It is recommended that families have enough drinking water for seven days, one gallon per person per day. Jugs and buckets can also be filled for washing and toilet flushing. Families should have enough food on-hand for seven days, non-parishable items in airtight containers are recommended. Don't forget the can opener.
Make sure to have a battery-powered radio and plenty of extra batteries and gather prescriptions, medications and extra eye glasses. Gather important documents like: birth and marriage certificates, insurance policies, passports etc., you can keep them in Ziplock bags for dry storage.
You may also need to prepare kit with dry clothes, toiletries, and blankets if you are asked to evacuate. Tools, cash, a whistle, camping gear, and plastic storage boxes are also recommended for keeping stuff safe and dry.
The Red Cross publishes a comprehensive checklist that can be accessed from the link.
