What is the word for hot and cold weather? What is the symbol?

Suddenly warm but then cold

[zhà nuǎn huán hán]

[Explanation] Describes the climate in late winter and early spring, which is hot and cold, and hot and cold.

[Source] Song Dynasty Li Qingzhao's "Slow Voice" lyrics: "Looking for and searching, deserted, miserable and miserable. When it is warm and cold, it is the most difficult to breathe." Song Dynasty Liu Qingfu The lyrics of "Spring in the Jade House": "The willow tips are green and the little eyebrows are like seals. It is still undecided whether it is warm or cold.

”