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Four Highest 24-Hour PM-2.5 Concentrations in 2024
as of May 20, 2024

Use this form to retrieve the four highest 24-hour PM-2.5 concentration averages from data collected at TCEQ monitoring sites beginning January 1, 1998 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 24-hour PM-2.5 concentrations measured in 2024 in each community where the TCEQ measures PM-2.5. Concentrations that are rated Moderate or higher are color-highlighted based on the EPA-defined Air Quality Index colors. (See Interpreting the AQI.). All PM-2.5 measurements are in micrograms per cubic meter (local conditions). Sample times correspond to the beginning of the 24-hour average (midnight to midnight).

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
AreaMonitoring SitePOCHighestSecond HighestThird HighestFourth Highest
Amarillo Texas A&M C320202/27/202450.605/01/202411.704/25/202411.702/29/20249.8
Lubbock 12th Street C1028102/27/202430.503/24/202419.402/28/202413.905/01/202412.7
Dallas-Fort Worth
Ft. Worth Northwest C13/AH302 305/08/202427.304/01/202418.304/27/202418.005/06/202417.6
Denton Airport South C56/A163/X157104/01/202418.705/08/202417.302/27/202415.603/24/202413.9
Kaufman C71/A304/X071105/08/202427.904/18/202417.103/06/202415.604/01/202415.4
Haws Athletic Center C310201/02/202423.804/04/202421.805/08/202420.204/27/202419.1
Convention Center C312305/08/202427.804/17/202419.804/01/202419.203/06/202417.4
Dallas Hinton St. C401/C60/AH161 405/08/202428.504/01/202422.204/27/202421.504/17/202419.6
Corsicana Airport C1051105/08/202437.505/09/202423.605/07/202419.304/18/202419.1
Ft Worth California Parkway North C1053205/08/202422.304/01/202419.304/27/202418.701/02/202417.8
Ft Worth California Parkway North C1053305/08/202424.204/27/202422.004/01/202421.803/20/202421.1
Dallas Bexar Street C10961 N05/08/202429.801/11/202422.402/09/202422.001/12/202419.1
Karnack C85/AFHP303204/05/2024188.104/04/2024129.104/06/202480.205/08/202426.8
Texarkana New Boston C1031205/08/202431.305/16/202420.105/15/202419.705/07/202418.7
El Paso-Juarez
Ascarate Park SE C37/A332/A172/X1593 N03/24/202499.604/18/202492.804/15/202491.204/06/202482.6
Chamizal C41/AH126 603/24/202448.001/11/202436.803/31/202436.602/28/202433.0
Socorro Hueco C49/F3123 N03/24/202446.604/15/202444.801/11/202435.704/06/202428.6
BRAVO Big Bend C67/C316/C656/C691102/28/202424.701/11/202420.204/30/202419.805/01/202419.3
Odessa Gonzales C1014 103/24/202428.704/01/202425.502/28/202419.104/30/202416.6
Waco Mazanec C10373 N05/08/202437.005/09/202430.004/01/202422.302/27/202420.8
Temple Georgia C1045105/08/202437.905/09/202427.704/27/202419.904/01/202419.5
Bryan Finfeather Road105/08/202435.905/09/202426.505/07/202422.304/01/202418.3
Beaumont-Port Arthur
Hamshire C64/C654204/29/202437.205/09/202434.005/13/202416.905/08/202416.5
Port Arthur Memorial School C303/C689405/09/202438.005/15/202424.705/08/202423.001/01/202421.4
Port Arthur Memorial School C303/C689605/09/202434.905/15/202425.305/08/202421.005/13/202418.3
SETRPC Port Arthur C6281 N04/01/202418.304/09/202416.203/23/202415.203/14/202414.7
SETRPC Mauriceville 42 C642/C311/C665105/09/202436.405/13/202421.305/08/202415.501/01/202415.5
Austin North Hills Drive C3/A322105/08/202443.105/09/202431.804/01/202426.504/27/202423.1
Austin Webberville Road AF171405/08/202451.805/09/202435.604/01/202434.201/01/202432.7
Dripping Springs School C6141 N05/19/202418.205/18/202411.405/17/20244.5No Data
Austin North Interstate 35 C1068205/08/202444.305/09/202429.804/01/202426.501/01/202425.8
