One account accord during Hurricane Katrina when a young man killed his girlfriend in a grizzly manor then killed himself. Many believe the hurricane stirred up the spirits in the very haunted French Quarter of New Orleans and drove him to it or took control of him to do something he would never do.
Several in the paranormal field, including myself, have seen heightened activity just before and during storms. So, saying the weather can affect the spirit world by giving them more energy is easily agreed upon and it might even weaken the living and be more easily controlled by the dead.