There are more factors than just Altitude and Temperature
Most people commonly believe there are only two factors related to determining density altitude: field elevation and temperature. The belief that these are the only factors stems from the age-old use of the “density altitude chart” that every pilot encounters in textbooks, on tests, and in aircraft performance manuals.
This chart doesn’t tell the whole story, a pilot also needs to determine the effect on density altitude of humidity and atmospheric pressure.
In reality, humidity and air pressure also impact density altitude, however not to the extent of temperature and field elevation. Combined however the impact of these two factors can be significant.
Today, many of the electronic flight calculators include functions for calculating the actual density altitude. Additionally, there are several web sites with complete density altitude calculators such as the one created by Richard Shelquist that can be found at:
- Richard Shelquist Density Altitude Calculator