in reading temperatures that are below zero degrees, it is recommended to avoid redundancies such as minus fifteen degrees below zero.
However, sometimes you hear or read in the media phrases such as “He reported that this weekend temperatures will drop to minus one degree below zero” or “Fourteen municipalities woke up with temperatures of minus eight degrees below zero.”
In the representation of figures of the type –15 °Cwhich express that the temperature is below zero degreesit is appropriate to use expressions such as fifteen degrees below zero o minus fifteen degrees, and not the redundant way minus fifteen degrees below zero.
Thus, the appropriate thing in the previous examples would have been to write “He reported that this weekend the temperatures will drop to minus one degree” and “Fourteen municipalities woke up with temperatures of eight degrees below zero.”
On the other hand, although it is not uncommon to find phrases like “Frozen night of up to four degrees negative”, the use of the construction is discouraged negative degreessince the negative is the number, not the unit of measure.
See also
➤ degrees of temperature, writing keys