Move From Hot To Cold Weather

I come from Thailand, which is located in Southeast Asia. The weather in my country is very hot. However, in the winter, the weather in my country is very nice. It is a little cold. In contrast, when I came here in August, the weather was very hot. I think it was hotter than the weather in my country. Now, in the winter, the weather is very cold but I like it. When I walk outside, I have to run to get inside as soon as possible. I do not understand why America has very different weather in different seasons. I think it is because this country is very big and it has different climates in different areas. Thai people who live in America usually go back to Thailand in the winter because they are not used to living in very cold weather. For me, I can live in either America or Thailand.