If you are looking for a month to bet on for near or above average temperatures in Salt Lake City, July is your best option. July features the smallest amount of year-to-year temperature variability of any month of the year. This, combined with the gradual increase in global temperatures, means it's pretty hard to have July that is substantially below average unless something really exceptional happens.
Below is the average July temperature for Utah Climate Division 3, which covers the Wasatch Front. One can see the overall warming trend since 1895, which reflects a surge of warming prior to about 1940 and then after the late 1970s. These two warming surges are also apparent in globally average temperatures (not shown). Year-to-year fluctuations are only about 3-4ºF on average. The grey line is the 1981-2010 climate average and we haven't had a year significantly below it since 1997. Ah, the good old days.
Of course, there is always the potential for a black swan event. July 1993 is a good example as it is easily the coldest July in the instrumented record in northern Utah and a full 4ºF colder than any July since 1915. Several factors came together in 1993 to give us an unusually cold summer. The first was the eruption of Mt. Pinotubo, which dropped temperatures globally. The second was a weaker-than normal circumpolar vortex, which enabled cooler air to spread more frequently from the high to the low latitudes. The third was a strong negative phase of the PNA pattern, which put persistent troughing over the interior west. See A Tale of Two Summers: 1993 vs. 2013 for more discussion.