Alternative to "daydream" without the pleasant connotation

I am looking for a word that means something like "daydream" or "fantasy", but without the connotation that I actually want this "imagining" to come true.

For example, something that would fit the sentence "I was on the bus today, and fantasised that the bus crashed and I had to decide who to save first."

Fantasise sounds a touch too sexual to me.

Daydreamed makes it sound like wishful thinking, something I hope will come true in the future.

Imagined is close, but doesn't have the same sense of running through the scenario in detail in my head in the way the other two do. This part is important.

Any other ideas? The sentence can be rephrased as required.

"Visualized is pretty neutral - could have positive or negative connotations.

I was on the bus today, and envisioned the bus crashing and deciding who to save first.

envision:

verb

[WITH OBJECT] Imagine as a future possibility; visualize:

contemplate

1. [TRANSITIVE] to consider doing something in the future

   • a. to consider the possibility of something happening

     We’re not even contemplating defeat.

     The alternative is too horrible to contemplate.

     Synonyms and related words

     To imagine, or to use your imagination:imagine, suppose, think up...

That definition brings up another suitable word:

suppose

Here's a news item that uses contemplate in the title

Emergency Responders Contemplate Train Derailment Disaster Scenario

Personnel from multiple law enforcement and emergency response agencies on Wednesday teamed up with officials with Burlington Northern Santa Fe Railway and Amtrak to consider what would happen in the case of a dangerous emergency train derailment. In the proposed scenario, a freight train possibly transporting hazardous materials and an Amtrak train derailed near the Southwest Washington Fairgrounds.

That story used another suitable word:

consider

I think to muse over someone or something can convey the meaning with a neutral connotation: (MW)

• to reflect or meditate on someone or something.

  • I often muse over the possibility to go and live abroad.
  • She is always musing over the fact she could have stayed single.

envisage

• To envisage is to imagine something that does not yet exist.

woolgather

• form a mental image of something that is not present or that is not the case.

(vocabulary.com)