The simple answer is that you improvise. Your goal is survival and you make do with what you have. At this point, health is no longer your primary priority. It is better to eat something, even junk food or processed food, than to go hungry during a storm. (Related: Improvising while prepping: Everyday items that can double duty in an emergency.)
Bread, especially freshly baked bread, might sell out quickly in an emergency since it is a staple food. You don't really need a loaf of bread to prepare sandwiches. With a little creativity, you can substitute bread with hamburger or hot dog buns. You can also use pita flatbread, tortillas, bagels, muffins, and crackers.
It might be a highly unlikely scenario but, in case your grocery store runs out of water, other beverages can help you avoid dehydration. You can get electrolytes from sports drinks, such as Gatorade. Other suitable drinks include flavored or sparkling water, juice boxes or bottles, vegetable juices, and premade iced tea. You can also buy soda pop in small amounts. Limit the soda pop as too much of it might dehydrate you even further.
In case you still have potable running water at home, buy any food-safe container that you can fill with water. You can buy plenty of these containers and use them to store your emergency water supply.
If your supermarket runs out of canned food, you can always buy fresh fruits and vegetables. They won't last as long as canned goods, but they can stay fresh long enough to last the storm. Canned pasta meals, soups and chili usually are the first to go out of stock. If you need to find prepackaged meals that you can easily heat up, you can try looking at the International Food aisle where you can find soups and noodle bowls. Other canned goods you might find there are salsa or enchilada sauces, fish, potatoes, mixed vegetables, refried beans and baked beans.
You can also look at other aisles for suitable shelf-stable foods. Some aisles may even have individually packed school lunchbox food items. Be on the lookout for food items such as pudding, applesauce, precooked rice, peanut butter, breakfast cereals, granola bars, beef jerky, vegetable chips, potato chips, fruit cups, shelf-stable yogurt, Vienna sausages, and precooked bacon.
Having an alternative source of light is better than sitting in the dark. If you can't find flashlights or emergency candles, you can always look for scented candles, tealight candles, decorative jar candles, headlamps, and LED shop lights.
If your local grocery somehow runs out of batteries, there are other nontraditional stores where you can find them. You can head to your nearest hardware store, home decor store, toy store, corner store, drug store, or dollar store.
If you want to learn more about staying prepared for emergencies, you can read more articles by going to Preparedness.news.
Sources include: