Both.

Wyeth, Apples on a Bough, Study Before Picking, 1942

Dog days are over, and here comes September. Not Autumn, yet; simply September, which can be as sweltering as mid-July and as chill as late October, and usually manages to be both. Flowers still bloom in September, but sumac and swampland maples give them the lie by turning a gorgeous Autumn scarlet. 

Birds that we haven't seen or heard since June come trooping back with their songs ...

From New York Times, August 31, 1942

The scent of ancient apples, sun-warmed in an orchard.