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Four Highest Eight-Hour Ozone Concentrations in 2017
as of November 22

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 2017 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 205/30/201710007908/04/201711007705/13/201712007409/13/2017110073
Keller C17209/13/201711008108/04/201711007906/23/201712007505/06/2017120075
Frisco C31/C680109/02/201710007708/10/201712007305/06/201712007309/18/2017110072
Midlothian OFW C52/A137106/07/201710007709/01/201711007005/13/201711006705/06/2017090067
Denton Airport South C56/A163/X157106/08/201711008010/19/201710007305/31/201710007305/07/2017100073
Arlington Municipal Airport C61109/01/201711007909/13/201711007808/03/201711007506/07/2017100071
Dallas North No.2 C63/C679109/13/201711008109/01/201712008105/06/201711008008/04/2017100077
Rockwall Heath C69105/06/201711007209/01/201711006909/13/201710006708/04/2017110067
Grapevine Fairway C70/A301/X182108/04/201710008306/08/201711007809/13/201711007306/23/2017120073
Kaufman C71/A304/X071109/13/201711007405/06/201710006505/07/201711006409/14/2017100062
Granbury C73/C681107/31/201713008109/30/201711007206/21/201710007108/04/2017110066
Eagle Mountain Lake C75 108/04/201711007605/30/201711007506/08/201711007110/19/2017100070
Parker County C76105/30/201711007406/20/201715006609/09/201711006508/04/2017130065
Cleburne Airport C77/C682106/07/201710008407/31/201712008108/03/201711007607/29/2017150075
Dallas Hinton St. C401/C60/AH161 309/01/201712008205/06/201711008008/04/201711007809/13/2017120075
Dallas Executive Airport C402106/07/201709006705/06/201710006408/04/201712006308/01/2017100063
Greenville C1006/A198105/06/201711007007/28/201711006805/07/201709006705/01/2017110066
Pilot Point C1032106/08/201711007609/14/201711007309/02/201711006805/15/2017100068
Italy C1044/A323109/12/201710007105/06/201709006709/11/201711006606/07/2017110066
Corsicana Airport C1051109/12/201710007305/06/201710007005/07/201710006709/14/2017100065
Tyler-Longview-Marshall
Longview C19/A127/C644209/14/201710006305/25/201712006204/08/201715006204/07/2017100062
Tyler Airport Relocated C82102/23/201714006709/13/201709006406/08/201709006305/06/2017120063
Karnack C85/AFHP303109/14/201710007009/02/201710006705/25/201711006305/07/2017100063
El Paso-Juarez
El Paso UTEP C12/A125/X151206/27/201710007506/06/201710007508/17/201711007407/28/2017110074
Ascarate Park SE C37/A332/A172/X159109/12/201710007806/02/201711006906/27/201710006808/24/2017110067
Chamizal C41/AH126 109/12/201710008206/27/201710007406/04/201710007408/24/2017110072
Socorro Hueco C49/F312106/27/201711006709/12/201710006506/04/201711006307/12/2017110062
Skyline Park C72106/07/201712008009/12/201710007909/07/201709007506/27/2017110075
BRAVO Big Bend C67/C316/C656/C6913 N06/05/201709006604/30/201713006505/11/201712006404/21/2017170063
Ivanhoe C414106/27/201712007509/12/201711006706/15/201710006306/04/2017110063
Waco
Waco Mazanec C1037105/06/201710007409/13/201710007109/12/201710006909/11/2017120069
Temple Georgia C1045109/13/201710008005/06/201710007506/07/201712007205/07/2017110072
Killeen Skylark Field C1047104/07/201711007109/13/201710006905/07/201711006905/06/2017110068
Beaumont-Port Arthur
Beaumont-Downtown C2/A112/C2002 209/13/201710007405/14/201710007306/09/201710006805/07/2017090067
West Orange C9/A141209/13/201709007205/06/201710006205/07/201709006105/02/2017110061
Port Arthur West C28/A128/A228109/13/201709007905/06/201711006605/02/201709006606/09/2017130064
Hamshire C64/C654109/13/201710007805/02/201709006304/24/201712006304/07/2017110063
SETRPC Port Arthur C6281 N05/06/201710006804/24/201711006805/07/201708006705/02/2017080066
SETRPC 40 Sabine Pass C640/C1654109/02/201708007209/13/201709007005/02/201709006905/07/2017080067
