SmogRank / Episodes / United States

United States and Mexico, March 2025

For 2 days, from 14 to 15 March 2025, 42 cities in the United States and Mexico had PM2.5 at least twice their usual for the time of year. The worst reading was Chanute, Kansas, United States: 77.6 µg/m³ on 14 March, about 9.2× its usual 8.4. Ended 15 March.

No cause namedWe have no fire or smoke records for these days, so we only say what the measurements show.
Cities reached42in 2 countries
Days214 to 15 March 2025
Worst day14 March40 cities counted
Furthest above usual11×Lubbock

Day by day

14 March 40 cities at twice their usual or more
BeltonCorsicanaTaylorWells BranchAustinCollege StationSan MarcosLockhartTimberwood ParkLive OakHelotesWindcrestSan AntonioMissouri CityTexarkanaHighlandsBaytownLa PorteSeabrookShreveportEagle PassGalvestonPort ArthurLaredoDodge CityLamarCiudad General EscobedoRaymoreGarcíaMonterreyJardines de la SillaSanta CatarinaBeatriceLincolnCiudad Benito JuárezCadereyta JiménezHoustonMissionPasadenaCorpus ChristiConroeLacy-LakeviewMission BendPort IsabelWichitaSpringdaleHeroica MatamorosSaint JosephOklahoma CityHaysvilleDerbyTopekaMiamiKaufmanSaginawRiver OaksMooreFort SmithMcAlesterJenksGlenpoolPonca CityTulsaKansas CityLawtonKansas CityEdmondLibertyKearneyFort WorthOlatheOdessaLeawoodDentonChanuteLubbock
11 Mar12131415161718
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

