Summer was the dry season, the time of fruit and harvest. In Palestine it generally extended from April to October, when rain usually did not fall.
Scripture associates summer with gathering fruit, drought, heat, and the ripening of crops. “Summer” also occurs in descriptions of seasonal signs and of birds feeding on carcasses.
The dry season explains the biblical expression “drought of summer.” A “summer parlor” is literally an upper room rather than necessarily a separate seasonal building.