On Sunday at 3:54 p.m. an extreme cold warning was issued by the National Weather Service valid from 9 p.m. until Monday noon for Marshall, Jackson, DeKalb and Cullman counties.

The weather service describes, “Dangerously cold wind chills below minus 5 expected.”

“Frostbite and hypothermia will occur if unprotected skin is exposed to these temperatures. An extended period of subfreezing temperatures could cause pipes to burst,” describes the weather service. “Dress in layers including a hat, face mask, and gloves if you must go outside. To prevent water pipes from freezing; wrap or drain or allow them to drip slowly. Make sure outdoor animals have a warm, dry shelter, food, and unfrozen water. Make frequent checks on older family, friends, and neighbors. Ensure portable heaters are used correctly. Do not use generators or grills inside.”

Understanding cold weather alerts

Extreme cold warning: Take Action! An extreme cold warning is issued when dangerously cold air temperatures or wind chill values are expected or occurring. If you are in an area with an extreme cold warning, avoid going outside. If you have to go outside, dress in layers, cover exposed skin, and make sure at least one other person knows your whereabouts. Update them when you arrive safely at your destination.

Extreme cold watch: Be Prepared. An extreme cold watch is issued when dangerously cold air temperatures or wind chill values are possible. As with a warning, adjust your plans to avoid being outside during the coldest parts of the day. Make sure your car has at least half a tank of gas, and update your winter survival kit.

Cold weather advisory: Be Aware. A cold weather advisory is issued when seasonably cold air temperatures or wind chill values, but not extremely cold values, are expected or occurring. Be sure you and your loved ones dress appropriately and cover exposed skin when venturing outdoors.

Advance Local Weather Alerts is a service provided by United Robots, which uses machine learning to compile the latest data from the National Weather Service.