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Four Highest Eight-Hour Ozone Concentrations in 2024
as of April 18

Use this form to retrieve the four highest eight-hour ozone concentration averages from data collected at TCEQ monitoring sites beginning December 14, 2005 through today. Although this is our most current data, it is not considered official until it has been certified by our technical staff. This information is updated hourly. All times shown are in Local Standard Time.

The table below lists the four highest daily maximum eight-hour ozone concentrations measured in 2024 in each community where the TCEQ measures ozone. Concentrations that are rated Moderate or higher are color-highlighted based on the EPA-defined Air Quality Index colors. (See Interpreting the AQI.) The fourth-highest average is in bold black (unless it is highlighted). All ozone measurements are in parts per billion. Times are shown in 24-hour format and correspond to the beginning of the eight hour average.

Use the selection boxes below to customize this report. You may select a different year or a different report format. If you want to cut and paste data from this web page into another application, such as a spreadsheet, select the comma-delimited format. Click on the Generate Report button once you have made your selections.

YearReport Format
Highlight with AQI colors
Area Monitoring Site POC Highest Second Highest Third Highest Fourth Highest
Date Time Value Date Time Value Date Time Value Date Time Value
Dallas-Fort Worth
Ft. Worth Northwest C13/AH302 204/05/202411005404/13/202410005104/12/202411005004/04/2024100050
Keller C17204/05/202411005904/16/202411005504/04/202411005504/13/2024110054
Frisco C31/C680104/05/202411006704/16/202411005704/13/202411005604/12/2024120055
Denton Airport South C56/A163/X157104/05/202412006204/12/202412005604/16/202410005404/13/2024100054
Arlington Municipal Airport C61103/11/202411004803/05/202411004702/26/202411004703/02/2024110046
Dallas North No.2 C63/C679104/05/202411006204/04/202412005504/13/202410005404/07/2024110054
Rockwall Heath C69104/05/202410005904/04/202411005604/07/202410005503/28/2024110053
Grapevine Fairway C70/A301/X182104/16/202411005404/05/202411005404/13/202410005204/04/2024110052
Kaufman C71/A304/X071104/05/202410006204/04/202412005804/07/202410005603/28/2024110056
Granbury C73/C681104/12/202413006204/16/202410005804/13/202411005804/05/2024100058
Eagle Mountain Lake C75 104/05/202411005704/13/202412005604/16/202410005504/12/2024110055
Parker County C76104/16/202410005704/12/202413005504/05/202411005403/06/2024120053
Cleburne Airport C77/C682104/12/202411005504/05/202411005503/28/202413005404/13/2024110053
Dallas Hinton St. C401/C60/AH161 304/05/202411006204/04/202411006003/28/202412005804/13/2024110057
Dallas Executive Airport C402104/05/202411006104/04/202411005904/13/202411005703/28/2024110057
Greenville C1006/A198104/05/202410006304/07/202411006003/29/202411005603/10/2024100056
Pilot Point C1032104/05/202410006904/16/202411006004/04/202410006004/13/2024110058
Italy C1044/A323103/28/202411005504/04/202411005403/05/202412005404/13/2024100051
Corsicana Airport C1051104/05/202410006104/04/202411005703/28/202411005601/31/2024120056
Tyler-Longview-Marshall
Longview C19/A127/C644202/01/202411006303/29/202412006104/05/202411006004/07/2024100058
Tyler Airport Relocated C82103/29/202413006404/05/202411006304/13/202412006204/07/2024100058
Karnack C85/AFHP303104/04/202411006203/29/202410005704/13/202410005504/05/2024100055
El Paso-Juarez
Ascarate Park SE C37/A332/A172/X159104/15/202417005704/06/202414005604/07/202411005204/17/2024100051
Chamizal C41/AH126 104/06/202414006604/17/202409006504/16/202411006504/15/2024130065
Socorro Hueco C49/F312104/16/202410006104/07/202411005804/06/202414005804/17/2024100057
Skyline Park C72104/17/202411006604/16/202411006304/15/202416006304/11/2024100061
Ivanhoe C414/F514104/17/202410005504/16/202411005404/15/202419005104/07/2024110050
Ojo De Agua C1021/FG121/FG221104/17/202410005904/15/202415005904/16/202411005704/11/2024100052
Waco
Waco Mazanec C1037104/05/202411006004/04/202411005803/28/202411005704/12/2024110055
Temple Georgia C1045104/12/202411005704/04/202411005704/05/202410005504/13/2024100052
Killeen Skylark Field C1047104/12/202412006504/05/202411006004/04/202411006003/28/2024120060
Beaumont-Port Arthur
Beaumont-Downtown C2/A112/C2002 204/04/202411005904/05/202410005704/12/202410005503/29/2024100054
West Orange C9/A141204/05/202410005704/04/202411005704/13/202412005404/12/2024110054
Port Arthur West C28/A128/A228104/04/202411005304/13/202414005204/12/202410005104/05/2024100050
Hamshire C64/C654104/04/202413006704/12/202410006004/13/202409005503/28/2024110055
SETRPC Port Arthur C6281 N04/04/202413006704/05/202410006103/23/202412006004/13/2024160059
SETRPC 40 Sabine Pass C640/C1654104/04/202413006604/13/202410006003/23/202412005704/12/2024100056
SETRPC Mauriceville 42 C642/C311/C6651 N04/05/202410007004/04/202410006004/13/202411005904/06/2024100055
SETRPC 43 Jefferson Co Airport C643104/04/202412005704/12/202410005503/28/202411005504/05/2024100052
Nederland 17th Street C1035104/12/202411005904/04/202411005804/13/202411005604/05/2024090055
Austin
Austin North Hills Drive C3/A322204/04/202411006504/12/202411006204/07/202411005703/28/2024110057
Audubon C38104/12/202411005904/04/202412005703/28/202412005604/05/2024110053
Dripping Springs School C6141 N04/04/202411006904/12/202411006603/28/202412006404/05/2024110062
CAPCOG Lake Georgetown C6901 N04/12/202412005904/04/202412005503/28/202412005404/05/2024100051
Lockhart C16041 N04/04/202411006304/12/202410006204/11/202410005804/07/2024100056
CAPCOG Bastrop CAMS16121 N04/04/202411006004/12/202412005503/11/202409005202/24/2024100052
CAPCOG Elgin C16131 N03/28/202411005704/04/202411005603/29/202411005304/12/2024140051
