Questions about the representativeness of the KSLC observing site notwithstanding, below are the new records for Salt Lake City based on official records from the National Weather Service. Figures are from https://xmacis.rcc-acis.org/.
1. Highest average maximum temperature, 94.1˚F.
2. Highest average minimum temperature, 68.8˚F.
3. Highest average temperature, 81.5˚F.