If you like the heat then by all means go in the summer. I have stayed in Williams and taken the train, it was awesome. And I have camped White Horse Lake and it was awesome too! Be aware that summer is monsoon season and it rains almost daily. Although it can be over in a few minutes, it varies. Last October we went to 'Bearazona' which is in Williams or very close and it was cute....a few animals, I'm sure it's grown by now. You drive your car through a small park with animals loose, reminds me of Lion Country Safari but on a miniature scale. Have a great time!!!!