Eight-Hour Ozone High Value Days for 2016
as of September 25
The table below lists the daily maximum eight-hour ozone concentrations measured which meet or exceed 71 parts per billion in 2016 in each community where the TCEQ measures ozone. This information is updated hourly. Concentrations are color-highlighted based on the EPA-defined Air Quality Index colors. (See Interpreting the AQI.) Times shown are in 24-hour format and are Local Standard Time. Our convention is that the time reflects the beginning of the eight-hour average. All ozone measurements are in parts per billion.Use the selection boxes below to customize this report. You may select a different year, a different sorting order, or a different report format. Click on the Generate Report button once you have made your selections.
| 2016 Sorted by Maximum Value | |||||||
|---|---|---|---|---|---|---|---|
| Location | Region | CAMS | AQS | Date | Time | Value | POC |
| Ft. Worth Northwest C13/AH302 | 4 | 13 | 48_439_1002 | June 7 2016 | 12:00 | 95 | 2 |
| Arlington Municipal Airport C61 | 4 | 61 | 48_439_3011 | June 7 2016 | 11:00 | 95 | 1 |
| Houston Aldine C8/AF108/X150 | 12 | 8 | 48_201_0024 | August 3 2016 | 11:00 | 89 | 2 |
| West Houston C554 | 12 | 554 | 48_201_0554 | May 6 2016 | 11:00 | 89 | 1 N |
| Parker County C76 | 4 | 76 | 48_367_0081 | June 7 2016 | 15:00 | 88 | 1 |
| Bunker Hill Village C562 | 12 | 562 | 48_201_0562 | May 6 2016 | 11:00 | 86 | 1 N |
| West Houston C554 | 12 | 554 | 48_201_0554 | July 21 2016 | 09:00 | 85 | 1 N |
| Cleburne Airport C77/C682 | 4 | 77 | 48_251_0003 | June 7 2016 | 11:00 | 85 | 1 |
| Keller C17 | 4 | 17 | 48_439_2003 | June 7 2016 | 12:00 | 85 | 2 |
| Chamizal C41/AH126 | 6 | 41 | 48_141_0044 | June 23 2016 | 10:00 | 84 | 1 |
| Galveston 99th St. C1034/A320/X183 | 12 | 1034 | 48_167_1034 | April 23 2016 | 10:00 | 84 | 1 |
| Houston Bayland Park C53/A146 | 12 | 53 | 48_201_0055 | May 6 2016 | 10:00 | 84 | 1 |
| Houston Westhollow C410 | 12 | 410 | 48_201_0066 | May 6 2016 | 10:00 | 84 | 1 |
| HRM-3 Haden Road C603/A114 | 12 | 603 | 48_201_0803 | September 19 2016 | 09:00 | 84 | 1 N |
| Denton Airport South C56/A163/X157 | 4 | 56 | 48_121_0034 | June 8 2016 | 10:00 | 83 | 1 |
| Pilot Point C1032 | 4 | 1032 | 48_121_1032 | June 30 2016 | 11:00 | 83 | 1 |
| Houston Aldine C8/AF108/X150 | 12 | 8 | 48_201_0024 | July 22 2016 | 11:00 | 83 | 2 |
| Houston Bayland Park C53/A146 | 12 | 53 | 48_201_0055 | April 15 2016 | 11:00 | 83 | 1 |
| Grapevine Fairway C70/A301/X182 | 4 | 70 | 48_439_3009 | June 7 2016 | 11:00 | 83 | 1 |
| Dallas Hinton St. C401/C60/AH161 | 4 | 401 | 48_113_0069 | June 7 2016 | 11:00 | 82 | 3 |
