This group consists of people who live in tornado, hurricane, flood, wildfire, earthquake or heavy snowfall-prone areas and want to be prepared for possible emergencies. They invest in material for fortifying structures and tools for rebuilding and constructing temporary shelters. While assuming the long-term continuity of society, some may have invested in a custom-built shelter, food, water, medicine, and enough supplies to get by until contact with the rest of the world resumes following a natural emergency.
To me, the best option is to store emergency food. How much? If you have none, store enough for a few days. If you have enough for a few days, get enough for a week. How much you store depends on what time frame you think you're at risk for having to be completely independent. The early settlers of the southwest liked to store enough food for a whole year and still do to this day!