The signs of hypothermia are the changes a body shows when it loses heat faster than it can make it, and knowing them lets you catch the problem while it is still easy to fix. We define hypothermia as a core body temperature below 95 degrees F. In a cold house during a winter power outage, it can settle in quietly on a family member who is sitting still under one thin blanket. Babies and older people are often the first to get cold and the last to say so.
You may be reading with the lights still on, planning ahead for storm season. You may also be reading by flashlight with the heat out and the house cooling. Either way, the skills are the same. They fit the first three days of an outage, when most families shelter at home and wait for crews to restore power.
Start by walking through your home and naming who would feel the cold first. Think of the baby, the grandparent, the person on daily medicine, and the dog asleep on the cold kitchen tile. Those are the people and pets you will check most often, and the rest of the plan builds around them.
Reading the Signs of Hypothermia, Stage by Stage
Knowing the stages lets you act at the shivering stage, when a blanket and a warm drink still fix things. The early signs can be treated at home. The later signs need 911. Learn both, along with the reasons cold can catch you indoors, and then you will be ready to look at who is most at risk.
The First Signs
- Shivering. Shivering is the body making heat by working its muscles, and it is your first signal to act.
- Numb hands. Blood pulls back from the fingers to protect the heart and brain, so hands go stiff and clumsy.
- Slurred speech. Words come out slow or thick, as if the person is very tired.
- Fumbling. Zippers, buttons, and phone screens suddenly become hard to work.
- Poor judgment. A cold person may take off a coat, wander outside, or insist that nothing is wrong.
The Umbles
The umbles are a simple memory aid for the early signs of hypothermia. Watch for stumbles, mumbles, fumbles, and grumbles. Stumbles are clumsy steps and lost balance. Mumbles are slurred or very quiet speech. Fumbles are dropped cups and trouble with buttons. Grumbles are a sudden change in mood, often cranky or flat. One umble is your cue to warm the person now. Two or more mean you stay close and keep watching while you warm them.
The Danger Signs
Severe hypothermia often looks calmer than the early stage, which is why families miss it. Call 911 if you see any of these.
- Shivering stops. A very cold person who stops shivering without warming up has run out of the ability to make heat.
- Drowsiness. The person is hard to wake, drifts off mid-sentence, or seems confused.
- Slow breathing. Breaths become shallow and far apart.
- Weak pulse. The pulse at the wrist or neck is faint, slow, or hard to find.
Wet Clothes and Wind
It is fair to picture hypothermia on a frozen mountain, since freezing air is a real cause. The body also loses heat in much milder weather. Water pulls heat from skin far faster than air does, so a sweat-damp shirt after shoveling snow keeps drawing heat away. Wind strips off the thin layer of warm air next to your skin, which is what wind chill measures. Hypothermia can set in well above 40 degrees F when someone is wet or exposed to wind. Indoors, an older adult who sits still for hours in a house in the low 60s can slowly lose core heat too.
Who Feels the Cold First
Knowing who is most at risk tells you where to look first when the heat goes out. Some family members lose heat faster than others, and some cannot tell you they are cold. Once you know who they are, the first aid steps that follow will make more sense.
A winter power outage turns any of these risks into a real Threat. Without a furnace, a house can drop into the 50s within a day or two in hard cold. Your goal is to spot the slide early, before anyone reaches the danger signs.
Babies
Babies lose heat fast because they have a lot of skin for their small size. They also cannot shiver well to make heat. The signs of hypothermia in a baby look different from an adult's: bright red, cold skin and very low energy. A baby who feels cold on the chest, feeds poorly, or is unusually quiet needs warming and a call to the doctor. Check the chest or the back of the neck, because hands and feet are often cool even in a warm baby. Dress the baby in one more layer than you are wearing. For sleep, use a wearable blanket or sleep sack and keep loose blankets out of the crib, so the baby stays warm and the sleep space stays safe.
Older Adults in Cold Homes
Older adults make less body heat, shiver less, and may not feel cold the way they once did. Many live alone, and many cases of hypothermia in older people happen indoors. Picture a grandparent who says they are fine while sitting under one blanket in a 58 degree living room. Feel the skin on the belly or chest, not just the hands. Ask a few simple questions, such as the day of the week. Slow answers, confusion, or a flat mood are early signs of hypothermia worth acting on.
Medicines, Diabetes, and Drinking
Some health conditions and medicines change how the body controls temperature. Diabetes can reduce blood flow and feeling in the hands and feet, so cold goes unnoticed. Low blood sugar also leaves the body with less fuel to make heat, so keep regular meals and snacks going during an outage. Some medicines for blood pressure, mood, sleep, and anxiety can affect temperature control or alertness. Ask your pharmacist now which family medicines do, and write the answer on your emergency card. Alcohol widens blood vessels near the skin, so a drink feels warming while the body actually loses heat faster. It also dulls judgment, so a person who has been drinking may skip the coat or doze off in a cold chair.
Dogs and Cats
Pets get hypothermia too, and small, short-haired, very young, and older animals lose heat fastest. The signs of hypothermia in dogs and cats include shivering, weakness, slow movement, curling up tightly, cold ears and paws, pale gums, and slow breathing. A pet that stops shivering, seems confused, or is hard to wake needs a call to your vet right away. Wrap the pet in a dry blanket and bring the bed into your warm room. A dog first-aid kit with a digital thermometer helps you check rather than guess.
