A few years back, we had a bad storm and I saw lightning hit a telephone pole across the street. It was a few minutes later and the neighbors came running over asking for help because their house was on fire. They were always scared of storms because the house that used to bewhere theirs is burned down from lightning. Anyway, they always unplugged everything, and I mean evertthing. In the kitchen, there was a can opener sitting n the counter, unplugged. There was a burn mark coming from the outlet, down the wall, acrosss the counter, melted the can opener, and continued across the counter to the sink. some of the outlets burnt up and all of the GFIs did. Washer and dryer sat side by side ... both were unplugged, the dryer fared well, but the washing machine was on fire! That was the only thing that stayed afire, we dragged it outside just as the fire dept. got there.
Anyway, moral of the story is, even if it is unplugged it may not be safe!