supervene

/ˌsupərˈvin/
verb
  1. To happen unexpectedly, especially as an interruption or addition to an existing situation.
    • The picnic was going well until a thunderstorm supervened.
    • Their plans for a quiet evening were ruined when a power outage supervened.
    • New evidence supervened, forcing the detective to reconsider the case.
What does "supervene" mean? | whatsthatwordmean | whatsthatwordmean