Hello, fellow Californian!

Petaluma to Surprise is going to be a big change.
There are two summers here: dry summer followed by wet summer. Dry summer is unbearably hot and the humidity drops down to 2-3%. Wet summer is also unbearably hot but more humid. That's when the monsoon storms come to cool things off a little. It's easier to cool chickens down when the humidity is lower (dry summer) than when it's higher (wet summer).
Your first summer will be hit and miss. Try different things out to figure out what works best for you and your chickens. I go into summer mode when temps hit 90F or when the chickens start panting, whichever comes first.
I make ice blocks using
these trays.
I freeze them and keep a big stack in our chest freezer, ready to go. I scatter them throughout the pens and change them out every few hours when they melt. I also put ice in the waterers. Some people like to add a supplement to water, like
this one.
I don't use metal waterers, feeders, or nest boxes. They get way too hot in the summer. I have one metal waterer that I use in winter because I can safely heat it (I don't like to use heaters on plastic).
I freeze water bottles of various sizes, 20 oz. to 2 liters, and distribute those throughout the run. The chickens like to lay next to or on them to cool down. Those bottles are also kept ready to go in the chest freezer and replaced throughout the day.
Everyone I know with chickens have runs and coops that are completely covered. You can't have too much shade. Even in a completely covered run they will still get sufficient sun in winter.
I use heavy-duty waterproof 16 mil tarps as covers because they're easy to attach to rounded roofs. White reflects the sun well. Many people use corrugated
polycarbonate or
steel panels for roofs. Those are more expensive but much more durable than tarps.
I use these
standing misters.
Don't set it up the way it looks in the photo, that looks like a snake to chickens and can frighten them. It's bendable so you can set it up any way you like. I wind them around the inside of the run fence.
Many people use these
hose misters for all kinds of livestock enclosures: chickens, ducks, horses, etc.
Make sure your barn and run can stand up to
Arizona storms. The winds can be vicious. I'm just outside of Tucson and we had a tornado last year that completely destroyed our yard, fence, and part of our house's roof. The tornado was an EF1 with wind speeds between 86 and 110 mph. It
obliterated our run - there was literally nothing left.
I'd never seen anything like it in my life. I didn't know it was a tornado, there was no warning. I only knew it was an extremely violent storm.
At that time the coop was in a slightly more protected area near some buildings. My roommate and I were able to get the hens into the coop and we stood outside in the storm and protected it as best we could. The hens survived but it was a terrifying and dangerous experience, not something I care to repeat!
I have temporary pens now and I'm rebuilding a permanent coop and run over the next few months. The new run and coop will be attached to t-posts anchored deep in the ground in cement. Above the ground they will be anchored to concrete block walls.
Watch your birds in the summer and monitor their appearance and behavior for any signs of heat stress. Having cameras in the coop and run helps a lot with this. I use
these Reolink cameras. They stand up well to our weather. I just keep a camera window open on my desktop computer as I work and check it regularly.
Have a system in place for any birds who look like they're suffering in the heat. You want to catch it early. I keep six "hospital" cages set up in the coolest part of our house. These are 18 gallon tubs with pine shavings, cups for food and water, and a screen lid. Last year we needed to bring hens inside two or three times during the summer. They recovered quickly once they were in cooler temps.
That was their first summer and everyone survived. Sometimes chickens die in the summer. Don't blame yourself if that happens. Arizona summers are beyond extreme and there's only so much you can do. Just do the best you can.
Our coop is a long rectangle shape and the long sides are 1/2" hardware cloth, only the ends are solid wood. Ventilation is key. It's next to impossible to have too much. I have a tarp over the coop to keep the rain off and provide additional shade. In winter I cover the hardware cloth with boards to block the wind, when needed.
Build your coop and enclosure to keep out predators and pests. Coyotes and wildcats are perfectly capable of jumping 6' walls and fences and they hunt in urban areas. Mice and wild birds will eat your feed and squirrels will steal feed and eggs. Build with all of these in mind.
Many people put fans around and in their coops and runs in summer. Air movement helps a lot. I use a
floor fan and a
pedestal rotating fan.
Obviously these need to be well protected from the rain and storms. Some people attach air conditioners to their coops (I haven't but I'm considering it).
I freeze berries, fruit, and peas and give those as treats during summer, the chickens love them. You can also freeze blocks of ice with treats like fruit and vegetables inside. The chickens will peck at them to get at the treats, that gives them something to do in addition to cooling them off.
Good luck with your move! Ask questions any time!