I don't recommend Sacramento in June.
The day I graduated HS there it was 114. Still over 100 after midnight.
I left town shortly after HS and didn't go back for 10 years. Then I discovered it was the easiest place to make good money, and got a start on putting away some real savings. (Another hot spell. I got a good job in construction because all the experienced local construction workers had already made a years wages and disappeared to Hawaii, Tahoe, etc so I walked into a labor shortage. That's how hot it gets. I sweated off a few pounds myself. Well worth it.)
It's simply a place where decent people work hard and get along with each other.
Forget outdoors activities after noon if you are there during a hot spell. Not only hot, but the Central Valley traps smog (local and from the Bay Area) during the hot spells so soon your lungs burn. However if you happen to hit moderate weather, then it is nice.
It's a company town (state government, maybe like Albany NY). If you have local family or friends then there is always something going on, like anywhere. As a lonesome tourist, not so much.
The Railroad Museum is truly world class. Sacramento was the terminus of the original transcontinental railroad and remains a major rail (and truck freight) hub. The museum is in Old Sacramento, sometimes described as a tacky and harmless reconstruction of what Sacramento was like a few years after the Gold Rush - tourist trinket shops etc and a waterfront promenade not much different from what we saw in Omaha.
The locals all get out of town on the weekend due to the heat. It's a local saying that Sacramento is two hours to anywhere. Realistically, East into the Sierras, or West to the Bay Area and San Francisco.
Popular destinations include the Sierras (you might take a gambler's special bus package tour to South Tahoe, or to Reno), a package tour of the wine country (Napa and Sonoma County) or take Amtrak to San Francisco and wander the city. That is what I would find most interesting - SF is endlessly fascinating. (No car needed for any of these but it would be a minor convenience). Or Amtrak over the Sierras to Reno. That is a gorgeous and fascinating trip, and lodging is cheap in the mega-casinos. If you get a car and choose to drive up the Sonoma County coast (1.5 hours north of SF, gorgeous) then stop by my apple orchard!
You will see enough of Sacramento in the evenings to realize you won't miss anything going away for the weekend.
Music Circus is unique evening entertainment. They combine classic stage plays (Gilbert & Sullivan etc) alternately with modern stuff. Located downtown. BTW it's a geographically large city and you would need a car if your work is anywhere but downtown.
Other evening activities are same as any midsize city - an Imax movie house for example. I used to spend a lot of time in Los Angeles on travel and there was far more to do than Sacramento offers - Sacramento is simply a go home to your family kind of place.