ChanuteChanute, 11 March: 8.3 µg/m³Chanute, 12 March: 9.0 µg/m³Chanute, 13 March: 16.6 µg/m³Chanute, 14 March: 77.6 µg/m³, 9.2× its usual 8.4Chanute, 15 March: 6.3 µg/m³Chanute, 16 March: 6.9 µg/m³Chanute, 17 March: 8.0 µg/m³Chanute, 18 March: 9.1 µg/m³DentonDenton, 11 March: 4.5 µg/m³Denton, 12 March: 6.6 µg/m³Denton, 13 March: 7.1 µg/m³Denton, 14 March: 63.0 µg/m³, 9.0× its usual 7.0Denton, 15 March: 31.1 µg/m³Denton, 16 March: 2.9 µg/m³Denton, 17 March: no readingDenton, 18 March: 6.2 µg/m³TulsaTulsa, 11 March: 6.7 µg/m³Tulsa, 12 March: 9.9 µg/m³Tulsa, 13 March: 17.8 µg/m³Tulsa, 14 March: 60.9 µg/m³, 6.2× its usual 9.8Tulsa, 15 March: 36.8 µg/m³Tulsa, 16 March: 15.1 µg/m³Tulsa, 17 March: 10.1 µg/m³Tulsa, 18 March: 12.0 µg/m³Fort WorthFort Worth, 11 March: 4.5 µg/m³Fort Worth, 12 March: 9.3 µg/m³Fort Worth, 13 March: 8.8 µg/m³Fort Worth, 14 March: 60.1 µg/m³, 7.5× its usual 8.0Fort Worth, 15 March: 47.8 µg/m³Fort Worth, 16 March: 3.0 µg/m³Fort Worth, 17 March: 4.9 µg/m³Fort Worth, 18 March: 7.3 µg/m³OlatheOlathe, 11 March: 9.8 µg/m³Olathe, 12 March: 13.7 µg/m³Olathe, 13 March: 17.6 µg/m³Olathe, 14 March: 57.5 µg/m³, 7.7× its usual 7.5Olathe, 15 March: 19.1 µg/m³Olathe, 16 March: 3.6 µg/m³Olathe, 17 March: 6.1 µg/m³Olathe, 18 March: 9.5 µg/m³LubbockLubbock, 11 March: 3.4 µg/m³Lubbock, 12 March: 5.3 µg/m³Lubbock, 13 March: 3.5 µg/m³Lubbock, 14 March: 57.0 µg/m³, 11× its usual 4.4Lubbock, 15 March: 3.8 µg/m³Lubbock, 16 March: 1.8 µg/m³Lubbock, 17 March: 8.7 µg/m³Lubbock, 18 March: 77.8 µg/m³EdmondEdmond, 11 March: 4.4 µg/m³Edmond, 12 March: 8.0 µg/m³Edmond, 13 March: 9.1 µg/m³Edmond, 14 March: 56.2 µg/m³, 7.4× its usual 7.6Edmond, 15 March: 9.6 µg/m³Edmond, 16 March: 3.5 µg/m³Edmond, 17 March: 4.3 µg/m³Edmond, 18 March: 9.1 µg/m³GlenpoolGlenpool, 11 March: 8.4 µg/m³Glenpool, 12 March: 10.4 µg/m³Glenpool, 13 March: 14.9 µg/m³Glenpool, 14 March: 54.2 µg/m³, 5.9× its usual 9.2Glenpool, 15 March: 28.7 µg/m³Glenpool, 16 March: 4.6 µg/m³Glenpool, 17 March: 8.3 µg/m³Glenpool, 18 March: 7.7 µg/m³JenksJenks, 11 March: 8.4 µg/m³Jenks, 12 March: 10.4 µg/m³Jenks, 13 March: 14.9 µg/m³Jenks, 14 March: 54.2 µg/m³, 5.9× its usual 9.2Jenks, 15 March: 28.7 µg/m³Jenks, 16 March: 4.6 µg/m³Jenks, 17 March: 8.3 µg/m³Jenks, 18 March: 7.7 µg/m³OdessaOdessa, 11 March: 6.8 µg/m³Odessa, 12 March: 13.8 µg/m³Odessa, 13 March: 7.0 µg/m³Odessa, 14 March: 52.9 µg/m³, 7.8× its usual 6.8Odessa, 15 March: 10.4 µg/m³Odessa, 16 March: 3.6 µg/m³Odessa, 17 March: no readingOdessa, 18 March: 98.5 µg/m³Kansas CityKansas City, 11 March: 10.3 µg/m³Kansas City, 12 March: 18.2 µg/m³Kansas City, 13 March: 17.7 µg/m³Kansas City, 14 March: 52.9 µg/m³, 6.5× its usual 8.2Kansas City, 15 March: 20.9 µg/m³Kansas City, 16 March: 7.0 µg/m³Kansas City, 17 March: 6.5 µg/m³Kansas City, 18 March: 8.2 µg/m³Ponca CityPonca City, 11 March: 5.2 µg/m³Ponca City, 