There is no definitive answer to this question as it largely depends on personal preferences. Some people might find states like Florida or California to be the hottest in the US, while others might prefer states like Arizona or Nevada. It really varies from person to person. In general, though, it seems fair to say that states located in the southern and western parts of the country tend to be hotter than those in other parts of the US. This is due to a variety of factors, including latitude (the closer a state is to the equator, the hotter it tends to be), elevation (states with lower elevations tend to be hotter), and proximity to large bodies of water (states that are closer to oceans or other large bodies of water tend to have milder temperatures).
