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Today is 10.11.06 the reported pressure is 30.16 in Salt Lake City at 3 pm. I have a gage which reads 25.8. I am thinking the reported pressure has been normalized for sea level (altitude). What is the formula for doing this. If I am wrong please let me know and guide to the knowledge of the truth.
Mike G
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Unless you want to plug away at equations forever you probably don't want the total equation. The equation to work on this is called the hypsometric equation, this relates elevation and pressure. Or some version of this equation will help you. All pressures are reported as sea level, if they weren't, we'd have constant low pressure over Utah!
You can also use the rule of thumb that the atmospheric pressure will decrease 1 Kpa per 100 meters. Since we don't live in Canada you need to convert those units over to inches of mercury and feet. 1 Kilo Pascal is .2953 inches of mercury and 100 meters is 328.08 feet. So the pressure will decrease .2953 inches of mercury for every 328.08 of higher elevation.
Knowing your elevation, you should be able to figure out your sea level pressure. Nope, it's not fun!
Your equation would end up looking like this.
Sea Level Pressure=Observed Station Pressure +{(.2953 inches hg/328.08 ft)*height above sea level in feet}
Let me know how that works out for you. If your pressure was 25.8 inches of mercury and you lived in Salt Lake at the airport where the elevation is 4266 feet you actually do come up with a reasonable answer on this so check it out.
Best of luck with this one!
Answered by KSL Meteorologist Dina Freedman.