12 March: 8.9 µg/m³Ponca City, 13 March: 14.6 µg/m³Ponca City, 14 March: 51.3 µg/m³, 6.0× its usual 8.6Ponca City, 15 March: 3.4 µg/m³Ponca City, 16 March: 3.8 µg/m³Ponca City, 17 March: 6.1 µg/m³Ponca City, 18 March: 9.2 µg/m³McAlesterMcAlester, 11 March: 4.9 µg/m³McAlester, 12 March: 6.1 µg/m³McAlester, 13 March: 8.2 µg/m³McAlester, 14 March: 46.5 µg/m³, 5.9× its usual 7.9McAlester, 15 March: 34.2 µg/m³McAlester, 16 March: 5.3 µg/m³McAlester, 17 March: 6.1 µg/m³McAlester, 18 March: 6.1 µg/m³MiamiMiami, 11 March: 8.5 µg/m³Miami, 12 March: 21.5 µg/m³Miami, 13 March: 22.6 µg/m³Miami, 14 March: 46.1 µg/m³, 5.1× its usual 9.1Miami, 15 March: 12.0 µg/m³Miami, 16 March: 5.9 µg/m³Miami, 17 March: no readingMiami, 18 March: 10.7 µg/m³MooreMoore, 11 March: 5.1 µg/m³Moore, 12 March: 8.0 µg/m³Moore, 13 March: 9.0 µg/m³Moore, 14 March: 45.9 µg/m³, 5.5× its usual 8.4Moore, 15 March: 7.2 µg/m³Moore, 16 March: 3.4 µg/m³Moore, 17 March: 4.4 µg/m³Moore, 18 March: 8.9 µg/m³Fort SmithFort Smith, 11 March: 6.8 µg/m³Fort Smith, 12 March: 9.4 µg/m³Fort Smith, 13 March: 10.9 µg/m³Fort Smith, 14 March: 45.3 µg/m³, 5.6× its usual 8.1Fort Smith, 15 March: no readingFort Smith, 16 March: no readingFort Smith, 17 March: 6.8 µg/m³Fort Smith, 18 March: 7.1 µg/m³LawtonLawton, 11 March: no readingLawton, 12 March: no readingLawton, 13 March: no readingLawton, 14 March: 44.4 µg/m³, 6.5× its usual 6.8Lawton, 15 March: 6.1 µg/m³Lawton, 16 March: 2.8 µg/m³Lawton, 17 March: 3.6 µg/m³Lawton, 18 March: 9.8 µg/m³LeawoodLeawood, 11 March: 8.7 µg/m³Leawood, 12 March: 13.7 µg/m³Leawood, 13 March: 14.0 µg/m³Leawood, 14 March: 44.2 µg/m³, 8.3× its usual 5.3Leawood, 15 March: 20.0 µg/m³Leawood, 16 March: 2.4 µg/m³Leawood, 17 March: 4.6 µg/m³Leawood, 18 March: 8.9 µg/m³Oklahoma CityOklahoma City, 11 March: 5.1 µg/m³Oklahoma City, 12 March: 8.8 µg/m³Oklahoma City, 13 March: 10.2 µg/m³Oklahoma City, 14 March: 43.0 µg/m³, 5.0× its usual 8.6Oklahoma City, 15 March: 9.3 µg/m³Oklahoma City, 16 March: 3.5 µg/m³Oklahoma City, 17 March: 5.5 µg/m³Oklahoma City, 18 March: 8.4 µg/m³Kansas CityKansas City, 11 March: 8.1 µg/m³Kansas City, 12 March: 16.0 µg/m³Kansas City, 13 March: 16.0 µg/m³Kansas City, 14 March: 42.6 µg/m³, 6.4× its usual 6.7Kansas City, 15 March: 19.5 µg/m³Kansas City, 16 March: 2.9 µg/m³Kansas City, 17 March: 5.1 µg/m³Kansas City, 18 March: 7.3 µg/m³Heroica MatamorosHeroica Matamoros, 11 March: 4.7 µg/m³Heroica Matamoros, 12 March: 9.0 µg/m³Heroica Matamoros, 13 March: 21.5 µg/m³Heroica Matamoros, 14 March: 41.6 µg/m³, 4.1× its usual 10.2Heroica Matamoros, 15 March: 36.3 µg/m³, 3.6× its usual 10.1Heroica Matamoros, 16 March: 18.9 µg/m³Heroica Matamoros, 17 March: 10.2 µg/m³Heroica Matamoros, 18 March: 8.0 µg/m³TopekaTopeka, 11 March: 9.4 µg/m³Topeka, 12 March: 14.4 µg/m³Topeka, 13 March: 17.3 µg/m³Topeka, 14 March: 40.6 µg/m³, 5.1× its