As the end of April draws near, most parts of the U.S. are safe from snow and ice storms that can cause power outages.

But in the summer months, you may face a blackout from heavy winds, thunderstorms or power system overload. You could even be dealing with a power outage caused by a car running into a utility pole as thousands of customers of CL&P in East Hartford, Conn., did on April 22.

Are you prepared?

Here are 18 tips from Ready.gov for what to do before, during and after a blackout.

Before a blackout

1. Build an emergency kit.

A disaster supplies kit is simply a collection of basic items your household may need in the event of an emergency. Try to assemble your kit well in advance of an emergency. You may have to evacuate at a moment’s notice and take essentials with you. You probably won’t have time to search for the supplies you need (buried in the basement) or shop for them.

In addition, basic services such as electricity, gas, water, sewage treatment and telephones may be cut off for days, a week, or even longer. Your supplies kit should contain items to help you manage during these outages in sufficient quantity to last for at least 72 hours. Local officials and relief workers will be on the scene after a disaster but they can’t reach everyone immediately. It could take hours or days to get help to you.

2. Make a family communications plan.

Your family may be in different places when disaster strikes, so plan how you’ll contact one another. Think about how you’ll communicate in different situations. Ready.gov suggests completing a contact card for each adult family member. Have them keep these cards handy in a wallet, purse or briefcase, for example, in addition to making sure that everyone in the family has the information stored in the appropriate smartphone, tablet and computer.

Don’t forget to complete contact cards for each child in your family. Put the cards in their backpacks or book bags.

Check with your children’s day care or school about their plans for dealing with a power outage. Facilities designed for children should include identification planning as part of their emergency plans.

3. Follow energy conservation measures to keep the use of electricity as low as possible, which can help power companies avoid imposing rolling blackouts. Get in the habit of turning off lights and electronics every day and setting thermostats higher or lower as appropriate.

4. Fill plastic containers with water and place them in the refrigerator and freezer if there’s room. Leave about an inch of space inside each one, because water expands as it freezes. This chilled or frozen water will help keep food cold during a temporary power outage, by displacing air that can warm up quickly with water or ice that keeps cold for several hours without additional refrigeration.

If you use well water instead of city water, you probably use electric well pumps to deliver water to your house. You can continue to use water for a little while, but when the reserve is empty, you won’t have access to fresh water until power is restored. Keep large containers of water available to flush toilets while the power is out.

5. Be aware that most medication that requires refrigeration can be kept in a closed refrigerator for several hours without a problem. If unsure, check with your physician or pharmacist.

6. Keep your car tank at least half full because gas stations rely on electricity to power their pumps. In a blackout or other emergency, gas stations may run out of gas, even if the pumps do have power.

7. Know where the manual release lever of your electric garage door opener is located and how to operate it. Garage doors can be heavy, so know that you may need help to lift it. Keep a key to your house with you if you regularly use the garage as the primary means of entering your home, in case the garage door will not open.

During a blackout

8. Use only flashlights for emergency lighting. NEVER use candles during a blackout or power outage due to extreme risk of fire. Battery-operated candles should be safe, but they may not provide as much light as a flashlight. Leave on one light so that you’ll know when your power returns.

9. Keep refrigerator and freezer doors closed to keep your food as fresh as possible. If you must eat food that was refrigerated or frozen, check it carefully for signs of spoilage.

10. Turn off or disconnect appliances, equipment (like air conditioners) or electronics in use when the power went out. Power may return with momentary “surges” or “spikes” that can damage computers as well as motors in appliances like the air conditioner, refrigerator, washer or furnace.

11. Use your generator safely. Don’t run a generator inside a home or garage. Don’t connect a generator to a home's electrical system. If you use a generator, connect the equipment you want to run directly to the outlets on the generator.

12. Listen to local stations on a portable radio or to a battery- or generator-powered television for updated information. Even though your smartphone, tablet and computer may have a long battery life, chances are your Internet connection won’t be available. You won’t be able to access your usual news channels, like Twitter or Facebook.

13. Do not call 9-1-1 for information—call only to report a life-threatening emergency. Use the phone for life-threatening emergencies only. If you do need to make a call, use a standard telephone handset, cellular phone, radio or pager if your phone requires electricity to work, as do most cordless phones and answering machines. Use the phone for emergencies only.

14. Take steps to remain cool if it’s hot outside. In intense heat when the power may be off for a long time, consider going to a movie theater, shopping mall or “cooling shelter” that may be open in your community. If you remain at home, move to the lowest level of your home, because cool air falls. Wear lightweight, light-colored clothing. Drink plenty of water, even if you do not feel thirsty. Be sure to provide plenty of fresh, cool water for your pets as well.

15. Put on layers of warm clothing if it is cold outside. Never burn charcoal for heating or cooking indoors. Never use your oven as a source of heat. If the power may be out for a prolonged period, plan to go to another location (the home of a relative or friend, or a public facility) that has heat to keep warm.

16. Eliminate unnecessary travel, especially by car. Traffic signals will stop working during an outage, creating traffic congestion. If you have to leave for a safer location, plan your route accordingly.

17. Elevators and escalators may not work during a power outage. If you have to evacuate the building, use the stairs or follow directions from emergency personnel.

 After a blackout

18. Throw away any food that has been exposed to temperatures of 40° F (4° C) for two hours or more or that has an unusual odor, color or texture. If you’re not sure food is cold enough, take its temperature with the food thermometer. If food in the freezer is colder than 40° F and has ice crystals on it, you can refreeze it.

Never taste food or rely on its appearance or odor to determine its safety. Some foods may look and smell fine, but if they’ve been at room temperature too long, bacteria causing food-borne illnesses can start growing quickly. Some types of bacteria produce toxins that can’t be destroyed by cooking.

When in doubt, throw it out!