I live in a mobile home and live in Tornado Alley. We cannot stay in our home when the storms are coming. I would say that learning to know the significance of the different storms categories and strengths will help you very much.
A storm watch in an alert to let you know that storms may happen.
A storm warning is an alert that a storm is in your area, may be same county or even 1-2 counties away. McDonalds often has your state map with the counties on the trays during this time of year. Get a clean one and put it on your fridge.
The new tor-con index is pretty good to me. It takes into consideration a lot of information that is very close to accurate. If you watch the weather channel or a local channel that has a good weather team then you can trust them to let you know if you are in danger. If you are truly not safe in your home due to poor design then find out what the neighbors do. There may be shelters on the property or nearby that some go to.
We go to the local hospital and go to their basement. If the winds are going to be over 60-70 miles per hour I am going to be gone before they hit and safe in a shelter outside of my home. We have had over 100MPH winds hit my house and had no damage but I am not going to take a chance that we get damage and hurt.
Find a shelter nearby that will be open if the storms are serious. Find out what the neighbors do. Decide what your family is willing to risk if there is a tornado in your area, sighted within 30 miles of you.