Um...no it isn't. The film is clearly set in the fall. Is the author confusing this movie with Independence Day?
That article really has a Lyndon Larouche feel.
Good catch. It's still possible, since the premise is that they go on a long walk from circa Albany to Boston, with how many days in that house?, and other delays not shown to end up with the leaves just starting to fall in Boston (October). Perhaps the confusion by the author came from having so many flags flying on the porches of the rowhouses (and so many people with mixed clothing, some Fall-like, like the girl and mother, but many others with summer street clothes and no jackets in the early scenes).