The reason we are keeping distance has to do with Science. The length of a meter is constantly changing in tiny increments that would eliminate any accuracy in science over the course of year, decades... and since all of Metric is tied into the distance of meter's the entire system gets skewed. So the global standard in science, for distance, is miles.
But the OP asked about temperature, not volume, mass, or distance. Centigrade converts directly to Kelvin so that has more relation to science, as well as relating directly to calories.
So to make it somewhat simple, Fahrenheit has the freezing point of distilled water at 32؛ rather than 0؛C, and the boiling point at 212؛ rather than 100؛C. So we can subtract 32 from the Fahrenheit temperature to get a range of 0-180 rather than 0-100؛C.
To convert ؛F to ؛C x-32 = y and 5*y/9 = temperature in Centigrade. Simple.