arbor, 2 February: 32.1 µg/m³, 3.9× its usual 8.2Ann Arbor, 3 February: 15.7 µg/m³Ann Arbor, 4 February: no readingAnn Arbor, 5 February: 17.4 µg/m³West MifflinWest Mifflin, 30 January: 4.3 µg/m³West Mifflin, 31 January: 42.7 µg/m³West Mifflin, 1 February: 5.9 µg/m³West Mifflin, 2 February: 32.0 µg/m³, 3.9× its usual 8.3West Mifflin, 3 February: 11.9 µg/m³West Mifflin, 4 February: 7.8 µg/m³West Mifflin, 5 February: 12.6 µg/m³SarniaSarnia, 30 January: 3.8 µg/m³Sarnia, 31 January: 2.2 µg/m³Sarnia, 1 February: 5.6 µg/m³Sarnia, 2 February: 28.0 µg/m³, 4.2× its usual 6.7Sarnia, 3 February: 11.0 µg/m³Sarnia, 4 February: 4.2 µg/m³Sarnia, 5 February: 14.0 µg/m³DetroitDetroit, 30 January: 6.8 µg/m³Detroit, 31 January: 4.1 µg/m³Detroit, 1 February: 7.5 µg/m³Detroit, 2 February: 27.5 µg/m³, 3.1× its usual 8.9Detroit, 3 February: 14.3 µg/m³Detroit, 4 February: 5.6 µg/m³Detroit, 5 February: 16.8 µg/m³Port HuronPort Huron, 30 January: 4.0 µg/m³Port Huron, 31 January: 2.2 µg/m³Port Huron, 1 February: 7.6 µg/m³Port Huron, 2 February: 27.3 µg/m³, 3.8× its usual 7.1Port Huron, 3 February: 11.1 µg/m³Port Huron, 4 February: 5.0 µg/m³Port Huron, 5 February: 14.7 µg/m³ToledoToledo, 30 January: 6.0 µg/m³Toledo, 31 January: 6.5 µg/m³Toledo, 1 February: 11.2 µg/m³Toledo, 2 February: 26.7 µg/m³, 3.1× its usual 8.6Toledo, 3 February: 19.0 µg/m³Toledo, 4 February: 8.6 µg/m³Toledo, 5 February: 17.0 µg/m³DearbornDearborn, 30 January: 7.9 µg/m³Dearborn, 31 January: 4.0 µg/m³Dearborn, 1 February: 7.3 µg/m³Dearborn, 2 February: 26.7 µg/m³, 2.8× its usual 9.5Dearborn, 3 February: 14.4 µg/m³Dearborn, 4 February: 6.0 µg/m³Dearborn, 5 February: 15.0 µg/m³EastpointeEastpointe, 30 January: 5.2 µg/m³Eastpointe, 31 January: 3.1 µg/m³Eastpointe, 1 February: 6.9 µg/m³Eastpointe, 2 February: 26.1 µg/m³, 3.6× its usual 7.2Eastpointe, 3 February: 12.6 µg/m³Eastpointe, 4 February: 4.9 µg/m³Eastpointe, 5 February: 14.4 µg/m³OregonOregon, 30 January: 4.1 µg/m³Oregon, 31 January: 4.4 µg/m³Oregon, 1 February: 9.4 µg/m³Oregon, 2 February: 26.0 µg/m³, 2.9× its usual 9.1Oregon, 3 February: 17.6 µg/m³Oregon, 4 February: 6.8 µg/m³Oregon, 5 February: 16.6 µg/m³Lincoln ParkLincoln Park, 30 January: 5.8 µg/m³Lincoln Park, 31 January: 3.9 µg/m³Lincoln Park, 1 February: 7.1 µg/m³Lincoln Park, 2 February: 25.4 µg/m³, 2.9× its usual 8.7Lincoln Park, 3 February: 14.2 µg/m³Lincoln Park, 4 February: 4.8 µg/m³Lincoln Park, 5 February: 13.6 µg/m³SouthfieldSouthfield, 30 January: 4.8 µg/m³Southfield, 31 January: 3.2 µg/m³Southfield, 1 February: 6.1 µg/m³Southfield, 2 February: 25.3 µg/m³, 3.9× its usual 6.5Southfield, 3 February: 11.9 µg/m³Southfield, 4 February: 4.0 µg/m³Southfield, 5 February: 12.7 µg/m³WindsorWindsor, 30 January: 6.3 µg/m³Windsor, 31 January: 4.3 µg/m³Windsor, 1 February: 8.9 µg/m³Windsor, 2 February: 25.2 µg/m³, 2.5× its usual 10.0Windsor, 3 February: 17.5 µg/m³Windsor, 4 February: 6.1 µg/m³Windsor, 5 February: 17.9 µg/m³30 Jan311 Feb2345
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
SarniaOntario, Canada1 28.02 February6.74.2×
Ann ArborMichigan, United States1 32.12 February8.23.9×
West MifflinPennsylvania, United States1 32.02 February8.33.9×
SouthfieldMichigan, United States1 25.32 February6.53.9×
Port HuronMichigan, United States1 27.32 February7.13.8×
EastpointeMichigan, United States1 26.12 February7.23.6×
DetroitMichigan, United States1 27.52 February8.93.1×
ToledoOhio, United States1 26.72 February8.63.1×
OregonOhio, United States1 26.02 February9.12.9×
Lincoln ParkMichigan, United States1 25.42 February8.72.9×
DearbornMichigan, United States1 26.72 February9.52.8×
RedfordMichigan, United States1 32.62 February13.32.5×
WindsorOntario, Canada1 25.22 February10.02.5×

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 the United States and Canada

Number 81 of 141 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 141.

Use this page

SmogRank, North-eastern United States and Canada, 2 February 2026: 13 cities with PM2.5 at twice their usual or more, 2 February 2026, smogrank.com/episodes/2026-02-02-north-eastern-united-states-and-canada (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.