Conversation so far:
what is the hottest it has ever been in arizona
Lake Havasu City reached 128 degrees on June 29, 1994, the highest temperature ever recorded in Arizona.
what is the hottest it has ever been in america
The hottest temperature ever recorded for the United States belongs to California. Furnace Creek in Death Valley hit 134 degrees on July 10, 1913.

Question: why was the temperature so high
Self-contained rewrite: why was the temperature so high in death valley