More People, More Heat
A home with a baby, a grandparent, and a dog has more people to watch. It also has more bodies sharing heat in one small room. A full house is more mouths and also more warmth, and everyone can keep an eye on everyone else.
First Aid: Warm the Core, Gently
Safe first aid brings body heat back without straining a cold heart. The order matters, because the core needs heat before the arms and legs do. Work through the steps below, then read the short note on frostbite, which often shows up alongside hypothermia.
- Call 911 for severe signs. If shivering has stopped, or the person is drowsy, confused, breathing slowly, or has a weak pulse, call first. Start the next steps while you wait, and follow the dispatcher's instructions, including CPR if the person stops breathing.
- Move them somewhere warm. Bring the person into your warmest room, out of the wind and off a cold floor. If they are very cold, help them lie down rather than walk.
- Remove wet clothing. Take off damp clothes, and cut them off if that avoids rough handling. Replace them with dry layers and cover the head and neck.
- Warm the core first. Wrap the chest, neck, head, and groin in dry blankets, a sleeping bag, or towels. Skin-to-skin contact works well: you can lie close to the person under loose blankets and share your body heat. Warm, not hot, water bottles wrapped in a towel and placed on the chest, neck, and groin add more heat.
- Give warm, sweet drinks only if they are alert. If the person is fully awake and can swallow easily, offer warm juice or sweet cocoa. The sugar gives the body fuel to make its own heat. If they are drowsy or confused, give nothing by mouth, because they could choke.
- Keep them wrapped and watched. Once the person warms up, keep them dry, covered, and resting. Get medical care for anyone who had severe signs, even if they seem fine now.
Handle Gently
A very cold heart is easily upset. Rough moving, jolting, or making a severely cold person walk can trigger a dangerous heart rhythm. Lift slowly, keep them lying flat, and move them as little as you can. Think of carrying a full pot of soup, not a sack of laundry.
Keep Warming Slow and Central
- Leave the arms and legs still. Rubbing or massaging the limbs can send cold blood back to the heart too fast and can damage cold skin, so keep your effort on the trunk.
- Choose blankets over a hot bath. A hot bath or shower warms the skin too fast, can drop blood pressure, and can strain the heart, while blankets and body heat warm steadily and safely.
- Serve cocoa or juice instead of alcohol. Alcohol speeds heat loss and dulls the signs you are watching, while a warm sweet drink gives real fuel.
A Note on Frostbite
Frostbite is the freezing of skin and the tissue under it, most often on fingers, toes, ears, nose, and cheeks. It often travels with hypothermia, and hypothermia gets treated first because it affects the whole body. Watch for skin that turns white or grayish-yellow, feels firm or waxy, and goes numb. Keep the area still and protected, and warm it only when it will not refreeze. Our page on frostbite symptoms walks through each stage and how to care for it.
Prevent It at Home and Outdoors
Prevention keeps the first aid steps on the shelf where they belong. Simple habits keep the whole family warm through an outage. They also make the signs of hypothermia easier to catch, because you are already checking on each other. Use them to build a plan you can start this weekend.
Layers Indoors
Dress in layers inside, the same way you would for a walk outside. A wool or synthetic base layer pulls sweat away from skin. A fleece or wool middle layer holds heat. A hat, thick wool socks, and slippers keep heat from leaking out at the edges. Choose wool over cotton, because cotton holds moisture against skin. Several loose layers trap more warm air than one tight sweater. If someone starts to sweat, take a layer off before the sweat soaks in, then add it back once they cool down.
One Warm Room
Pick one room to heat and live in during an outage. Choose a small interior room with few windows, close the doors, and roll towels against the gaps. Hang blankets over windows and doorways, and lay rugs on bare floors. If you have a fireplace or wood stove, make that room your warm room. If you have only blankets and body heat, choose the smallest room, because it warms fastest and every person inside adds heat. Run any generator outdoors, far from windows and doors, and keep a battery carbon monoxide alarm in the warm room so the heat you add stays safe. Keep food and warm drinks coming, since a fed body makes more heat.
Moisture
Keep everyone dry, both indoors and out. Change wet socks and gloves right after outdoor chores. Swap a damp shirt for a dry one as soon as you come in from shoveling. Outdoors, wear a windproof outer layer and cover your head, neck, and hands. Hang wet gear near the warm room door to dry, away from where people sleep.
Neighbors Living Alone
Check on older neighbors twice a day, once in the morning and once in the evening. Knock, ask how warm the house feels, and watch for the umbles while you talk. Preppers know that a short list of names and a set time works better than good intentions. Trade phone numbers before the storm and agree on who checks on whom. If a neighbor's home is too cold, offer a spot in your warm room or help them reach a warming center.
Start This Weekend
- Choose your warm room. Pick the room, gather the window blankets and door towels, and store them in one bin inside it.
- Lay in layers for everyone. Put by a wool hat, wool socks, and an extra blanket for each person, plus a dry bed for each pet.
- Write your check-in list. List the family members and neighbors at highest risk, their medicines, and the times you will check on them.
For the rest of your winter storm preparedness, from food and water to safe heat and travel, see our full plan, How to Prepare for a Winter Storm. We share general information here, not medical advice. For any health question, call your doctor, and for severe signs, call 911.