usual 8.0Topeka, 15 March: 8.2 µg/m³Topeka, 16 March: 6.2 µg/m³Topeka, 17 March: 8.2 µg/m³Topeka, 18 March: 9.4 µg/m³Port IsabelPort Isabel, 11 March: 2.1 µg/m³Port Isabel, 12 March: 7.2 µg/m³Port Isabel, 13 March: 14.3 µg/m³Port Isabel, 14 March: 39.2 µg/m³, 2.8× its usual 14.2Port Isabel, 15 March: 48.7 µg/m³, 3.4× its usual 14.3Port Isabel, 16 March: 20.5 µg/m³Port Isabel, 17 March: 4.6 µg/m³Port Isabel, 18 March: 10.0 µg/m³River OaksRiver Oaks, 11 March: 4.7 µg/m³River Oaks, 12 March: 7.2 µg/m³River Oaks, 13 March: 5.0 µg/m³River Oaks, 14 March: 39.1 µg/m³, 5.2× its usual 7.5River Oaks, 15 March: 28.1 µg/m³River Oaks, 16 March: 4.0 µg/m³River Oaks, 17 March: 5.0 µg/m³River Oaks, 18 March: 5.7 µg/m³SaginawSaginaw, 11 March: 4.7 µg/m³Saginaw, 12 March: 7.2 µg/m³Saginaw, 13 March: 5.0 µg/m³Saginaw, 14 March: 39.1 µg/m³, 5.2× its usual 7.5Saginaw, 15 March: 28.1 µg/m³Saginaw, 16 March: 4.0 µg/m³Saginaw, 17 March: 5.0 µg/m³Saginaw, 18 March: 5.7 µg/m³DerbyDerby, 11 March: 7.0 µg/m³Derby, 12 March: 14.7 µg/m³Derby, 13 March: 16.5 µg/m³Derby, 14 March: 39.1 µg/m³, 5.1× its usual 7.6Derby, 15 March: 3.2 µg/m³Derby, 16 March: 3.9 µg/m³Derby, 17 March: 6.1 µg/m³Derby, 18 March: 12.5 µg/m³HaysvilleHaysville, 11 March: 7.0 µg/m³Haysville, 12 March: 14.7 µg/m³Haysville, 13 March: 16.5 µg/m³Haysville, 14 March: 39.1 µg/m³, 5.1× its usual 7.6Haysville, 15 March: 3.2 µg/m³Haysville, 16 March: 3.9 µg/m³Haysville, 17 March: 6.1 µg/m³Haysville, 18 March: 12.5 µg/m³KearneyKearney, 11 March: 8.1 µg/m³Kearney, 12 March: 9.0 µg/m³Kearney, 13 March: 13.2 µg/m³Kearney, 14 March: 38.8 µg/m³, 7.5× its usual 5.2Kearney, 15 March: 22.2 µg/m³Kearney, 16 March: 2.8 µg/m³Kearney, 17 March: 4.4 µg/m³Kearney, 18 March: 7.2 µg/m³LibertyLiberty, 11 March: 8.1 µg/m³Liberty, 12 March: 9.0 µg/m³Liberty, 13 March: 13.2 µg/m³Liberty, 14 March: 38.8 µg/m³, 7.5× its usual 5.2Liberty, 15 March: 22.2 µg/m³Liberty, 16 March: 2.8 µg/m³Liberty, 17 March: 4.4 µg/m³Liberty, 18 March: 7.2 µg/m³KaufmanKaufman, 11 March: 4.6 µg/m³Kaufman, 12 March: 6.3 µg/m³Kaufman, 13 March: 8.6 µg/m³Kaufman, 14 March: 36.6 µg/m³, 5.2× its usual 7.1Kaufman, 15 March: 57.0 µg/m³Kaufman, 16 March: 2.9 µg/m³Kaufman, 17 March: 4.8 µg/m³Kaufman, 18 March: 5.7 µg/m³Cadereyta JiménezCadereyta Jiménez, 11 March: 25.9 µg/m³Cadereyta Jiménez, 12 March: no readingCadereyta Jiménez, 13 March: 27.3 µg/m³Cadereyta Jiménez, 14 March: 35.6 µg/m³, 2.3× its usual 15.7Cadereyta Jiménez, 15 March: 32.5 µg/m³, 2.1× its usual 15.6Cadereyta Jiménez, 16 March: 28.6 µg/m³Cadereyta Jiménez, 17 March: 25.1 µg/m³Cadereyta Jiménez, 18 March: 19.9 µg/m³SpringdaleSpringdale, 11 March: 5.9 µg/m³Springdale, 12 March: 11.8 µg/m³Springdale, 13 March: 16.0 µg/m³Springdale, 14 March: 34.1 µg/m³, 3.8× its usual 8.9Springdale, 15 March: 51.5 µg/m³Springdale, 16 March: 7.7 µg/m³Springdale, 17 March: 8.2 