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We are setting up a weather station for the Tridell, Utah area that will be premiering online soon, and we are stumped on one item. I understand the differences between Absolute and Relative Air Pressure, but one thing about relative air pressure I read in the weather station setup kind of through me off a little. I hope that this will make since to you. It says that:
"...It can be programmed to represent your local surroundings. Since the relative air pressure is also the one value given by various newspapers, TV and radio broadcasting stations in their daily weather forecasts for their respective locations, users can set the relative air pressure of the weather station to this value to represent readings your their area...Relative air pressure setting from 27.10 inHg - 31.90 inHg (default 29.98 inHg)."
Does this statement mean that I need to somehow find out what the "normal/standard" relative air pressure is for the Tridell area is so I can give it a reference point? I thought that the absolute pressure gave relative pressure its reference point from sea level?
Thanks,
Matt W.
Tridell, Utah
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Basically you need a pressure reading that has been standardized to sea level for your area. You can use another weather sensor nearby. The link on the right will take you to the Utah Mesonet and you can totally check weather sensors around you.
You have to standardize your pressure or you'll get really whacked out readings that say something like 24.5 inches of mercury. That is a station pressure. It has to be standardized so we can forecast and make maps of our weather. If we always had lower pressure readings at higher elevations, we'd have a big old Low contstantly sitting over the Rockies, that really doesn't help anyone out.
There's a special equation that factors this in called the "hypsometric equation". It relates pressure and heights at different levels. You can do a little reading up on it if you like but it will be much simpler to just calibrate your barometer with one close by. Best of luck.
Answered by KSL Meteorologist Dina Freedman.
