The only sewing I do during a thunderstorm is with my treadle or handcrank! I unplug my tv and all sewing machines. Had a direct lightning strike on the pole closest to our house and it actually melted the inside of my business phone. I don't talk on corded phones during a thunderstorm, either! Even a surge protector will not help if you get a direct lightning strike close by. The way it was explained to me, surge protectors only protect against the occasional surge of electricity that sometimes comes through the power lines and nothing will help if there is a direct lightning strike. The person who explained that seemed very knowledgable about electricity, maybe someone else has a different explanation...