µg/m³Springdale, 18 March: 15.6 µg/m³WichitaWichita, 11 March: 9.8 µg/m³Wichita, 12 March: 15.3 µg/m³Wichita, 13 March: 19.7 µg/m³Wichita, 14 March: 33.5 µg/m³, 3.7× its usual 9.0Wichita, 15 March: 3.9 µg/m³Wichita, 16 March: 4.6 µg/m³Wichita, 17 March: 5.7 µg/m³Wichita, 18 March: 11.5 µg/m³Saint JosephSaint Joseph, 11 March: 7.4 µg/m³Saint Joseph, 12 March: 12.9 µg/m³Saint Joseph, 13 March: 23.4 µg/m³Saint Joseph, 14 March: 32.1 µg/m³, 4.4× its usual 7.3Saint Joseph, 15 March: 18.1 µg/m³Saint Joseph, 16 March: no readingSaint Joseph, 17 March: 6.5 µg/m³Saint Joseph, 18 March: 16.6 µg/m³Corpus ChristiCorpus Christi, 11 March: 5.8 µg/m³Corpus Christi, 12 March: 8.0 µg/m³Corpus Christi, 13 March: 20.3 µg/m³Corpus Christi, 14 March: 30.1 µg/m³, 2.7× its usual 11.1Corpus Christi, 15 March: 21.6 µg/m³Corpus Christi, 16 March: 7.4 µg/m³Corpus Christi, 17 March: 6.9 µg/m³Corpus Christi, 18 March: 10.5 µg/m³ConroeConroe, 11 March: 9.2 µg/m³Conroe, 12 March: 7.8 µg/m³Conroe, 13 March: 14.2 µg/m³Conroe, 14 March: 29.9 µg/m³, 2.9× its usual 10.2Conroe, 15 March: 34.7 µg/m³Conroe, 16 March: 8.2 µg/m³Conroe, 17 March: 23.0 µg/m³Conroe, 18 March: 6.7 µg/m³Mission BendMission Bend, 11 March: 4.0 µg/m³Mission Bend, 12 March: 5.7 µg/m³Mission Bend, 13 March: 16.9 µg/m³Mission Bend, 14 March: 28.0 µg/m³, 3.0× its usual 9.4Mission Bend, 15 March: 25.0 µg/m³Mission Bend, 16 March: 3.4 µg/m³Mission Bend, 17 March: 4.3 µg/m³Mission Bend, 18 March: 5.4 µg/m³HoustonHouston, 11 March: 9.8 µg/m³Houston, 12 March: 10.1 µg/m³Houston, 13 March: 19.0 µg/m³Houston, 14 March: 27.9 µg/m³, 2.4× its usual 11.5Houston, 15 March: 30.9 µg/m³Houston, 16 March: 4.8 µg/m³Houston, 17 March: 9.5 µg/m³Houston, 18 March: 7.5 µg/m³Lacy-LakeviewLacy-Lakeview, 11 March: 10.1 µg/m³Lacy-Lakeview, 12 March: 8.2 µg/m³Lacy-Lakeview, 13 March: 9.3 µg/m³Lacy-Lakeview, 14 March: 27.7 µg/m³, 3.0× its usual 9.1Lacy-Lakeview, 15 March: 56.7 µg/m³Lacy-Lakeview, 16 March: 6.2 µg/m³Lacy-Lakeview, 17 March: 6.9 µg/m³Lacy-Lakeview, 18 March: 9.1 µg/m³PasadenaPasadena, 11 March: 6.6 µg/m³Pasadena, 12 March: 7.8 µg/m³Pasadena, 13 March: 17.2 µg/m³Pasadena, 14 March: 26.9 µg/m³, 2.7× its usual 10.0Pasadena, 15 March: 28.5 µg/m³Pasadena, 16 March: 5.5 µg/m³Pasadena, 17 March: 8.1 µg/m³Pasadena, 18 March: 6.1 µg/m³Ciudad Benito JuárezCiudad Benito Juárez, 11 March: 28.9 µg/m³Ciudad Benito Juárez, 12 March: 26.5 µg/m³Ciudad Benito Juárez, 13 March: 26.3 µg/m³Ciudad Benito Juárez, 14 March: 29.0 µg/m³Ciudad Benito Juárez, 15 March: 38.8 µg/m³, 2.1× its usual 18.2Ciudad Benito Juárez, 16 March: 27.3 µg/m³Ciudad Benito Juárez, 17 March: 27.9 µg/m³Ciudad Benito Juárez, 18 March: 21.1 µg/m³MissionMission, 11 March: 4.8 µg/m³Mission, 12 March: 10.2 µg/m³Mission, 13 March: 22.9 µg/m³Mission, 14 March: 23.6 µg/m³Mission, 15 March: 29.3 µg/m³, 2.6× its usual 11.4Mission, 16 March: 21.4 µg/m³Mission, 17 March: 11.7 µg/m³Mission, 18 March: 9.6 µg/m³11 Mar12131415161718