CAPCOG East Austin C16191 N04/12/202411005804/04/202411005803/28/202412005202/25/2024100051
CAPCOG Taylor Murphy Park C16291 N04/04/202411006304/12/202411005903/28/202411005404/05/2024100052
CAPCOG Lake Kyle Park C16301 N04/04/202411005904/05/202414005503/28/202411005304/07/2024090050
CAPCOG San Marcos Staples Road C16751 N04/04/202411005904/12/202410005604/13/202410005103/28/2024110051
Houston-Galveston-Brazoria
Houston East C1/G316204/12/202410006204/04/202410006203/28/202410006104/05/2024100056
Houston Aldine C8/AF108/X150 204/12/202410007304/04/202411006104/05/202410005904/13/2024100055
Channelview C15/AH115 304/05/202410005604/04/202409005602/19/202409005502/24/2024120054
Northwest Harris Co. C26/A110/X154204/12/202411006403/28/202411005604/04/202410005504/05/2024100053
Hou.DeerPrk2 C35/235/1001/AFH139FP239104/04/202411006304/12/202411005803/23/202412005804/13/2024100055
Seabrook Friendship Park C45104/04/202411006102/24/202410005904/03/202412005404/02/2024100054
Houston Bayland Park C53/A146 103/23/202411006704/12/202410006204/04/202410006203/28/2024120059
Conroe Relocated C78/A321104/05/202410007304/13/202410007104/12/202412007103/06/2024110070
Manvel Croix Park C84104/04/202410006103/23/202411006004/11/202410005403/28/2024110054
Clinton C403/C304/AH113 303/28/202411005504/12/202411005404/04/202410005303/23/2024120051
Houston North Wayside C405/C1033104/12/202411006503/28/202411006304/04/202410005504/05/2024100052
Houston Monroe C406103/23/202411005704/04/202410005503/28/202411005004/12/2024100048
Lang C408204/12/202411006103/23/202412005904/04/202410005704/13/2024090054
Houston Croquet C409203/23/202412006504/04/202410005604/12/202410005503/28/2024110054
Houston Westhollow C410/C3003103/23/202412006204/12/202410005904/04/202410005903/28/2024100059
Park Place C416104/04/202410006103/23/202411005904/12/202410005704/05/2024090053
Houston Harvard Street C417104/04/202411005903/28/202412005904/12/202411005803/23/2024120056
Sheldon C5511 N04/04/202409005902/19/202410005904/12/202410005703/28/2024100056
Baytown Wetlands Center C5521 N04/04/202409005804/12/202410005504/13/202411005304/05/2024090052
Crosby Library C5531 N04/04/202410006403/28/202410006304/12/202410006204/05/2024100060
West Houston C5541 N04/12/202410006604/04/202409006203/28/202411006103/23/2024100058
La Porte Sylvan Beach C5561 N02/24/202410006104/04/202411005804/13/202411005104/05/2024100050
Mercer Arboretum C5571 N04/12/202410007403/28/202410006604/05/202409006004/04/2024100058
Tom Bass C5581 N03/23/202411007004/04/202409005903/28/202410005902/01/2024120059
Katy Park C5591 N04/12/202410006004/04/202409005703/28/202411005604/05/2024100052
Atascocita C5601 N03/28/202410006704/05/202409005904/04/202410005803/29/2024080054
Meyer Park C5611 N04/12/202410006804/04/202410006003/28/202411006004/05/2024090059
Bunker Hill Village C5621 N04/12/202410005903/23/202411005904/04/202410005703/28/2024100056
Huffman Wolf Road C5631 N02/19/202410006504/05/202409006304/04/202411006003/28/2024100060
HRM-3 Haden Road C603/A114 1 N04/12/202411006604/04/202410006604/05/202411006003/28/2024100059
Wallisville Road C617 1 N04/04/202411007004/05/202410006404/12/202410006204/13/2024090061
Texas City 34th St. C620 1 N04/04/202411007604/12/202410006704/11/202410006504/13/2024130063
UH Moody Tower C6951 N04/04/202411006103/28/202412006004/12/202411005803/23/2024120058
UH WG Jones Forest C6981 N04/12/202412007303/28/202411006704/05/202411006404/04/2024120063
Lynchburg Ferry C1015/A165 104/12/202411006304/05/202411005904/13/202412005703/28/2024100054
Lake Jackson C1016 104/04/202411006403/28/202410005804/12/202410005602/24/2024100054
Baytown Garth C1017104/04/202411006204/05/202410005804/12/202411005604/13/2024090055
Galveston 99th St. C1034/A320/X183104/04/202412007104/12/202410006403/23/202416006304/11/2024100062
Oyster Creek C1607 1 N04/04/202411006704/12/202409005902/01/202410005804/11/2024100056
Liberty Sam Houston Library C16261 N04/04/202412006804/05/202411006504/12/202412005603/28/2024120055
San Antonio
San Antonio Northwest C23204/12/202410005904/13/202409005604/04/202411005503/28/2024110055
Camp Bullis C58 104/12/202411006204/13/202410005804/04/202411005703/28/2024110057
Calaveras Lake C59104/12/202410005904/04/202411005903/28/202411005704/13/2024100056
Elm Creek Elementary C5011 N04/12/202410005904/04/202410005704/13/202409005503/28/2024100055
Fair Oaks Ranch C5021 N04/12/202411005904/13/202410005604/04/202411005303/28/2024100053
Bulverde Elementary C5031 N04/12/202410005204/13/202410004904/04/202410004903/28/2024110049
New Braunfels Airport C5041 N04/04/202411006504/12/202410006103/28/202411005704/13/2024090056
AACOG City of Garden Ridge C505 1 N04/04/202410006204/12/202411006003/28/202411005704/13/2024100055
Seguin Outdoor Learning Center C5061 N04/04/202411005004/12/202410004802/24/202412004703/28/2024110046
Heritage Middle School C6221 N04/12/202411006404/13/202410005903/28/202411005904/03/2024110057
CPS Pecan Valley C6781 N02/24/202411004902/25/202410004802/23/202411004704/12/2024110045
Government Canyon C16101 N04/12/202411005804/04/202410005703/28/202411005404/13/2024100053
Corpus Christi-Victoria
Corpus Christi West C4202/23/202411005704/13/202407005604/12/202406005603/22/2024120056
Corpus Christi Tuloso C21104/12/202409005703/23/202413005604/13/202408005503/22/2024120055
Victoria C87104/12/202411006403/28/202411005704/03/202411005603/23/2024130056
Lower Rio Grande Valley
Mission C43/AP143102/24/202410005302/23/202410005104/11/202410004903/02/2024120049
Harlingen Teege C1023102/24/202411006104/12/202409005602/23/202409005604/13/2024080055
Laredo
Laredo College C441 N04/11/202410006403/27/202411006102/24/202411006004/12/2024120059
POC (Parameter Occurrence Code): a code used to correctly separate data from multiple instruments at one site.
 N - Data from this instrument does not meet EPA quality assurance criteria and cannot be used for regulatory purposes.

