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Daily Maximum Eight-Hour Ozone Averages for March 2023

The table below lists the peak daily maximum eight-hour ozone concentrations measured in March 2023 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.) All ozone measurements are in parts per billion.

Use the selection boxes below to customize this report. You may select a different month, a different year, a different report format, and whether or not to include time on the report. Click on the Generate Report button once you have made your selections.

Month:Year:Report Format: Include time:
Include time
Highlight with AQI colors
AreaMonitoring SitePOCMarch 2023POCMonitoring Site
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Dallas-Fort Worth
Ft. Worth Northwest C13/AH302 218NVNV485445201518323140424051364445474437403639495942NA2Ft. Worth Northwest C13/AH302
Keller C1722132374750442115183226384039503441414441353732NV455244NA2Keller C17
Frisco C31/C6801213539565456211721343138424651384344464237403634475447NA1Frisco C31/C680
Denton Airport South C56/A163/X1571253241535654241716NV3340414751374546474438413736475247NA1Denton Airport South C56/A163/X157
Arlington Municipal Airport C611173239515141211418312736394349354343444035373036486141NA1Arlington Municipal Airport C61
Dallas North No.2 C63/C6791NV3337524947NV1620342836384248NV3942454135383427485943NA1Dallas North No.2 C63/C679
Rockwall Heath C69118333647454218NANV3133364142453643444541363233NVNANANANA1Rockwall Heath C69
Grapevine Fairway C70/A301/X1821243238515048171618312937414145354343443831373334455644NA1Grapevine Fairway C70/A301/X182
Kaufman C71/A304/X0711243741545547262126323635434648394546484441363737515945NA1Kaufman C71/A304/X071
Granbury C73/C681118NVNV505139231720373040413753364544474534393346475435NA1Granbury C73/C681
Eagle Mountain Lake C75 1243544525449251617353541414051374544474538403643495547NA1Eagle Mountain Lake C75
Parker County C761263539494944291718373542414053384645464534373145485147NA1Parker County C76
Cleburne Airport C77/C6821233540515238281621352939414053354343464437393342475741NA1Cleburne Airport C77/C682
Dallas Hinton St. C401/C60/AH161 31028NV51484316NV22312537414346364044453833343123456044NA3Dallas Hinton St. C401/C60/AH161
Dallas Executive Airport C4021NANANANANANANANANANANANANANANANANANANANANV363236496643NA1Dallas Executive Airport C402
Greenville C1006/A1981223538515651282026373638444649424545495047404130575846NA1Greenville C1006/A198
Pilot Point C10321283039545455221820313538404449374345454136423726465145NA1Pilot Point C1032
Italy C1044/A32312933NV555045261628NV3737434453NV4545474336363439495745NA1Italy C1044/A323
Corsicana Airport C10511283440525043261930253231414051364244444238353532475546NA1Corsicana Airport C1051
AreaMonitoring SitePOCMarch 2023POCMonitoring Site
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Tyler-Longview-Marshall
Longview C19/A127/C6442293037445335342829162325424143384346464642393727525259NA2Longview C19/A127/C644
Tyler Airport Relocated C821283743505948303132233232434748414647474944385030535750NA1Tyler Airport Relocated C82
Karnack C85/AFHP3031292834455337332529232426NVNANANANANANANANANANANANANANANA1Karnack C85/AFHP303
AreaMonitoring SitePOCMarch 2023POCMonitoring Site
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El Paso-Juarez
Ascarate Park SE C37/A332/A172/X1591354134374333331735313338363535344043413226274342414442NA1Ascarate Park SE C37/A332/A172/X159
Chamizal C41/AH126 1454943435140423645413845454643394242444032345152495250NA1Chamizal C41/AH126
Socorro Hueco C49/F3121434541464944383943403643444743374345453933344649495048NA1Socorro Hueco C49/F312
Skyline Park C7215657545552454342453736464443443937424751NV35NV52515052NA1Skyline Park C72
Ivanhoe C414/F5141383936404339NV3441363239414539363941393427304242434445NA1Ivanhoe C414/F514
Ojo De Agua C1021/FG121/FG22114446414446424039444036424244413943464439NVNANANANANANANA1Ojo De Agua C1021/FG121/FG221
AreaMonitoring SitePOCMarch 2023POCMonitoring Site
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Waco
Waco Mazanec C1037133384362544930173531393644385537464749NV35353142505948NA1Waco Mazanec C1037
Temple Georgia C10451363643645347NV2334333636463653374644494330373044495048NA1Temple Georgia C1045
Killeen Skylark Field C10471393743595545362538353239473654364646494533393249504749NA1Killeen Skylark Field C1047
AreaMonitoring SitePOCMarch 2023POCMonitoring Site
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Beaumont-Port Arthur
