The heat index (HI) or humiture is an index that combines air temperature and relative humidity in an attempt to determine the human-perceived equivalent temperature — how hot it feels. The result is also known as the "felt air temperature" or "apparent temperature". For example, when the temperature is 90 °F (32 °C) with very high humidity, the heat index can be about 105 °F (41 °C).

The human body normally cools itself by perspiration, or sweating, which evaporates and carries heat away from the body. However, when the relative humidity is high, the evaporation rate is reduced, so heat is removed from the body at a lower rate, causing it to retain more heat than it would in dry air. Measurements have been taken based on subjective descriptions of how hot subjects feel for a given temperature and humidity, allowing an index to be made which relates one temperature and humidity combination to another at a higher temperature in drier air.

The heat index was developed in 1978 by George Winterling as the "humiture" and was adopted by the USA's National Weather Service a year later. It is derived from work carried out by Robert G. Steadman. Like the wind chill index, the heat index contains assumptions about the human body mass and height, clothing, amount of physical activity, thickness of blood, sunlight and ultraviolet radiation exposure, and the wind speed. Significant deviations from these will result in heat index values which do not accurately reflect the perceived temperature.

Alfred Matthew "Weird Al" Yankovic (pronunciation: /ˈjæŋkəvɪk/; born October 23, 1959) is an American singer-songwriter, music producer, accordionist, actor, comedian, writer, satirist, and parodist. Yankovic is known for his humorous songs that make light of popular culture and that often parody specific songs by contemporary musical acts. Since his first-aired comedy song in 1976, he has sold more than 12 million albums (as of 2007), recorded more than 150 parody and original songs, and has performed more than 1,000 live shows. His works have earned him three Grammy Awards among nine nominations, four gold records, and six platinum records in the United States. Yankovic's first top ten Billboard album (Straight Outta Lynwood) and single ("White & Nerdy") were both released in 2006, nearly three decades into his career.

Yankovic's success comes in part from his effective use of music video to further parody popular culture, the song's original artist, and the original music videos themselves, scene-for-scene in some cases. He directed later videos himself and went on to direct for other artists including Ben Folds, Hanson, Black Crowes, and The Presidents of the United States of America. In addition to recording his albums, Yankovic wrote and starred in the film, UHF, and television show, The Weird Al Show. He has also made guest appearances on many television shows, in addition to starring in Al TV specials on MTV.

Stefani Joanne Angelina Germanotta (/ˈstɛfəniː dʒʌrməˈnɑːtə/ STE-fə-nee jurr-mə-NAH-tə; born March 28, 1986), known by her stage name Lady Gaga, is an American singer and songwriter. Born and raised in New York City, she primarily studied at the Convent of the Sacred Heart and briefly attended New York University's Tisch School of the Arts before withdrawing to focus on her musical career. She began performing in the rock music scene of Manhattan's Lower East Side, and was signed with Streamline Records by the end of 2007. During her employment as a songwriter for the record company, her vocal abilities captured the attention of recording artist Akon, who signed her to his label Kon Live Distribution.

Lady Gaga came to prominence as a recording artist following the release of her debut album The Fame (2008), which was a critical and commercial success that topped charts around the world and included the international number-one singles "Just Dance" and "Poker Face". After embarking on the The Fame Ball Tour, she followed the album with The Fame Monster (2009), which spawned the worldwide hit singles "Bad Romance", "Telephone" and "Alejandro". The album's success allowed her to embark on the eighteen-month long Monster Ball Tour, which later became one of the highest-grossing concert tours of all time. Her most recent album Born This Way (2011) topped the charts of most major markets and generated more international chart-topping singles, including "Born This Way", "Judas" and "The Edge of Glory". Besides her musical career, she involves herself with humanitarian causes and LGBT activism.