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Calculating Density Alttitude of Air knoing temp/baro/humidity?

  1. Jan 23, 2009 #1
    I'm trying to figure out the Density Altitude of Air
    Known data
    Temp 70*F
    Barometric Pressure 30inHg
    Humidity 35%

    do I need more data or can I calculet it from this?
  2. jcsd
  3. Jan 23, 2009 #2
    There are many calculators available to do this. One is at:
    http://www.srh.noaa.gov/epz/wxcalc/wxcalc.shtml [Broken]
    With this one you need to calculate Dewpoint temp first using the first moisture calculator then calculate the density altitude.
    BTW humidity when it is in a % is relative humidity.
    Last edited by a moderator: May 3, 2017
  4. Jan 23, 2009 #3
    I need an actual formula...not a calculator
    calculator doesnt do me any good in an excel spreadsheet...

    so whats the formula for dewpoint with known temperature and relative humidity
    and then once I have dewpoint how do I get to Density Altitude?
    Last edited by a moderator: May 3, 2017
  5. Jan 24, 2009 #4
    The formulas are on the site I gave you. There are also spreadsheets on the net that do what you want to do.
    As for Td some reports already include it.
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