Severe storms moved through the Cincinnati area Monday night, bringing heavy rain and strong winds that downed trees and power lines, leaving tens of thousands without power.

And as we know, when the power goes out, all perishable food in the refrigerator and freezer is at risk of going bad, and it may not be safe to eat even after power comes back on.

Here's what food safety experts recommend we do before, during and after a power outage.

Stay inside:Excessive heat warning Tuesday, hot temps and heat index values up to 109

Photos:Severe thunderstorms roll through Greater Cincinnati, June 13

To help best prevent food wastage during a power outage, the Centers for Disease Control and Prevention recommends keeping appliance thermometers in the refrigerator and freezer. The refrigerator should be kept at 40 degrees Fahrenheit or below, and the freezer should be at 0 degrees Fahrenheit or below. 

During a power outage, the CDC recommends keeping refrigerator and freezer doors closed. If the doors are closed, the food will stay safe for up to four hours in the refrigerator, 48 hours in a full freezer and 24 hours in a half-full freezer. If the power has been out for four hours and a cooler and ice is available, then put refrigerated perishable foods in the cooler. Add ice or a cold source like frozen gel packs to keep the food at 40 degrees Fahrenheit or below.

After the power comes back on, here's what you should do to determine the safety of your food.

If you have an appliance thermometer, check the temperature. If the freezer is 40 degrees Fahrenheit or below, the food is safe and can be refrozen. 

If you don't have a thermometer, check each package of food to determine its safety, and don't rely on appearance or odor. If the food still contains ice crystals or is below 40 degrees Fahrenheit, it's safe to refreeze or cook.

More:There's a power outage, and you're hungry—what can you cook?

More:A heat wave is coming—these 9 products will help if you lose power

If power was out for more than four hours, food in the refrigerator should be safe as long as the doors were kept closed. One power comes back on, check the temperature and discard any perishable food (including meat, poultry, seafood, milk, eggs or leftovers) that has been above 40 degrees Fahrenheit for four hours or more. 

Perishable foods with temperatures that are 45 degrees Fahrenheit or below should be safe, but the CDC recommends they should be cooked and eaten as soon as possible. Perishable food that's not kept cold enough may cause illness if it's eaten, even when thoroughly cooked, so be extra careful with those kinds of foods. 

To help determine the safety of specific food items, use the power outage safety chart from FoodSafety.gov. 

There are also steps on what to do to get clean drinking water if it floods. Only use water from a safe source for drinking, washing or preparing food, and if it's available, use bottled water. 

If there's no bottled water, boil or disinfect water to make it safe. Here's how:

If the water is cloudy, first filter it through clean cloths, or allow it to settle and draw off the clean water for boiling and disinfecting. 

As for food, the U.S. Food and Drug Administration says to not eat any food that might have come in contact with flood water, and discard any food and beverage not in a waterproof container, if there's any chance it came into contact with flood water.

Discard any food in damaged cans, thoroughly wash metal pans, ceramic dishes and utensils and thoroughly wash countertops.