Jarrell FM 487 C10941 N05/08/202440.905/09/202431.304/01/202424.904/27/202422.8
Lockhart C16041 N05/19/202418.905/18/202413.905/17/20247.1No Data
CAPCOG Taylor Murphy Park C16291 N05/19/202415.405/18/202411.605/17/20246.0No Data
CAPCOG San Marcos Staples Road C16751 N05/19/202419.905/18/202412.1No DataNo Data
Houston East C1/G316101/01/202472.605/09/202440.102/19/202418.403/02/202416.4
Houston Aldine C8/AF108/X150 405/09/202436.005/08/202422.705/18/202418.505/07/202418.4
Hou.DeerPrk2 C35/235/1001/AFH139FP239605/09/202441.301/01/202423.005/08/202421.905/18/202419.6
Seabrook Friendship Park C45105/09/202431.605/08/202417.903/14/202414.704/01/202414.3
Houston Bayland Park C53/A146 101/01/202468.805/09/202439.405/08/202425.205/07/202419.6
Conroe Relocated C78/A321105/09/202439.701/01/202436.005/08/202427.505/07/202427.3
Clinton C403/C304/AH113 3 N01/01/202452.905/09/202438.305/08/202426.102/27/202421.5
Houston North Wayside C405/C1033101/01/2024103.105/09/202444.704/09/202434.705/08/202427.3
Houston Westhollow C410/C3003101/01/202453.205/09/202443.205/08/202427.905/07/202422.9
Galveston 99th St. C1034/A320/X183205/09/202430.005/07/202419.705/13/202415.805/08/202415.2
Houston North Loop C1052201/01/202494.005/09/202444.005/08/202426.805/07/202422.4
Oyster Creek C1607 1 N05/09/202432.805/10/202419.505/08/202418.504/28/202416.0
Liberty Sam Houston Library C16261 N05/09/202429.405/08/202418.404/01/202415.003/11/202414.3
San Antonio
San Antonio Northwest C23205/08/202438.805/09/202434.204/27/202427.705/19/202425.9
Calaveras Lake C59205/08/202438.805/09/202433.004/01/202425.804/27/202423.8
Heritage Middle School C6223 N05/08/202445.305/09/202436.204/01/202428.704/27/202428.1
Old Highway 90 C677/A3193 N01/01/2024123.805/08/202432.805/09/202428.504/01/202424.7
San Antonio IH 35 C1069205/08/202440.805/09/202432.704/01/202427.504/27/202425.2
San Antonio Bulverde Parkway205/08/202447.305/09/202440.304/01/202436.104/27/202433.5
New Braunfels Oak Run Parkway1 N05/08/202436.205/09/202427.204/01/202421.304/27/202421.1
Von Ormy Highway 16 C1090105/08/202441.605/09/202435.804/01/202432.105/19/202429.3
San Antonio Red Hill Lane C10911 N05/09/202447.805/12/202430.305/15/202428.501/01/202427.9
Corpus Christi-Victoria
Corpus Christi Huisache C98/A155305/09/202445.805/08/202440.605/16/202436.405/10/202431.5
Corpus Christi Huisache C98/A155405/09/202445.505/08/202440.705/16/202434.105/10/202432.4
National Seashore C314105/09/202443.705/10/202436.005/16/202433.305/08/202432.8
Dona Park C635/AF199/F2991 N01/01/202412.901/11/202412.001/12/20249.701/02/20249.4
Dona Park C635/AF199/F299305/09/202454.905/08/202446.405/16/202439.405/10/202438.2
Lower Rio Grande Valley
Mission C43/AP143505/10/202455.705/16/202451.405/09/202445.505/08/202443.5
Isla Blanca Park C323/C667105/10/202483.405/17/202482.705/09/202478.205/16/202470.6
Edinburg East Freddy Gonzalez Dr C1046205/10/202449.305/16/202446.605/08/202439.505/09/202438.7
Brownsville East 6th Street C1098105/10/202444.605/08/202443.005/09/202442.105/16/202441.9
World Trade Bridge C313104/27/202437.505/02/202431.905/19/202430.605/08/202429.5
Eagle Pass C319/C655104/27/202433.105/16/202430.605/09/202427.805/08/202427.8
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 24hr PM-2.5
in µg/m³ LC
0 - 50 0 - 9.0
51 - 100 9.1 - 35.4
101 - 150 35.5 - 55.4
151 - 200 55.5 - 125.4
201 - 300 125.5 - 225.4
301 - 400 225.5 - 350.4
401 - 500 350.5 - 500.4
500+ Not Defined
  • The AQI for PM-2.5 is based on a 24-hour average sampled from midnight to 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.