However, the plural of the Italian word scenario is scenari, making “scenarii” etymologically inconsistent. According to Merriam-Webster and the OED, the accepted plural of scenario is scenarios. The Corpus of Contemporary American English reports 3683 instances of scenarios being used and none of scenarii.
nouns - What is the plural of "scenario"? - English Language & Usage ...
The distinction is VERY subtle. And they're frequently used interchangeably. The scenario is the underlying setting. Essentially the background. The situation can mean the same. But, it also can mean what is going on at the current time (especially with regard to physical location of items). It implies a certain temporal or spacial understanding of the conditions at hand. What's the scenario ...