Is the first frost the last day of autumn?

The first frost is not the last day of autumn, but the day before beginning of winter is the last day of autumn. The first frost is the last solar term in autumn.

The first frost solar terms are characterized by cold weather in the morning and evening, hot weather at noon and large temperature difference between day and night. Because "frost" is a manifestation of cold weather and large temperature difference between day and night, it is named "first frost", which means "sudden drop in temperature and large temperature difference between day and night".

The first frost solar term, everything ends, ends, the sun goes down to the ground, and the yin begins to condense. The first frost does not mean "frost", but refers to the sudden drop in temperature and the large temperature difference between day and night. After the first frost solar term, the scene of late autumn is obvious, and the cold air goes south more and more frequently.

Extended data:

On the national average, the first frost is the season with the largest temperature difference between day and night in a year. The "first frost" solar term reflects the climatic characteristics of sudden drop in temperature, great change in temperature difference between day and night, and obvious dryness in autumn.