For those that have a hard time converting Celsius to Farenheit the math works out to: (C X 1.8) + 32 = F
So if it's 20C in Houston (lucky bugger Sikatri) that's (20C X 1.8) + 32 = 68F
The difference in the two systems is the delta between engineers and chemists and how they define absolute zero. Ask any chemist about absolute zero (where heat energy is 0) and and they will tell you it's -273 Kelvin. Ask any engineer and it's -460 Rankine. The Kelvin scale is where Celsius is derived and Farenheit follows Rankine.
From the web: "The Rankine (°R) scale is the absolute temperature scale related to the Fahrenheit (°F) scale, and both scales have the same size unit of temperature. The two scales are related by the equation °R = °F + 460. Thus freezing point of water occurs at 492 °R, whereas its boiling point occurs at 672 °R."
On the Kelvin scale water freezes at 273K (0C) and boils at 373K (100C).
Class dismissed.