Quote:
Originally Posted by MetroMPG
[B]Conditions:
Grenadier Island Past 24 Hour Conditions
... Pressure (kPa) ... Vis (km) ... Wind Chill
... 101.8 ...
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Just wanted to mention that if your baro reading was from a weather station or radio, then the baro reading is 'corrected' for elevation back to sea level, and may need to be corrected for your current elevation above sea level.
For example, our TV station always reports our current barometric conditions as if we are located at sea level, even though our elevation in Wisconsin is actually about 1000 feet.
So for our location, the TV station would report a typical 29.9 inches Hg, but our 'actual' measured barometric pressure is really 28.9 inches Hg. That also means that our actual air density is lower than reported by the TV station.
Now when performing coast-downs, one should properly calculate the 'true' barometric pressure based on:
1) the TV station reading
2) your actual elevation above sea level
3) subtract one inch of Hg for each 1000 feet above sea level
4) from the TV station baro reading
5) now you have the actual baro reading at your location
Hope this helps, Jim.
Now back to our normally scheduled program....
