What is the antonym of midsummer?

Severe winter, poor winter, deep winter

Explain in detail:

Midsummer is the hottest time in summer. Midsummer, the term of solar terms, is actually midsummer. In ancient times, it was divided into Meng, Zhong and Ji. One of these three months is the hottest time in summer. At this time, many fruits and vegetables are ripe. In midsummer, the weather is hot, and old people and children are prone to heatstroke. Therefore, in life, we should adopt a scientific diet, reasonably relieve summer heat and keep healthy.