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
LubbockTexas, United States1 57.014 March4.411×
ChanuteKansas, United States1 77.614 March8.49.2×
DentonTexas, United States1 63.014 March7.09.0×
LeawoodKansas, United States1 44.214 March5.38.3×
OdessaTexas, United States1 52.914 March6.87.8×
OlatheKansas, United States1 57.514 March7.57.7×
Fort WorthTexas, United States1 60.114 March8.07.5×
KearneyMissouri, United States1 38.814 March5.27.5×
LibertyMissouri, United States1 38.814 March5.27.5×
EdmondOklahoma, United States1 56.214 March7.67.4×
Kansas CityKansas, United States1 52.914 March8.26.5×
LawtonOklahoma, United States1 44.414 March6.86.5×
Kansas CityMissouri, United States1 42.614 March6.76.4×
TulsaOklahoma, United States1 60.914 March9.86.2×
Ponca CityOklahoma, United States1 51.314 March8.66.0×
GlenpoolOklahoma, United States1 54.214 March9.25.9×
JenksOklahoma, United States1 54.214 March9.25.9×
McAlesterOklahoma, United States1 46.514 March7.95.9×
Fort SmithArkansas, United States1 45.314 March8.15.6×
MooreOklahoma, United States1 45.914 March8.45.5×
River OaksTexas, United States1 39.114 March7.55.2×
SaginawTexas, United States1 39.114 March7.55.2×
KaufmanTexas, United States1 36.614 March7.15.2×
MiamiOklahoma, United States1 46.114 March9.15.1×
TopekaKansas, United States1 40.614 March8.05.1×
DerbyKansas, United States1 39.114 March7.65.1×
HaysvilleKansas, United States1 39.114 March7.65.1×
Oklahoma CityOklahoma, United States1 43.014 March8.65.0×
Saint JosephMissouri, United States1 32.114 March7.34.4×
Heroica MatamorosTamaulipas, Mexico2 41.614 March10.24.1×
SpringdaleArkansas, United States1 34.114 March8.93.8×
WichitaKansas, United States1 33.514 March9.03.7×
Port IsabelTexas, United States2 48.715 March14.33.4×
Mission BendTexas, United States1 28.014 March9.43.0×
Lacy-LakeviewTexas, United States1 27.714 March9.13.0×
ConroeTexas, United States1 29.914 March10.22.9×
Corpus ChristiTexas, United States1 30.114 March11.12.7×
PasadenaTexas, United States1 26.914 March10.02.7×
MissionTexas, United States1 29.315 March11.42.6×
HoustonTexas, United States1 27.914 March11.52.4×
Cadereyta JiménezNuevo León, Mexico2 35.614 March15.72.3×
Ciudad Benito JuárezNuevo León, Mexico1 38.815 March18.22.1×

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 Mexico

Number 33 of 163 episodes in the United States and Mexico since our records began, by cities reached.

Bars: cities reached; colour: the level of the episode's highest daily reading. All 163.

Use this page

SmogRank, United States and Mexico, March 2025: 42 cities with PM2.5 at twice their usual or more, 14 to 15 March 2025, smogrank.com/episodes/2025-03-united-states-and-mexico (accessed 5 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.