It’s called hypnopompic hallucination.
Unlike with sleep paralysis, you can move and talk while still seeing it and it will last a few seconds up to a minute which can seem like an eternity.
It usually fades as soon as you turn on the light, but for some very few people it does not and persists even after turning on the light.
Here’s an example of someone who often experiences these and has started recording themselves: https://youtu.be/bEMGZNvETMQ
Why YSK: because it’s very scary and unsettling when it happens and since you can move you don’t believe it’s sleep paralysis and can’t explain it. This might explain many of the “monster or spirit at the foot of my bed” sightings that we often hear mentioned in horror podcasts.
This is almost definitely the case with ghost and alien abduction stories.
Well, that and carbon monoxide poisoning.
Don’t forget about the rarer, but super cool weird physical phenomena like ball lightning and swamp gas!
Important to include those explanations that aren’t just psychological/hallicinatory phenomena, I feel.