Interpreting the AQI

Air Quality Index

Each NAAQS pollutant has a separate AQI scale, with an AQI rating of 100 corresponding to the concentration of the Federal Standard for that pollutant. Additional information about the AQI and how it can be used is available from the EPA's AirNow web site.

Place your mouse pointer over the scale displayed above to view information about the Air Quality Index, and each of the rating levels.

The actual index calculation is different for each parameter measured and is specified by the EPA. The following table shows the various breakpoints used in calculating the AQI.

AQI Breakpoint Definitions
AQI Range 1hr Ozone
in ppm		 8hr Ozone
in ppm
0 - 50 Not Defined 0 - 0.054
51 - 100 Not Defined 0.055 - 0.070
101 - 150 0.125 - 0.164 0.071 - 0.085
151 - 200 0.165 - 0.204 0.086 - 0.105
201 - 300 0.205 - 0.404 0.106 - 0.200
301 - 400 0.405 - 0.504 Not Defined
401 - 500 Not Defined Not Defined
500+ Not Defined Not Defined
  • The AQI for ozone is based on either the peak eight-hour running average since midnight OR the peak one-hour measurement since midnight.

PLEASE NOTE:  This data has not been verified by the TCEQ and may change. This is the most current data, but it is not official until it has been certified by our technical staff. Data is collected from TCEQ ambient monitoring sites and may include data collected by other outside agencies. This data is updated hourly. All times shown are in local standard time unless otherwise indicated.

Following EPA reporting guidelines, negative values may be displayed in our hourly criteria air quality data, down to the negative of the EPA listed Method Detection Limit (MDL) for the particular instrument that made the measurements. The reported concentrations can be negative due to zero drift in the electronic instrument output, data logger channel, or calibration adjustments to the data. Prior to 1/1/2013, slightly negative values were automatically set to zero.