PC-12 Pilot reported an Engine Fire Warning Light illuminated and the aural bell sounding in cruise. The flight crew diverted to make a precautionary landing.

Narrative

Red Engine Fire Warning Light inflight; no other associated fire indications. During climbout from ZZZ; we were flying in IMC conditions in an area of scattered storms. While climbing through about 15;000 feet; we were in an area of light rain and encountered light turbulence. When we hit a small but noticeable 'air bump'; the Red Engine Fire Warning Light illuminated and the aural bell sounded. There were no other indications of fire or engine overheat. We elected to keep the engine running; but leveled off and reduced power to cruise power setting. We were northeast of ZZZ1; so we elected to divert to ZZZ2; as that was the closest major airport with long runways; instrument approaches; and crash crews. We stated our intentions with Center and [requested priority handling]. They gave us a vector toward ZZZ2 and handed us off to approach. Approach set us up for the ILS XXL. We completed all checklist items and commenced the approach. Following an uneventful landing; we cleared the active runway and shut down on the taxiway. As a precaution; we had all passengers egress the aircraft until we were able to verify that there was no actual fire in the aircraft. Post flight inspection of the engine bay showed no evidence of fire or abnormal heat. Of note; we have nothing but the highest praise for the professionalism of Center; Approach and Tower; and the Airport Fire Department.