What region of the usa has the best year-round climate? And what region of the world does?

There is no region of the usa with the best year-round climate.

Nor is there a region of the world with the best year-round climate.

Why?

Because no criteria about what constitutes 'best' has been offered.

What's best for you may be major suck for someone else...amirite?

It really depends on what you consider "best".

Arizona has little rain, but it can get hot. But in the hills its relatively comfortable year round.

California is pretty nice, but it can get hot there and the pollution near any city is pretty bad (though San Diego is quite clean).

Some people love Hawaii, but it can get some torrential rains and storms (but they don't last very long). Plus its a volcanic archipelago, always the risk of earthquakes or volcanic eruptions.

Other people like Florida since its always sunny, but the summers are very hot, and its prone to hurricanes and flooding.

In terms of the world, every place is great for at least part of the year. No place is perfect all year.

Back in the 1950's, the director of the national weather service said the Southern part of Palos Verdes Peninsula, CA had the ideal weather. Specifically the area near Portuguese Bend. Of course it is subjective. Different people like different climates.

As far as the world....I don't know....probably a Mediterranean climate.

Florida, Southern Calif. Hawaii.

Queensland, Australia

Nipomo, California was written up as the best in the U.S. We lived there 3 years, and I think it's true. Then we decided we wanted more variety, and moved to Colorado.

"best" is meaningless without any criteria. best for what? and what are your preferences?