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Hourly Data by Pollutant (all sites)

Use this form to retrieve hourly data collected at Virginia DEQ monitoring stations. For air monitoring stations, we continuously sample the atmosphere (one sample per second), and every five minutes an average of all the one-second samples collected is calculated for each parameter monitored. Hourly averages are then calculated from these five-minute averages. Hourly averages are then calculated from these samples. 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. 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 (March 26, 2017)
Yesterday (March 25, 2017)
Specify a date

Select a Parameter:

View hourly averages for any pollutant or meteorological condition measured by Virginia DEQ. Select the parameter you are interested in from the list below. Data will be shown from all Virginia DEQ monitoring sites that measure the parameter you select. Please note that not all parameters are measured at all sites.

Select a time format:

Choose to have the report generated in either an AM/PM format or in a 24-hour format. This time format only affects the labeling in the table header and not the report contents. The report is always generated in Local Standard Time (LST) for each reporting station.

AM/PM Format
24 Hour Format

Select a Region:

You may choose to have the report limited to only sites measuring your selected parameter located in a specific region. Select All Active Regions to report on all sites where your selected parameter is monitored.

Once you have made your selections above, click on the Generate Report button. You may use the Reset to Defaults button to clear selections you have made.

Select Highlighting Options:

For Sulfur Dioxide, Nitrogen Dioxide, Ozone, and PM-2.5 you may choose to have the background cell color highlighted based on the values reported. The highlight colors correspond to air quality ratings.

For PM-2.5, there is a national 24-hour standard. The daily average (if you have selected this statistic and it is available for the specific report) will be highlighted based on this national standard.

 OzoneSulfur DioxideNitrogen DioxidePM-2.5
Unhealthy For Sensitive Groups
Very Unhealthy

PLEASE NOTE: This data has not been verified by the Virginia DEQ 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 Virginia DEQ 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.