I've heard that is a storm is really looking to be bad -
unplugging all expensive electronics is best.
refrigerator, TV, microwave, computer, etc.

Just turning them off doesn't always protect them.
The power spike/surge can travel thru the lines sometimes.

It doesn't happen very often but when it does it's expensive to replace those things.

It happens here every few years, someones tv explodes or something...
the home wasn't grounded or had other wiring issues.

but if it's bad I unplug to be safe until the storm is gone.

Thank you very much ladies. Your answers are much what I expected, but I wanted to be sure.

As we live in rented accommodation I have no idea if the house is "grounded" or not. I didn't know you could get separate surge protectors but I run my computer etc via a power box with an automatic cut off switch. I'll look into surge protectors for the house.

We were living in an area where big electrical storms were common, so I got used to unplugging everything in the house when they were around.

Thank you again. Your replies were very helpful.