NBC Action Weather Plus Calculators
Have you ever wondered how relative humidity affects how hot it really feels outside? Confused about what the dew point really is? You can learn all about these and other weather terms with our interactive NBC Action Weather Plus Calculators below.

Related weather definitions from NBC Action Weather Plus:

 • field elevation – the known elevation at the surface in feet MSL. Usually found on aeronautical charts for airports. Below is a list of nearby airports for our Arizona Weather Network locations:

Sedona: 4,827'	Flagstaff: 7,011'	Lake Havasu: 781'
Payson: 5,157'	Snowflake: 5,820'	Prescott: 5,045'
Globe: 3,235'	Casa Grande: 1,464'	Ajo: 1,458'
Yuma: 216'	Phoenix: 1,135'	West Valley: 1,085'

 • temperature – the amount of heat or cold measured on a thermometer.
 • pressure – the weight of the air above a given location from the surface of the earth to the top of the atmosphere.
 • dew point – the temperature to which air must be cooled for saturation to occur; the temperature at which dew or frost will form.

So what is Density Altitude?
Density altitude is an issue pilots must deal with when flying in the high country and/or when there are high temperatures and high humidity. Density altitude is defined as the pressure altitude corrected for non-standard temperature variations. A good rule of thumb to remember about density altitude is the 3 H's: Height, Heat, and Humidity. Altitude (height), temperature (heat), and humidity affect density altitude. The higher these factors are, the greater the density altitude, and a high density altitude is not a good thing for airplanes. Why? High density altitude affects an airplane's performance, specifically it's takeoff distance and rate of climb. So at high altitudes, high temperatures and high humidity, an airplane will require more runway distance for takeoff, and it will take longer for the airplane to gain altitude. If a pilot fails to anticipate high density altitude, s/he could easily run out of runway before lift-off, or fail to clear a ground obstacle such as a mountain. Simply put: Density altitude is the altitude the airplane thinks it is at, and performs in accordance with.

NBC Action Weather Plus Calculators:
 • Barometric Pressure Conversions
 • Cloud Base Calculator
 • Density Altitude Calculator
 • Dew Point Calculator
 • Fahrenheit / Celsius Conversion
 • Heat Index Calculator 1
 • Heat Index Calculator 2
 • Relative Humidity Calculator
 • Relative Humidity / Dew Point Calculator
 • Wind Chill Calculator
 • Wind Velocity

Learn more weather terminology here.