Now we are entering the dog-days of July. In Salt Lake City, July features the least amount of weather variability of any month on the calendar, so when it comes to precipitation or cold fronts, we have to expect the worst.
However, there is some hope in the medium-range forecasts. The GFS, for example is projecting a bonafide cold frontal passage for Sunday, with 700-mb temperatures at Salt Lake City dropping to about +3C by afternoon, which would mean valley temperatures probably near 70ºF, although the high temperature for the day would probably be hither and occur earlier in the day due to the frontal passage.
If you really want to feel cold air, drive north and further under the trough where the mountains of Wyoming, Idaho, and Montana will be even colder. Higher elevations could even see snow under this scenario.
I've taken a quick look at the ensembles and while they haven't locked in on precisely how cool it will get, it does look like pleasantly cool air is in the way. Keep your fingers crossed that this comes to fruition.