Thunderstorms or lightning rod causes lag

As soon as it started to thunder, it caused major lag in my world. I am in bedrock beta, and am building a building on top of the newly generated mountains. Im not sure if it is the copper lightning rod that i placed, or just the thunder itself. As you see in the clip that I attached, it suddenly lagged and i tried to open my inventory, but I couldnt. I also died at the end, and my loot was at the bottom of a cliff. How interesting, because I didnt jump off of it,