Mean sea-level pressure is the force per unit area (pressure) exerted by the atmosphere as a consequence of gravitational attraction exerted upon the "column" of air lying directly above a specific point that has been corrected to a standard reference level (in this case the average sea level). This is the pressure normally shown on televised weather forecasts and newpapers and removes the local effects of altitude on the pressure reading. These values are expressed in millibars. The millibar is a metric unit of pressure commonly used in aviation and meteorology. One millibar is equal to 100 Newtons/meter2 (100 pascals).
Use the controls below to select a different date or parameter. Click on the Generate Report button once you have made your selections.Click on the Plot Data button once the tabular report has been generated to open a separate window containing data plots.
PLEASE NOTE: This data has not been verified by the IDEM 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 IDEM 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.