SETRPC Mauriceville 42 C642/C311/C6651 N09/13/201710006905/07/201710006904/07/201712006905/02/2017110067
SETRPC 43 Jefferson Co Airport C643105/06/201711006504/24/201710006506/09/201711006405/14/2017100064
Nederland High School C1035 109/13/201710008005/14/201711006705/06/201711006606/09/2017120065
Austin
Austin Northwest C3/A322209/01/201710007106/08/201711007105/06/201710007108/01/2017090070
Audubon C38106/08/201710007305/07/201710006809/13/201710006705/06/2017110067
Fayette County C6012 N05/07/201711006905/06/201710006906/08/201711006709/12/2017110064
Dripping Springs School C6141 N08/01/201711007206/08/201710006805/07/201710006705/06/2017110067
CAPCOG McKinney Roughs C6841 N06/09/201710006206/08/201712006006/07/201710005908/01/2017090057
CAPCOG Lake Georgetown C6901 N06/08/201711007509/13/201710007305/06/201711007305/07/2017100070
Gorzycki Middle School C16031 N06/08/201711006208/01/201710006006/07/201711006009/01/2017110059
Lockhart C16041 N09/12/201709007406/07/201710007405/07/201710007009/01/2017100067
St. Edwards University C16051 N06/07/201710006609/01/201710006408/01/201710006206/08/2017110061
CAPCOG San Marcos Staples Road C16751 N06/07/201711006905/07/201709006704/07/201711006606/08/2017100063
CAPCOG Hutto College Street C66021 N05/06/201710006806/07/201710006706/08/201711006605/01/2017100065
Houston-Galveston-Brazoria
Houston East C1/G316205/06/201710008110/12/201710007310/01/201710007304/07/2017110070
Houston Aldine C8/AF108/X150 210/18/201710008005/14/201710007605/06/201711007610/01/2017100074
Channelview C15/AH115 305/06/201712007804/07/201711006810/12/201710006509/13/2017100065
Northwest Harris Co. C26/A110/X154210/13/201711008010/18/201711007806/09/201711007609/04/2017110074
Hou.DeerPrk2 C35/235/1001/AFH139FP239105/06/201710008109/12/201712007609/02/201709007404/07/2017100066
Seabrook Friendship Park C45109/12/201711008908/04/201710007805/06/201711007305/07/2017090067
Houston Bayland Park C53/A146 109/01/201711009510/18/201710007710/12/201711007505/06/2017110074
Conroe Relocated C78/A321109/14/201711008204/07/201711008104/24/201712008005/15/2017100079
Manvel Croix Park C84106/08/201710008705/06/201711008009/30/201710007810/18/2017100077
Clinton C403/C304/AH113 309/03/201710007809/01/201709007805/06/201711007809/02/2017110077
Houston North Wayside C405105/06/201711007605/14/201710007110/12/201710006910/18/2017100068
Houston Monroe C406105/06/201710007009/12/201712006606/08/201709006109/13/2017090059
Lang C408210/12/201711007710/01/201710007509/01/201709007110/18/2017100070
Houston Croquet C409206/08/201710007405/06/201711007410/18/201710006910/12/2017110067
Houston Westhollow C410110/18/201711007710/12/201711007406/08/201710007205/06/2017110071
Park Place C416109/01/201709007705/06/201710007310/12/201710007209/02/2017100072
Sheldon C5511 N05/06/201710005104/07/201710004704/24/201710004605/07/2017080044
Baytown Wetlands Center C5521 N05/06/201710006704/24/201710005809/12/201712005505/07/2017090053
Crosby Library C5531 N05/06/201711008404/24/201710008309/13/201710007309/14/2017090069
West Houston C5541 N05/06/201710006905/07/201710006705/02/201710006404/24/2017110064
La Porte Sylvan Beach C5561 N09/12/201712007909/02/201709006209/13/201709006010/08/2017100058
Mercer Arboretum C5571 N05/14/201711005205/07/201710005205/02/201710005006/09/2017100049
Tom Bass C5581 N05/06/201711006709/01/201711006405/23/201711006109/08/2017110059
Katy Park C5591 N10/18/201711006505/06/201711006209/01/201710006010/06/2017110059
Atascocita C5601 N09/14/201710007610/18/201710007309/13/201711007210/01/2017100064
Meyer Park C5611 N06/09/201711005905/14/201711005910/18/201711005305/07/2017090052
Bunker Hill Village C5621 N01/03/201710003401/08/201710003301/07/201709003101/02/2017090031