| Galveston 99th St. C1034/A320/X183 | 12 | 1034 | 48_167_1034 | May 4 2016 | 12:00 | 82 | 1 |
| Dallas Executive Airport C402 | 4 | 402 | 48_113_0087 | June 7 2016 | 11:00 | 81 | 1 |
| Denton Airport South C56/A163/X157 | 4 | 56 | 48_121_0034 | September 21 2016 | 11:00 | 81 | 1 |
| Chamizal C41/AH126 | 6 | 41 | 48_141_0044 | August 8 2016 | 10:00 | 81 | 1 |
| UH WG Jones Forest C698 | 12 | 698 | 48_339_0698 | May 7 2016 | 10:00 | 81 | 1 N |
| Ascarate Park SE C37/A332/A172/X159 | 6 | 37 | 48_141_0055 | June 23 2016 | 10:00 | 80 | 1 |
| Lang C408 | 12 | 408 | 48_201_0047 | April 23 2016 | 11:00 | 80 | 2 |
| Granbury C73/C681 | 4 | 73 | 48_221_0001 | June 7 2016 | 11:00 | 80 | 1 |
| Cleburne Airport C77/C682 | 4 | 77 | 48_251_0003 | June 6 2016 | 11:00 | 80 | 1 |
| Conroe Relocated C78/A321 | 12 | 78 | 48_339_0078 | May 7 2016 | 11:00 | 80 | 1 |
| Denton Airport South C56/A163/X157 | 4 | 56 | 48_121_0034 | July 1 2016 | 10:00 | 79 | 1 |
| Northwest Harris Co. C26/A110/X154 | 12 | 26 | 48_201_0029 | July 21 2016 | 12:00 | 79 | 2 |
| Houston Westhollow C410 | 12 | 410 | 48_201_0066 | April 15 2016 | 11:00 | 79 | 1 |
| Houston Westhollow C410 | 12 | 410 | 48_201_0066 | April 23 2016 | 10:00 | 79 | 1 |
| Mercer Arboretum C557 | 12 | 557 | 48_201_0557 | July 22 2016 | 11:00 | 79 | 1 N |
| Katy Park C559 | 12 | 559 | 48_201_0559 | May 6 2016 | 12:00 | 79 | 1 N |
| Pilot Point C1032 | 4 | 1032 | 48_121_1032 | June 8 2016 | 10:00 | 78 | 1 |
| El Paso UTEP C12/A125/X151 | 6 | 12 | 48_141_0037 | June 23 2016 | 10:00 | 78 | 2 |
| El Paso UTEP C12/A125/X151 | 6 | 12 | 48_141_0037 | August 8 2016 | 10:00 | 78 | 2 |
| U of H-Sugarland C696 | 12 | 696 | 48_157_0696 | September 3 2016 | 10:00 | 78 | 1 N |
| Northwest Harris Co. C26/A110/X154 | 12 | 26 | 48_201_0029 | April 23 2016 | 11:00 | 78 | 2 |
| Lang C408 | 12 | 408 | 48_201_0047 | May 6 2016 | 11:00 | 78 | 2 |
| Houston Bayland Park C53/A146 | 12 | 53 | 48_201_0055 | April 23 2016 | 10:00 | 78 | 1 |
| Houston Bayland Park C53/A146 | 12 | 53 | 48_201_0055 | May 13 2016 | 10:00 | 78 | 1 |
| Houston Westhollow C410 | 12 | 410 | 48_201_0066 | June 8 2016 | 10:00 | 78 | 1 |
| Cleburne Airport C77/C682 | 4 | 77 | 48_251_0003 | August 31 2016 | 11:00 | 78 | 1 |
| UH WG Jones Forest C698 | 12 | 698 | 48_339_0698 | July 22 2016 | 12:00 | 78 | 1 N |
| Skyline Park C72 | 6 | 72 | 48_141_0058 | June 23 2016 | 10:00 | 77 | 1 |
| U of H-Sugarland C696 | 12 | 696 | 48_157_0696 | September 21 2016 | 10:00 | 77 | 1 N |
| UH WG Jones Forest C698 | 12 | 698 | 48_339_0698 | April 27 2016 | 12:00 | 77 | 1 N |
| Grapevine Fairway C70/A301/X182 | 4 | 70 | 48_439_3009 | June 20 2016 | 11:00 | 77 | 1 |
