What I expect to happen when there is lightning is that it creates some fires, but rain or time puts the fires out.
What really happened was when the lightning created fire, the fire would never go out. Rain did not put it out, and it burned forever. It was also able to hurt the player. This only happens when you have "/gamemode doFireTick false" If you have "/gamemode doFireTick true" this bug does not happen.
Steps to Reproduce:
1. In a single player creative world open up the chat bar by pressing T.
2. type /gamemode doFireTick false
3. then type /weather thunder
4. When the lightning starts is should make fire that never goes out and never spreads.