Why are tropical air masses warmer than cold air masses? What region is responsible for warm, humid weather at times during the summer in the Central Plains states?

What region is responsible for cool, humid weather at times during winter for eastern states?

What region is responsible for hot, dry weather during the summer in the desert southwest?

 Air masses are relatively large bodies of air that are fairly horizontally uniform in characteristics. They may extend across an entire continent and are relatively uniform in temperature and moisture content. The boundary separating two different air masses is called a front, and it is along these fronts that a substantial amount of our weather occurs.

Explanation:

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