• Featured by Apple App Store in Weather > What’s Hot for the iPad in 108 countries.

The Heat Index & Heat Category is the Universal App for measuring the perceived temperature.

Because the body normally cools itself by perspiration, when relative humidity is high, the evaporation rate is reduced, and heat is removed from the body at a lower rate causing it to retain more heat than it would in dry air.

This calculator takes into consideration not just the air temperature, but also the relative humidity, giving a good estimate of the perceived temperature when the the air temperature and relative humidity are entered. The heat category is a measurement taken from NOAA's National Weather Service Heat Index Chart and is used to assist in determining how much caution should be exercised when outdoors for any period of time.

The results can also be emailed through the iPhone / iPod Touch / iPad's email application using a prewritten template.

The answer is computed for both Fahrenheit and Celsius for convenience.

The calculator is the most effective when the temperature is at least 80 °F / 26 °C and the relative humidity is at least 40%.

This app features:

• Send your calculations or conversions by email
• Universal App (iPhone, iPod Touch, and iPad)
• iPhone 5’s 4 inch screen and the original 3.5 inch screen are supported
• Retina Display graphics
• Fast app switching
• Automatically Saves Your Inputs
• Latest version of iOS is supported

Press the FETCH button to get your location calculated HEAT INDEX for the iPhone, iPad, and iPod Touch. Then try calculating your "What if's" by changing the values.