You know the expression, “暑さ寒さも彼岸まで(Atsusa(warmth = warm days) Samusa (Coldness = cold days) 彼岸まで ( (last) till Higan-day).” I wrote in the last fall I guess. So we have two higan-days. Higan literally means “the other side of the river.” In this case, the river is the one that divides this world and that world (meaning the world for the dead). In Japan, it is believed that on this day, the ancestors can come to the other side of the river and we, the living, will go to the graveyard to greet them.
Anyway, the point it that I don’t know why but warm days usually end on the Higan in fall and we start to have more cold days and in spring after Higan, we start to have more warm days. Today, it was really warm!! Of course we have another wisdom expressions, “三寒四温” that means in the turn of the season we have 3 cold days and 4 warm days. So we might have a little cold days but we are certainly going toward spring and summer.