I would greatly appreciate it if you could please help me. This means you have every reason to fear a tornado really looming on the horizon one day. But, like most tornado dreams, yours apear to carry a broader meaning as well. Tornadoes in dreams consistently represent fears of separation from our families. Or if it, more likely, is due to the fact that, during a tornado, our immediate thoughts and concerns are to locate and assure the safety of our families - as soon as possible.
Tornadoes also are sudden storms.
They are hard to predict, and the devastation that trails in their wake is severe. Given the background you have provided, we know that both these metaphors may be at work in your dreams. At the same time, you lost your grandmother, with whom you were very close. Another emotional storm. If you are looking forward, ask yourself what new emotional storm it is that is looming on the horizon.