There would be no seasons although there would still be air and water circulations between latitudes. The Earth's axis precesses, but precession does not put the axis perpendicular to the plane of orbit.
Whether an asteroid impact could affect this geometry I have no idea but frankly a collision big enough to do so, would cause us far more problems than that.
[Edited to insert a missing but important "not"!]
This post was edited by Durdle at December 25, 2016 3:09 AM MST