Adding to what Hank posted, it was Memorial Day weekend, and it was a rainy weekend. Lots of people at the movies. (new James Bond movie - View to A Kill and, IIRC, Rambo also making it a BIG movie weekend).
I would like to know where her car was in the lot, if it was at the south end she could have been meeting someone at the Dolly Madison Apartment tower. However, I think the simplest explanation is the most likely, she was meeting her soon to be ex husband there so she could pick up her toddler son, they argued and it ended badly.