Skip to main content

Daily Maximum Eight-Hour Ozone Averages for April 2020

The table below lists the peak daily maximum eight-hour ozone concentrations measured in April 2020 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 SitePOCApril 2020
Dallas-Fort Worth
Ft. Worth Northwest C13/AH302 24235221020313543NA
Keller C1724237271124333442NA
Frisco C31/C68014641331129364749NA
Midlothian OFW C52/A13715144401834NV3241NA
Denton Airport South C56/A163/X1571NV37251226353944NA
Arlington Municipal Airport C6114336311128293444NA
Dallas North No.2 C63/C67914539311027324048NA
Rockwall Heath C6914140311028323449NA
Grapevine Fairway C70/A301/X18214437271125324144NA
Kaufman C71/A304/X07114141331030283340NA
Granbury C73/C68114435211224273343NA
Eagle Mountain Lake C75 14638241224373947NA
Parker County C7614736211424333547NA
Cleburne Airport C77/C6821463325930272939NA
Dallas Hinton St. C401/C60/AH161 34234281028283444NA
Dallas Executive Airport C40214740331128293343NA
Greenville C1006/A198142402392332NVNANA
Pilot Point C103214739271230384846NA
Italy C1044/A3231423934725303238NA
Corsicana Airport C10511444138925353336NA
AreaMonitoring SitePOCApril 2020
Longview C19/A127/C6442444634632392833NA
Tyler Airport Relocated C821434228733363434NA
Karnack C85/AFHP3031504941626353238NA
AreaMonitoring SitePOCApril 2020
El Paso-Juarez
El Paso UTEP C12/A125/X151/G125246474548494443NVNA
Ascarate Park SE C37/A332/A172/X159148464346504141NVNA
Chamizal C41/AH126 151534851534846NVNA
Socorro Hueco C49/F312147494948504444NVNA
Skyline Park C72152504949494643NVNA
Ivanhoe C414/F514148494848504443NVNA
AreaMonitoring SitePOCApril 2020
Waco Mazanec C10371493730830323536NA
Temple Georgia C104514934251031353940NA
Killeen Skylark Field C104715135271130363641NA
AreaMonitoring SitePOCApril 2020
Beaumont-Port Arthur
Beaumont-Downtown C2/A112/C2002 25354463346362636NA
West Orange C9/A14125253504352NV2531NA
Port Arthur West C28/A128/A2281494736313725611NA
Hamshire C64/C65415251482950362433NA
SETRPC 40 Sabine Pass C640/C1654150545047483823NVNA
SETRPC 43 Jefferson Co Airport C64315255494149392330NA
Nederland High School C1035 14752463147362228NA
AreaMonitoring SitePOCApril 2020
Audubon C3815231171021323537NA
AreaMonitoring SitePOCApril 2020
Houston East C1/G3162514543938273039NA
Houston Aldine C8/AF108/X150 2574849734353138NA
Channelview C15/AH115 3NV44421339283036NA
Northwest Harris Co. C26/A110/X1542614850731402933NA
Hou.DeerPrk2 C35/235/1001/AFH139FP23915349471947372732NA
Seabrook Friendship Park C451NV46452446322327NA
Houston Bayland Park C53/A146 1594848644362834NA
Conroe Relocated C78/A3211564745726402934NA
Manvel Croix Park C8415145431245332426NA
Clinton C403/C304/AH113 3514443941302226NA
Houston North Wayside C4051464039629252330NA
Houston Monroe C406150NANV1541332528NA
Lang C4082544440534282834NA
Houston Croquet C4092504342740332427NA
Houston Westhollow C41015646468423729NVNA
Park Place C41615146441040352731NA
Lynchburg Ferry C1015/A165 15045431842322128NA
Lake Jackson C1016 152NVNANANANV20NVNA
Baytown Garth C101715048471944382841NA
Galveston 99th St. C1034/A320/X18315251534653462322NA
AreaMonitoring SitePOCApril 2020
San Antonio
San Antonio Northwest C23254NV222339333142NA
Camp Bullis C58 15831111527NVNVNVNA
Calaveras Lake C5915433271536442842NA
AreaMonitoring SitePOCApril 2020
Corpus Christi-Victoria
Corpus Christi West C424542373046361925NA
Corpus Christi Tuloso C2114744352745372234NA
Victoria C8714844341247342435NA
AreaMonitoring SitePOCApril 2020
Lower Rio Grande Valley
Mission C43/AP14315233252433262436NA
Harlingen Teege C102314333263036252328NA
AreaMonitoring SitePOCApril 2020
Laredo Vidaurri C44/AFGP144/P24415434341931262534NA
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.

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.