SmogRank / Episodes / United States

Oklahoma and Arkansas, United States, January 2026

For 2 days, from 28 to 29 January 2026, 8 cities in the United States had PM2.5 at least twice their usual for the time of year. The worst reading was Moore, Oklahoma, United States: 37.3 µg/m³ on 28 January, about 5.7× its usual 6.6.

No cause namedWe have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached8in 1 country
Days228 to 29 January 2026
Worst day28 January8 cities counted
Furthest above usual5.7×Lawton

Day by day

28 January 8 cities at twice their usual or more
JenksPonca CityDentonSaginawSpringdaleWichitaTexarkanaShreveportSpringfieldLittle RockDodge CityMonroeFort WorthEdmondOklahoma CityDerbyFort SmithMcAlesterMooreLawton
25 Jan2627282930311 Feb
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

MooreMoore, 25 January: 6.5 µg/m³, 1.0× usualMoore, 26 January: 12.3 µg/m³, 1.9× usualMoore, 27 January: 17.4 µg/m³, 2.6× usualMoore, 28 January: 37.3 µg/m³, 5.7× usualMoore, 29 January: 27.8 µg/m³, 4.2× usualMoore, 30 January: 15.1 µg/m³, 2.3× usualMoore, 31 January: 7.8 µg/m³, 1.2× usualMoore, 1 February: 11.6 µg/m³, 1.8× usualMcAlesterMcAlester, 25 January: 7.6 µg/m³, 1.1× usualMcAlester, 26 January: 16.6 µg/m³, 2.4× usualMcAlester, 27 January: 16.6 µg/m³, 2.4× usualMcAlester, 28 January: 36.9 µg/m³, 5.3× usualMcAlester, 29 January: 30.1 µg/m³, 4.3× usualMcAlester, 30 January: 15.5 µg/m³, 2.2× usualMcAlester, 31 January: 8.5 µg/m³, 1.2× usualMcAlester, 1 February: 14.2 µg/m³, 2.0× usualOklahoma CityOklahoma City, 25 January: 5.9 µg/m³, 0.8× usualOklahoma City, 26 January: 11.5 µg/m³, 1.6× usualOklahoma City, 27 January: 17.7 µg/m³, 2.5× usualOklahoma City, 28 January: 31.4 µg/m³, 4.5× usualOklahoma City, 29 January: 24.6 µg/m³, 3.5× usualOklahoma City, 30 January: 14.2 µg/m³, 2.0× usualOklahoma City, 31 January: 8.3 µg/m³, 1.2× usualOklahoma City, 1 February: 9.3 µg/m³, 1.3× usualFort SmithFort Smith, 25 January: 8.6 µg/m³, 1.3× usualFort Smith, 26 January: 12.5 µg/m³, 2.0× usualFort Smith, 27 January: 16.3 µg/m³, 2.5× usualFort Smith, 28 January: 29.8 µg/m³, 4.7× usualFort Smith, 29 January: 28.5 µg/m³, 4.5× usualFort Smith, 30 January: 10.5 µg/m³, 1.6× usualFort Smith, 31 January: 5.9 µg/m³, 0.9× usualFort Smith, 1 February: 8.0 µg/m³, 1.3× usualLawtonLawton, 25 January: 3.9 µg/m³, 0.8× usualLawton, 26 January: 7.7 µg/m³, 1.5× usualLawton, 27 January: 12.1 µg/m³, 2.4× usualLawton, 28 January: 29.1 µg/m³, 5.7× usualLawton, 29 January: 24.5 µg/m³, 4.8× usualLawton, 30 January: 16.4 µg/m³, 3.2× usualLawton, 31 January: 7.8 µg/m³, 1.5× usualLawton, 1 February: 10.8 µg/m³, 2.1× usualEdmondEdmond, 25 January: 5.9 µg/m³, 0.9× usualEdmond, 26 January: 9.7 µg/m³, 1.5× usualEdmond, 27 January: 16.6 µg/m³, 2.6× usualEdmond, 28 January: 27.6 µg/m³, 4.3× usualEdmond, 29 January: 21.5 µg/m³, 3.4× usualEdmond, 30 January: 12.7 µg/m³, 2.0× usualEdmond, 31 January: 7.3 µg/m³, 1.1× usualEdmond, 1 February: 9.2 µg/m³, 1.4× usualFort WorthFort Worth, 25 January: 4.4 µg/m³, 0.6× usualFort Worth, 26 January: 15.0 µg/m³, 2.1× usualFort Worth, 27 January: 10.5 µg/m³, 1.5× usualFort Worth, 28 January: 26.0 µg/m³, 3.7× usualFort Worth, 29 January: 15.0 µg/m³, 2.1× usualFort Worth, 30 January: 17.2 µg/m³, 2.5× usualFort Worth, 31 January: 8.0 µg/m³, 1.1× usualFort Worth, 1 February: 16.3 µg/m³, 2.3× usualDerbyDerby, 25 January: 7.5 µg/m³, 1.3× usualDerby, 26 January: 11.1 µg/m³, 1.9× usualDerby, 27 January: 14.3 µg/m³, 2.5× usualDerby, 28 January: 25.4 µg/m³, 4.5× usualDerby, 29 January: 25.1 µg/m³, 4.4× usualDerby, 30 January: 11.9 µg/m³, 2.1× usualDerby, 31 January: 7.0 µg/m³, 1.2× usualDerby, 1 February: 10.3 µg/m³, 1.8× usual25 Jan2627282930311 Feb
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
LawtonOklahoma, United States1 29.128 January5.15.7×
MooreOklahoma, United States2 37.328 January6.65.7×
McAlesterOklahoma, United States2 36.928 January7.05.3×
Fort SmithArkansas, United States2 29.828 January6.44.7×
Oklahoma CityOklahoma, United States1 31.428 January7.04.5×
DerbyKansas, United States2 25.428 January5.74.5×
EdmondOklahoma, United States1 27.628 January6.44.3×
Fort WorthTexas, United States1 26.028 January7.03.7×

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

Number 89 of 98 episodes in the United States since our records began, by cities reached.

Bars: cities reached; colour: the level of the episode's highest daily reading. All 98.

Use this page

SmogRank, Oklahoma and Arkansas, United States, January 2026: 8 cities with PM2.5 at twice their usual or more, 28 to 29 January 2026, smogrank.com/episodes/2026-01-oklahoma-and-arkansas-united-states (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.