Don't want to labor the issue. However, if the storm is a 3 or higher and hits your area I think you might want to follow Frank's idea. Safe rooms are only safe when it has a roof and walls. If the storm is bad enough, any destroyed window or door in the house will allow the pressure of the wind to enter and literally lift the roof off. In large storms you must protect the entire envelope of the house. That is how most homes in Miami were destroyed during Andrew...most folks boarded up portions of their homes or none at all. Hopefully I am speaking to the choir.