Is food in your fridge safe after a power outage?

Food in a closed refrigerator stays safe for about 4 hours after the power goes out, according to the USDA. A full freezer holds its temperature for about 48 hours (about 24 hours if it's half full), as long as you keep the door shut.

After that, the deciding factor is temperature. Perishable food that has been above 40°F for more than 2 hours should be thrown out. Here's how to tell what's safe, what to toss, and how to buy yourself more time before the next storm.

How to keep food cold longer during an outage

Keep the refrigerator and freezer doors closed. Every opening lets cold air out, and the time limits above assume the doors stay shut. Decide what you need before you open the door, grab it, and close it.

Before a storm, a few steps add hours:

• Set the fridge and freezer to their coldest settings a day ahead.
• Freeze water bottles, jugs, or ice packs and pack them into empty freezer space. A full freezer stays cold longer than a half-empty one, and the frozen bottles become drinking water later.
• Group frozen foods together so they keep each other cold.
• Move items you'll need in the first day, such as drinks and snacks, into a cooler so you don't open the fridge.
• Buy or make ice for coolers before the storm. Stores sell out fast once a storm is forecast.

Our hurricane supply checklist includes coolers and ice alongside the rest of your kit.

How to check whether food is still cold enough

Put an appliance thermometer in both the fridge and the freezer before hurricane season. The USDA says a refrigerator should be at 40°F or below and a freezer at 0°F or below. During an outage, a thermometer is the only reliable way to know what happened inside while the power was off.

If you didn't have a thermometer in place, use a food thermometer to check individual items when the power returns. Never taste food to decide whether it's safe. Food can look and smell fine and still carry bacteria that cause illness.

What to throw out from the refrigerator

Throw out perishable foods that have been above 40°F for more than 2 hours. Those include:

• Raw or cooked meat, poultry, and seafood
• Milk, cream, yogurt, and soft cheeses
• Eggs and egg dishes
• Cooked leftovers, casseroles, and soups
• Cut fruit and prepared salads
• Opened baby formula

Some foods hold up better without refrigeration. The USDA's charts list hard cheeses, butter, whole fresh fruits and raw vegetables, and condiments such as ketchup and mustard among the items that are generally safe to keep. Check the full charts on FoodSafety.gov for anything you're unsure about.

When you can refreeze food from the freezer

You can safely refreeze thawed or partly thawed food if it still contains ice crystals or has stayed at 40°F or below. Quality may suffer (some foods turn soft or watery), but the food is safe. Food that has thawed and sat above 40°F for more than 2 hours should be discarded, not refrozen.

Medicines that need refrigeration

Some medications, including insulin, need to stay cool. Ask your pharmacist before storm season how long your medications can be stored without refrigeration and what to do if they get warm. Don't guess. If a refrigerated medicine may have been damaged, call your pharmacist or doctor for advice before using it.

Food that touched floodwater

Throw out any food that came into contact with floodwater, including food in plastic containers, cardboard boxes, and jars with screw-on lids. Floodwater can carry sewage and chemicals. The USDA and FDA say commercially canned foods in undamaged cans can be saved if you remove the labels, wash the cans, and sanitize them before opening. Throw out cans that are dented, bulging, or rusted.

Running the fridge on a generator

A generator can keep a refrigerator running through a long outage, but it has to be run outdoors, away from the house, and never plugged into a wall outlet. Read our generator safety basics before you start one, since carbon monoxide from generators is a leading danger after storms.

Clean water for cooking and washing

If your water supply is under a boil-water notice, use stored or treated water to wash hands, dishes, and produce, and to mix baby formula. See how much emergency water to store for how much to keep on hand and how to treat water if you run short.

The rule to remember

When in doubt, throw it out. Replacing a fridge full of food costs money. Food poisoning in the middle of a storm cleanup, when doctors' offices and pharmacies may be closed, costs far more. For full charts and current guidance, check FoodSafety.gov and the USDA's food safety pages, and follow instructions from your local health department.

This is general guidance based on USDA recommendations. Follow your local health department and emergency management office after a storm.