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AutoGC Data by Day by Site (all parameters)

Use this form to retrieve hourly data collected at TCEQ Automated Gas Chromatograph (AutoGC) monitoring stations. 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.

This web page provides the most current hourly averaged data available. Our convention for time-tagging data is the beginning of each hour. For example, values shown for the noon hour are based on measurements taken from noon to 1:00 p.m. The noon average will not be calculated until after 1:00 p.m. The noon average will then be available on our external server from 1:15 p.m. to 1:30 p.m. This results in an apparent one-hour time lag in the data. We also present our data in Local Standard Time for each measuring site. For most of Texas this is Central Standard Time. During Daylight Savings, this introduces another apparent one-hour time lag in the data.

Select a date: Use the buttons below to select which date you want reported.
    Today (July 14, 2024)
    Yesterday (July 13, 2024)
    Specify a date
Select a Site: View hourly averages for any or all compounds measured at any AutoGC site. Select the site you are interested in from the list below. The compounds you select below will be shown at the selected monitoring site (if that site measures the parameter you select). Please note that not all parameters are measured at all sites.
      Measured in: ppb-Volume   ppb-Carbon
      Air Monitoring Comparison Value Highlights:  Odor   Short-Term Vegetation   Short-Term Health   (if defined for a particular parameter)
      Report Format:  Tabular (webified)   Comma-delimited

    Once you have made your selections above, click on the Generate Report button.

    Advanced Options

    You may use the checkboxes below to control which parameters will be in the report. If you have cookies enabled on your browser, these selections will be "remembered" from session to session.

      Ethane [P] *2-Methyl-1-Pentene [P] n-Propylbenzene [BP] *
      Ethylene [P] *1-Hexene [P] m-Ethyltoluene [BP]
      Propane [P] *n-Hexane [BP] *p-Ethyltoluene [BP]
      Propylene [P] *t-2-Hexene [BP] 1,3,5-Trimethylbenzene [BP] *
      Isobutane [P] *c-2-Hexene [BP] o-ethyltoluene [BP]
      n-Butane [P] *Methylcyclopentane [BP] *1,2,4-Trimethylbenzene [BP] *
      Acetylene [P] *2,4-Dimethylpentane [BP] *n-Decane [BP] *
      t-2-Butene [P] *Benzene [BP] *1,2,3-Trimethylbenzene [BP] *
      1-Butene [P] *Cyclohexane [BP] *m-Diethylbenzene [BP]
      Isobutene [P] 2-Methylhexane [BP] *p-Diethylbenzene [BP]
      c-2-Butene [P] *2,3-Dimethylpentane [BP] *n-Undecane [BP]
      Cyclopentane [P] *3-Methylhexane [BP] *a-Pinene [BP]
      Isopentane [P] *2,2,4-Trimethylpentane [BP] *b-Pinene [BP]
      n-Pentane [P] *n-Heptane [BP] *Cyclopentene [P]
      1,3-Butadiene [P] *Methylcyclohexane [BP] *3-Methyl-1-Butene [P]
      3-Methyl-1-Butene+Cyclopentene [P] 2,3,4-Trimethylpentane [BP] *Wind Speed
      t-2-Pentene [P] *Toluene [BP] *Resultant Wind Speed
      2-Methyl-2-Butene [P] 2-Methylheptane [BP] *Resultant Wind Direction
      1-Pentene [P] *3-Methylheptane [BP] *
      c-2-Pentene [P] *n-Octane [BP] *
      2,2-Dimethylbutane [P] *Ethyl Benzene [BP] *
      2,3-Dimethylbutane [P] p-Xylene + m-Xylene [BP] *
      2-Methylpentane [P] Styrene [BP] *
      3-Methylpentane [P] o-Xylene [BP] *
      Isoprene [P] *n-Nonane [BP] *
      4-Methyl-1-Pentene [P] Isopropyl Benzene - Cumene [BP] *
      * - Target Compounds effective April 1998

    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.