He explained that when a person dies, body temperature drops about 1.5 degrees every hour, on average, depending on the temperature of the environment the body is kept in. If a person dies in a 70 degree room, 10 hours later, pathologists would expect the body temperature to have dropped about 15 degrees. And that would speed up if the body was placed in a cold environment or slow down in a warm one. Although it’s not clear if Rainey’s body was put into refrigeration in the medical examiner’s office before these photos were taken, that would be a standard procedure, Baden said. That means that if Rainey’s body temperature was still 94 degrees roughly 12 hours after he died, his body temperature may have been as high as 109 degrees when he died.
Source : http://www.huffingtonpost.com/entry/darren-rainey-inmate-death-dade-correctional-institution_us_58d94c9fe4b03692bea82e1b