| Frisco C31/C680 | 4 | 31 | 48_085_0005 | June 30 2016 | 10:00 | 76 | 1 |
| Frisco C31/C680 | 4 | 31 | 48_085_0005 | July 1 2016 | 09:00 | 76 | 1 |
| Denton Airport South C56/A163/X157 | 4 | 56 | 48_121_0034 | June 30 2016 | 11:00 | 76 | 1 |
| Ascarate Park SE C37/A332/A172/X159 | 6 | 37 | 48_141_0055 | August 8 2016 | 10:00 | 76 | 1 |
| UH WG Jones Forest C698 | 12 | 698 | 48_339_0698 | August 4 2016 | 11:00 | 76 | 1 N |
| Grapevine Fairway C70/A301/X182 | 4 | 70 | 48_439_3009 | June 30 2016 | 10:00 | 76 | 1 |
| Denton Airport South C56/A163/X157 | 4 | 56 | 48_121_0034 | June 9 2016 | 09:00 | 75 | 1 |
| Pilot Point C1032 | 4 | 1032 | 48_121_1032 | June 9 2016 | 10:00 | 75 | 1 |
| Pilot Point C1032 | 4 | 1032 | 48_121_1032 | July 1 2016 | 10:00 | 75 | 1 |
| Galveston 99th St. C1034/A320/X183 | 12 | 1034 | 48_167_1034 | June 8 2016 | 12:00 | 75 | 1 |
| Houston Aldine C8/AF108/X150 | 12 | 8 | 48_201_0024 | April 27 2016 | 11:00 | 75 | 2 |
| Houston Texas Avenue C411 | 12 | 411 | 48_201_0075 | May 6 2016 | 10:00 | 75 | 1 |
| Conroe Relocated C78/A321 | 12 | 78 | 48_339_0078 | April 5 2016 | 11:00 | 75 | 1 |
| Conroe Relocated C78/A321 | 12 | 78 | 48_339_0078 | April 27 2016 | 11:00 | 75 | 1 |
| Grapevine Fairway C70/A301/X182 | 4 | 70 | 48_439_3009 | September 21 2016 | 11:00 | 75 | 1 |
| Galveston 99th St. C1034/A320/X183 | 12 | 1034 | 48_167_1034 | April 7 2016 | 11:00 | 74 | 1 |
| Houston Aldine C8/AF108/X150 | 12 | 8 | 48_201_0024 | April 23 2016 | 11:00 | 74 | 2 |
| Lang C408 | 12 | 408 | 48_201_0047 | July 21 2016 | 10:00 | 74 | 2 |
| Houston Croquet C409 | 12 | 409 | 48_201_0051 | September 21 2016 | 10:00 | 74 | 2 |
| UH Moody Tower C695 | 12 | 695 | 48_201_0695 | May 6 2016 | 10:00 | 74 | 1 N |
| SETRPC 40 Sabine Pass C640/C1654 | 10 | 640 | 48_245_0101 | April 4 2016 | 11:00 | 74 | 1 |
| UH WG Jones Forest C698 | 12 | 698 | 48_339_0698 | March 26 2016 | 12:00 | 74 | 1 N |
| UH WG Jones Forest C698 | 12 | 698 | 48_339_0698 | April 5 2016 | 11:00 | 74 | 1 N |
| San Antonio Northwest C23 | 13 | 23 | 48_029_0032 | May 5 2016 | 11:00 | 73 | 2 |
| Frisco C31/C680 | 4 | 31 | 48_085_0005 | August 5 2016 | 11:00 | 73 | 1 |
| Dallas Hinton St. C401/C60/AH161 | 4 | 401 | 48_113_0069 | September 11 2016 | 12:00 | 73 | 3 |
| Denton Airport South C56/A163/X157 | 4 | 56 | 48_121_0034 | June 10 2016 | 10:00 | 73 | 1 |
| Pilot Point C1032 | 4 | 1032 | 48_121_1032 | September 22 2016 | 10:00 | 73 | 1 |
| Houston Aldine C8/AF108/X150 | 12 | 8 | 48_201_0024 | April 3 2016 | 11:00 | 73 | 2 |
| Houston Westhollow C410 | 12 | 410 | 48_201_0066 | May 13 2016 | 10:00 | 73 | 1 |
| SETRPC 40 Sabine Pass C640/C1654 | 10 | 640 | 48_245_0101 | April 7 2016 | 12:00 | 73 | 1 |