Beaumont-Downtown C2/A112/C2002 2242642515230212628302331383647433238434542382926552028NA2Beaumont-Downtown C2/A112/C2002
West Orange C9/A1412212642505431203032272530393951453038444845412726542029NA2West Orange C9/A141
Port Arthur West C28/A128/A2281232441464830202523302432373845403136414541382627572026NA1Port Arthur West C28/A128/A228
Hamshire C64/C65412429445254NVNANANANANANANV4348433438444743392727542029NA1Hamshire C64/C654
SETRPC Port Arthur C6281 N28294751553925293134283644475148374247474742322861NVNANA1SETRPC Port Arthur C628
SETRPC 40 Sabine Pass C640/C16541252641425337212427262428363948453639465046413028552226NA1SETRPC 40 Sabine Pass C640/C1654
SETRPC Mauriceville 42 C642/C311/C6651 N27304652583224393528273040445347354047484743322854NVNANA1SETRPC Mauriceville 42 C642/C311/C665
SETRPC 43 Jefferson Co Airport C6431222442524927202625302230383745383337444539362525591826NA1SETRPC 43 Jefferson Co Airport C643
Nederland 17th Street C103512527435653252329NV32253339NVNV433439454844402928632130NA1Nederland 17th Street C1035
AreaMonitoring SitePOCMarch 2023POCMonitoring Site
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Austin
Austin North Hills Drive C3/A322241475372585030343835413941425035NV42484327342746504046NA2Austin North Hills Drive C3/A322
Audubon C38137384562514124NV34353537464250364541504521342948484048NA1Audubon C38
Dripping Springs School C6141 N344445624941252827262931433940334137433322292444463442NA1Dripping Springs School C614
CAPCOG Lake Georgetown C6901 N343639575142302532293033423848354541494429352843474344NA1CAPCOG Lake Georgetown C690
Lockhart C16041 N343746594938213030303037454847324342494128322535483535NA1Lockhart C1604
St. Edwards University C16051 N283742544437212627263032403844324240454026302441463541NA1St. Edwards University C1605
CAPCOG Bastrop CAMS16121 N303844564837222927273032424347353936444128302433483439NA1CAPCOG Bastrop CAMS1612
CAPCOG Elgin C16131 N294145574936232927313033444248334237483926292342543943NA1CAPCOG Elgin C1613
CAPCOG East Austin C16191 N364250665545273234NV3837474652394544514633393049574450NA1CAPCOG East Austin C1619
CAPCOG Round Rock Brushy Creek W C16201 N34374063534728302933373968NVNVNVNANANANANANV2843494245NA1CAPCOG Round Rock Brushy Creek W C1620
CAPCOG San Marcos Staples Road C16751 N364551615239233235313232454748324043494429342744514441NA1CAPCOG San Marcos Staples Road C1675
AreaMonitoring SitePOCMarch 2023POCMonitoring Site
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Houston-Galveston-Brazoria
Houston East C1/G3162273240676026253633312734324351413035444441372920652112NA2Houston East C1/G316
Houston Aldine C8/AF108/X150 2233039645531223029242526393746313233423835352921551722NA2Houston Aldine C8/AF108/X150
Channelview C15/AH115 3233344585427242625322632373946363537464430362818602322NA3Channelview C15/AH115
Northwest Harris Co. C26/A110/X1542263442637039323732242925414355373838494744403629551336NA2Northwest Harris Co. C26/A110/X154
Hou.DeerPrk2 C35/235/1001/AFH139FP2391253345565633243230412635404549423538464641372921682319NA1Hou.DeerPrk2 C35/235/1001/AFH139FP239
Seabrook Friendship Park C451223245NANANV1823263722343846NV373235444637332519571914NA1Seabrook Friendship Park C45
Houston Bayland Park C53/A146 12635456559403034303627284244NV41373948NV42383327652426NA1Houston Bayland Park C53/A146
Conroe Relocated C78/A3211313544606242364640253225434257373941474741434024521732NA1Conroe Relocated C78/A321
Manvel Croix Park C841243747595433273030372531434649393737474739NV2921632219NA1Manvel Croix Park C84
Clinton C403/C304/AH113 32330416259262228253323313843493334394844353527NV67217NA3Clinton C403/C304/AH113
Houston North Wayside C405/C103312126356253271929NANV2225343642313234413833312214551520NA1Houston North Wayside C405/C1033
Houston Monroe C40612132425149312327273623293239453729324142NV332617581811NA1Houston Monroe C406
Lang C4082253543656138252929292625394149353434444138353024581921NA2Lang C408
Houston Croquet C4092253341595434273129342626364350373232414539353023592121NA2Houston Croquet C409
Houston Westhollow C410/C30031172835554930202420231920373742273131404033272320491723NA1Houston Westhollow C410/C3003
Park Place C41612434436057362632NV39253137425038NVNANA454036NV19672114NA1Park Place C416
Houston Harvard Street C4171273443686340283532352829394552383537474640393224642222NA1Houston Harvard Street C417
Sheldon C5511 N212942615122192521282328373945313638454234342615551618NA1Sheldon C551
Baytown Wetlands Center C5521 N182339484826212425352130374344333237434437312413551519NA1Baytown Wetlands Center C552
