What evidence do you see in the story that Granny Weatherall is hallucinating and becoming delirious in "The Jilting of Granny Weatherall"?

It is important to recognise the masterful way in which
Katherine Anne Porter uses the stream of consciousness narrative to show the
increasingly muddied and unfocussed thinking of Granny Weatherall as she slides ever
closer to death. This allows the way that her mind moves from one thought or memory to
another to be expressed and her disorientation to be revealed. Consider the following
example:

What
was it I set out to do? she asked herself intently, but she could not remember. A fog
rose over the valley, she saw it marching across the creek swallowing the trees and
moving up the hill like an army of ghosts. Soon it would be at the near edge of the
orchard, and then it was time to go in and light the lamps. Come in, children, don't
stay out in the night
air.

Notice here how Granny's
question and her inability to remember leads her to a memory of fog which in turn leads
her to the happy memory of the lighting of the lamps at twilight, surrounded by her
children. The narrative, just like Granny Weatherall's mind, skips from one topic to
another in free association that mirrors her hallucinated and deirious state. Note to
how in this quote the fog could symbolise the growing darkness of
death.