Smoke from wildfires in Canada has drifted into the U.S., prompting air quality alerts for Americans as it continues to spread. But when officials and forecasters classify a city's air as "unhealthy" ...

The temperature is not the only thing that can impact how hot it feels outside — the amount of moisture in the air also makes a difference. The more moisture in the air, the hotter it will feel in the ...

It's always important to protect yourself from UV radiation to avoid getting burned and damaging your skin. One way to plan for your safety outside is by checking the UV index. (Photo Credit: E+/Getty ...

NEW YORK (WABC) -- The Air Quality Index is a scale used for daily reporting of how clean or polluted the air is, and what health effects might be of concern. The AQI focuses on what you might ...

The heat index measures how hot it really feels outside. The heat index is calculated based on air temperature and relative humidity. The National Weather Service will issue alerts when the heat index ...

The lipstick index theory was developed by Leonard Lauder, the chairman of Estée Lauder, in 2001. During the 2001 recession, ...

The Dollar Index is a long-running measure of the value of the U.S. Dollar against a variety of other fiat currencies. Investors can trade ETFs based off the index's movements, along with using it as ...

Forbes contributors publish independent expert analyses and insights. Catherine Brock covers personal finance and investing. In a perfect world, stock prices would always reflect underlying value. But ...