Up until a month ago BLM land was all I shot on. It's free and you can bring your own stuff to shoot. Steel, cans, whatever. Just make sure you clean it up after or you won't have to worry about fire warnings. They will shut it down due to the garbage.
+1 for Rio Salado. When I was in the east basin that was my go to range. Yes it is hot here, but the benches are covered. I have gone there many times in the 100+ and have never been uncomfortable. Just remember to always have water with you. That goes for anything you do here though. If Rio Salado is your closest range I would highly recommend getting the membership. $85/year for unlimited free range time. I would also recommend paying the extra $15 for the early access gate pass. Range opens at 7am, the pass lets you in as early as 6am. You get in and setup before the lines start. $100 for that deal cannot be beat anywhere.
I am now in the north basin and Ben Avery is my go to range
for now because of the fire warnings. Another very nice setup, but they only offer daily rates, no memberships. Rod and Gun Club is membership only except on weekends they offer daily rates for the public. Those are the 3 outdoor ranges here. All very nice. There are also plenty of indoor ranges around if you don't mind spending the extra money. I would rather spend $7/day and be a little hot than $15/hour. There are tradeoffs. Indoor has AC, but outdoor has fresher air. Also my wife went to an indoor once and won't go again because it is just too loud for her even with ear plugs and muffs. Outdoor she has no problem.
As far as the fire warnings.
This is why they are there. Something with the electric lines out there started a fire and shooting got postponed most likely for the duration of the summer. I saw it happen. I was out there that day shooting at the far end of the allowed area. I finished up and was heading out and by the beginning of the allowed area I saw some smoke underneath the huge power line tower up the hill. Then a couple Sheriffs trucks passed me going in. Turns out it was a small fire about 2 miles off the road and burned a little over an acre. I went back a couple weeks later and the "FIRE WARNING NO SHOOTING" signs were posted.