Huffman Wolf Road C5631 N02/22/201712006203/03/201712006102/26/201711005702/24/2017100056
Clear Brook High School C5701 N09/12/201711007705/06/201711007409/05/201710007106/08/2017090070
Clear Creek High School C5711 N09/12/201711008205/06/201711006605/12/201710006508/04/2017100062
HRM-3 Haden Road C603/A114 1 N05/06/201710008104/07/201710007110/01/201710007009/02/2017090070
Wallisville Road C617 1 N05/06/201710008204/07/201710007504/24/201710007409/13/2017100070
Danciger C618 1 N07/31/201711007105/06/201709006709/30/201710006506/07/2017100064
Texas City 34th St. C620 1 N09/12/201711008708/04/201710007605/06/201711007305/12/2017100070
UH Moody Tower C6951 N05/06/201711008109/01/201709008010/12/201710007809/02/2017110074
U of H-Sugarland C6961 N09/08/201711008206/08/201711008210/18/201711007605/06/2017110074
UH Coastal Center C6971 N09/12/201711008309/01/201712006805/12/201711006805/06/2017110067
UH WG Jones Forest C6981 N09/14/201710008505/07/201710008304/24/201711008004/07/2017120079
UH West Liberty C6991 N04/07/201711007804/24/201711007509/13/201710007105/06/2017110068
Lynchburg Ferry C1015/A165 110/18/201710005310/19/201713005010/26/201710004610/12/2017110046
Lake Jackson C1016 105/06/201710006805/13/201711006707/31/201711006506/08/2017110065
Baytown Garth C1017105/06/201710008404/07/201711007804/24/201710007509/13/2017100073
Galveston 99th St. C1034/A320/X183109/12/201711008305/12/201711007605/06/201713007406/08/2017110073
Oyster Creek C1607 1 N05/23/201712006705/06/201709006709/30/201710006606/08/2017110066
San Antonio
San Antonio Northwest C23206/08/201711008008/01/201710007505/07/201710007408/04/2017110073
Camp Bullis C58 106/08/201711008909/13/201711007508/04/201711007208/01/2017100072
Calaveras Lake C59109/12/201711006806/08/201710006805/07/201710006706/07/2017100065
Elm Creek Elementary C5011 N05/13/201712007708/01/201710007005/07/201710006909/30/2017110068
Fair Oaks Ranch C5021 N06/08/201711007509/13/201711007205/07/201710007005/14/2017110067
Bulverde Elementary C5031 N06/08/201711008709/13/201710007405/07/201711006705/06/2017100067
New Braunfels Airport C5041 N04/07/201710006706/08/201710006605/07/201710006606/07/2017110063
City of Garden Ridge C5051 N06/08/201711008105/07/201711006909/13/201710006605/06/2017100066
Seguin Outdoor Learning Center C5061 N05/07/201710006806/08/201711006306/07/201711006202/23/2017110062
Heritage Middle School C6221 N06/08/201711007706/07/201710007005/07/201710007005/13/2017110067
CPS Pecan Valley C6781 N06/08/201711006709/13/201710006108/04/201711006106/07/2017110061
Government Canyon C16101 N09/13/201710006809/01/201711006609/08/201711006309/14/2017110060
Corpus Christi-Victoria
Corpus Christi West C4209/12/201711006402/22/201710006402/25/201715006105/13/2017110060
Corpus Christi Tuloso C21108/01/201709006509/12/201711006405/06/201711006305/13/2017110061
Victoria C87109/12/201711006805/12/201711006506/09/201708006305/06/2017100063
Inez C6091 N09/12/201710006705/12/201711006305/06/201710006310/01/2017100061
Holly Road C6601 N02/22/201711006805/24/201712006702/25/201713006608/01/2017090063
Violet C6641 N10/18/201709006805/13/201710006308/01/201709005906/08/2017090057
Ingleside C6851 N05/06/201716006505/07/201701006106/09/201710006005/13/2017120060
Lower Rio Grande Valley
Mission C43/AP143106/08/201710006405/13/201711005805/01/201711005706/07/2017120055
Brownsville C80/AGP180109/12/201711006005/06/201710006005/01/201711006005/04/2017120058
Harlingen Teege C1023105/06/201709006605/01/201710006509/12/201711006106/08/2017100059
Laredo
Laredo Vidaurri C44/AFGP144/P244109/12/201710005906/22/201711005706/07/201710005609/08/2017100053
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.