Exploding Soap

We are snowbirds that live in Arizona during the winter months. We just arrived to our home to discover our Gains 4.4 L of laundry soap had cracked in the bottom creating such a mess that it took us 4 hours to clean up. the soap had hardened on the shelves and floor. I read all I could find on the package and nothing warning us of hot Arizona temperatures affecting the product. Obviously heat will perhaps expand to the point of eruption. Is this normal? If not, we should be warned of such an incident from happening. This was not a cheap bottle. I would be interested to hear from you. thank you