| UH WG Jones Forest C698 | 12 | 698 | 48_339_0698 | August 3 2016 | 13:00 | 73 | 1 N |
| Ft. Worth Northwest C13/AH302 | 4 | 13 | 48_439_1002 | July 26 2016 | 10:00 | 73 | 2 |
| Denton Airport South C56/A163/X157 | 4 | 56 | 48_121_0034 | June 20 2016 | 12:00 | 72 | 1 |
| Denton Airport South C56/A163/X157 | 4 | 56 | 48_121_0034 | September 22 2016 | 10:00 | 72 | 1 |
| El Paso UTEP C12/A125/X151 | 6 | 12 | 48_141_0037 | June 6 2016 | 11:00 | 72 | 2 |
| Ascarate Park SE C37/A332/A172/X159 | 6 | 37 | 48_141_0055 | July 16 2016 | 10:00 | 72 | 1 |
| Houston Aldine C8/AF108/X150 | 12 | 8 | 48_201_0024 | July 21 2016 | 10:00 | 72 | 2 |
| Houston Croquet C409 | 12 | 409 | 48_201_0051 | June 8 2016 | 10:00 | 72 | 2 |
| Houston Bayland Park C53/A146 | 12 | 53 | 48_201_0055 | September 21 2016 | 09:00 | 72 | 1 |
| Sheldon C551 | 12 | 551 | 48_201_0551 | April 3 2016 | 10:00 | 72 | 1 N |
| Holly Road C660 | 14 | 660 | 48_355_0660 | September 2 2016 | 11:00 | 72 | 1 N |
| Eagle Mountain Lake C75 | 4 | 75 | 48_439_0075 | June 7 2016 | 12:00 | 72 | 1 |
| Keller C17 | 4 | 17 | 48_439_2003 | June 29 2016 | 11:00 | 72 | 2 |
| Keller C17 | 4 | 17 | 48_439_2003 | July 26 2016 | 10:00 | 72 | 2 |
| Grapevine Fairway C70/A301/X182 | 4 | 70 | 48_439_3009 | September 20 2016 | 10:00 | 72 | 1 |
| San Antonio Northwest C23 | 13 | 23 | 48_029_0032 | May 6 2016 | 10:00 | 71 | 2 |
| Dallas Hinton St. C401/C60/AH161 | 4 | 401 | 48_113_0069 | June 20 2016 | 11:00 | 71 | 3 |
| Pilot Point C1032 | 4 | 1032 | 48_121_1032 | August 5 2016 | 12:00 | 71 | 1 |
| El Paso UTEP C12/A125/X151 | 6 | 12 | 48_141_0037 | July 16 2016 | 11:00 | 71 | 2 |
| Galveston 99th St. C1034/A320/X183 | 12 | 1034 | 48_167_1034 | April 14 2016 | 11:00 | 71 | 1 |
| Galveston 99th St. C1034/A320/X183 | 12 | 1034 | 48_167_1034 | May 7 2016 | 17:00 | 71 | 1 |
| Houston Aldine C8/AF108/X150 | 12 | 8 | 48_201_0024 | May 7 2016 | 09:00 | 71 | 2 |
| Crosby Library C553 | 12 | 553 | 48_201_0553 | April 3 2016 | 13:00 | 71 | 1 N |
| West Houston C554 | 12 | 554 | 48_201_0554 | June 8 2016 | 10:00 | 71 | 1 N |
| Bunker Hill Village C562 | 12 | 562 | 48_201_0562 | April 23 2016 | 11:00 | 71 | 1 N |
| Houston East C1/G316 | 12 | 1 | 48_201_1034 | May 6 2016 | 11:00 | 71 | 2 |
| Conroe Relocated C78/A321 | 12 | 78 | 48_339_0078 | August 4 2016 | 11:00 | 71 | 1 |
| Tyler Airport Relocated C82 | 5 | 82 | 48_423_0007 | June 30 2016 | 11:00 | 71 | 1 |
| Grapevine Fairway C70/A301/X182 | 4 | 70 | 48_439_3009 | July 1 2016 | 10:00 | 71 | 1 |
| 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
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 beginning 1/1/2013, 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.