Crosby Library C5531 N222942595228253532262427384048373338434641362815531820NA1Crosby Library C553
West Houston C5541 N243443676137273229262625414552353737454438343023531933NA1West Houston C554
La Porte Sylvan Beach C5561 N202942425230162121422033374548373337444736332116441612NA1La Porte Sylvan Beach C556
Mercer Arboretum C5571 N263142676239283734232824424153323639474437393320541227NA1Mercer Arboretum C557
Tom Bass C5581 N233444595532262928382329384550383537464740362819641914NA1Tom Bass C558
Katy Park C5591 N243542605535242926252628444649343737454537332824481935NA1Katy Park C559
Atascocita C5601 N23263762NVNANV3226202323373645323133384132322716471317NA1Atascocita C560
Meyer Park C5611 N25314167673627343024262540425334363844423935311951928NA1Meyer Park C561
Bunker Hill Village C5621 N23304062573426312729242541NVNANANANANANANANANANANANANANA1Bunker Hill Village C562
Huffman Wolf Road C5631 N253042575338314136232827433949393337424441393218482123NA1Huffman Wolf Road C563
Texas City 34th St. C620 1 NNV415663644832333453304852555952464754NVNANANANANANANANA1Texas City 34th St. C620
UH Moody Tower C6951 N243444605735253231382630384250383438464440373020682217NA1UH Moody Tower C695
UH WG Jones Forest C6981 N3137476765423442392632NA444358364042514638413831561433NA1UH WG Jones Forest C698
Lynchburg Ferry C1015/A165 1253041505428212525272729374347383033394633372418522111NA1Lynchburg Ferry C1015/A165
Lake Jackson C1016 1273851606132263228322637525051473935505249413425662531NA1Lake Jackson C1016
Baytown Garth C10171303649606439354041393238454853473943495147443624642730NA1Baytown Garth C1017
Galveston 99th St. C1034/A320/X1831263553566246252630332335154652494242465451443230642627NA1Galveston 99th St. C1034/A320/X183
Oyster Creek C1607 1 N28364657583927312831263749495146363650524842332669NVNANA1Oyster Creek C1607
Liberty Sam Houston Library C16261 N242943535633233531NV252738394839NV3743454041292115NVNANA1Liberty Sam Houston Library C1626
AreaMonitoring SitePOCMarch 2023POCMonitoring Site
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San Antonio
San Antonio Northwest C2324048506158412935353335384649NV404239474231362946514845NA2San Antonio Northwest C23
Camp Bullis C58 138485063604328363734363747504838444048NV30373049514945NA1Camp Bullis C58
Calaveras Lake C591435063645641293335293241464948384343474431372949545142NA1Calaveras Lake C59
Elm Creek Elementary C5011 N364448575136263231293337414344363836424030342746534643NA1Elm Creek Elementary C501
Fair Oaks Ranch C5021 N314242545036243130292832414341333735393524312540413837NA1Fair Oaks Ranch C502
Bulverde Elementary C5031 N333739524534212328252627363837293329353121272239414237NA1Bulverde Elementary C503
New Braunfels Airport C5041 N354550605139232730272830364242303635423726292339434036NA1New Braunfels Airport C504
AACOG City of Garden Ridge C505 1 N394547594940242025212628313631243228253722322445475238NA1AACOG City of Garden Ridge C505
Seguin Outdoor Learning Center C5061 N333844554736223031262829394242323634434027322638464037NA1Seguin Outdoor Learning Center C506
Heritage Middle School C6221 N374656575037253031302936424544354038444128NV2746524638NA1Heritage Middle School C622
CPS Pecan Valley C6781 N283638433729182224212122323534213030353214231828363429NA1CPS Pecan Valley C678
Government Canyon C16101 N294445564833243029292833424341313733373522272139423536NA1Government Canyon C1610
AreaMonitoring SitePOCMarch 2023POCMonitoring Site
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Corpus Christi-Victoria
Corpus Christi West C42274057565237232726242646455147404141424440342535642424NA2Corpus Christi West C4
Corpus Christi Tuloso C211NV3958585232222726272649454647394143434436352535622521NA1Corpus Christi Tuloso C21
Victoria C871254052565133232926322434313740313540414235332536492428NA1Victoria C87
AreaMonitoring SitePOCMarch 2023POCMonitoring Site
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Lower Rio Grande Valley
Harlingen Teege C10231283751565332263230323139394543374546484237362637513127NA1Harlingen Teege C1023
AreaMonitoring SitePOCMarch 2023POCMonitoring Site
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Laredo
Laredo College C441 N454550585442363738313848424141484244444443423451575234NA1Laredo College C44
POC (Parameter Occurrence Code): a code used to correctly separate data from multiple instruments at one site.
NV - There are not enough valid eight-hour averages for this day (there must be eighteen valid eight-hour averages).
NA - Data not available.
 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.