三伏
Meanings
1. the three annual periods of hot weather, namely 初伏 (chūfú), 中伏 (zhōngfú) and 末伏 (mòfú), which run consecutively over a period from mid-July to late August
Characters used
Examples1
近来 进入 三伏 天 了。
Lately, we've entered the dog days of summer.