All temperatures are in degrees centigrade.
While cooking supper tonight I heard the weatherman on the television in the next room say that the the temperature somewhere was twice as hot as the average for that day and it rubbed me the wrong way.
Let’s say that the average historical temperature was 9° and it turned out to be 18° today. 18 is double 9 numerically but is it twice as hot? No. In absolute terms, a jump from 9°C to 18°C is an increase far smaller than the 100% claimed by the weather man; it’s more like 3.19%