Types Of Fever A low-grade fever happens when the body temperature rises to 100.4F (38C) Moderate fever if the temperature rises above 102.2-104F or 39.1-40C. High-grade fever indicates if the body temperature is 104F (39.4C) or above. Hyperpyrexia, if the temperature is above 106F or 41.1C. Aug 31, 2020