Please note that the  barometric pressure displayed on our website is the actual pressure. Most weather reports indicate the pressure at sea level, which is about 3" of mercury higher than the pressure at the elevation of the SDSM&T campus, which is about 3400' above sea level. It is hard to do an accurate correction to sea level with the system we have; however, for an explanation of how to do so, please visit one of the following websites: http://taja.dynip.com/baropres.htm;  http://www.crh.noaa.gov/unr/science/mslp/index.php or the Exploratorium museum web site from San Francisco: http://www.exploratorium.edu/weather/barometer.html . In addition, some laboratory exercises in chemistry and mechanical engineering require students to know the actual pressure.