What do you mean by hot dead mice?

This proverb says that the summer heat has not yet come out, and when it is hot, the mice in the hole will die of heat.

Summer heat is the14th solar term among the 24 solar terms, that is to say, in late summer and early autumn, but the sun is still running in the tropic of Capricorn, and the heat radiated by the sun is greater than the heat emitted from the ground, so the summer heat has not disappeared. As the saying goes, "It's not summer, but it's summer in beginning of autumn", which means that it's normal for the temperature to be too hot during the summer heat, but at this time, the summer heat begins to weaken, and people will feel cool sooner or later.