The two primary causes of civil aviation crashes; fuel mismanagement (running out of gas) and flying into conditions you are not prepared for e.g. weather. Saturday’s weather in that area was iffy and deteriorated badly in the late afternoon. The Cherokee is a nice little plane but not for adverse conditions.
I live in Florida, where weather is notoriously changeable and hard to predict. When I go flying with family members who are recreational pilots, plans are always contingent on the weather. Even at that, depending on the time of year, it is astonishing how quickly the sky can go from clear to marginal to nasty.