Winter storm preparedness

Most hypothermia deaths happen inside

CDC defines hypothermia as a core body temperature below 95°F. The popular image of hypothermia involves someone stranded outdoors in a blizzard. The reality in U.S. mortality data is different: a substantial proportion of hypothermia deaths occur indoors, in homes that have lost heat during extended winter power outages.

Elderly adults are disproportionately affected. The reasons are physiological: older adults have reduced muscle mass (which generates heat), impaired vasoconstriction (the narrowing of blood vessels that reduces heat loss from the skin), reduced shivering response, and lower baseline metabolic rate. They also often have chronic conditions and take medications that further impair temperature regulation.

The classic early warning sign: the person says they feel fine. This is not reassurance — it is a symptom. As core temperature drops toward the hypothermic range, people often lose the ability to accurately assess their own condition and may report feeling comfortable or even warm. Confusion, slowed speech, and reduced coordination follow.

When indoor temperatures drop below 60°F and vulnerable people are present, treat the situation as a medical concern, not a comfort issue. Wrap the person in blankets, concentrate heat in one room (using safe heat sources), provide warm non-alcoholic beverages if the person is conscious and alert, and monitor continuously. If confusion or altered consciousness is present, call 911. Hypothermia is a medical emergency.

What works. What kills.

When the power goes out in winter, the instinct is to find a heat source. The choices people make at this point are the primary driver of winter-outage carbon monoxide deaths.

Never use indoors: gas camping stoves, charcoal grills, propane heaters not designed for indoor use, portable gasoline generators, charcoal or wood burning in unapproved appliances, or any combustion device not designed and ventilated for enclosed spaces. These produce carbon monoxide. CO is colorless and odorless. You will not smell it or see it. You will lose consciousness without warning and die without calling for help.

Safe heat sources during outages: electric space heaters powered by a properly placed outdoor generator (through a heavy-duty extension cord), a fireplace or wood stove that vents to the exterior (if your home has one and the flue is clear), or supplemental layering — more clothing, sleeping bags rated for cold temperatures, and concentrating the household in one small room to preserve body heat collectively.

Keeping the home's CO alarm batteries fresh is the other half of this equation. CPSC recommends battery-operated CO alarms on every level. During an outage, your hardwired alarms may not work. A battery-backup CO alarm is the last line of detection if someone makes a dangerous fuel choice.

The car is your shelter. Stay with it.

Ready.gov, the Red Cross, and winter driving safety authorities consistently give the same advice: if you are stranded in a vehicle during a winter storm, stay with the vehicle. A car is visible to search and rescue. Walking in whiteout conditions without knowing your precise location is how people freeze to death within yards of the road.

What to do while waiting: run the engine 10 minutes per hour for heat, not continuously. Before running the engine, clear the exhaust pipe of accumulated snow — a blocked exhaust pipe channels CO directly into the cabin. Keep a window cracked slightly on the side away from wind to allow fresh air. Turn on the car's hazard lights. Tie a brightly colored cloth to the antenna or place it in a window. Stay awake by moving your arms and legs.

Winter vehicle kit contents: a wool or synthetic blanket or sleeping bag, water and energy bars, a flashlight with fresh batteries, a bright cloth or road flares for signaling, a small shovel, sand or kitty litter (for traction under the tires), jumper cables or a jump-start pack, a first aid kit, and a phone charger. These items cost less than $75 and live in the trunk year-round in cold climates.

An empty pipe cannot burst

Pipes burst when water freezes inside them: water expands about 9% when it turns to ice, and the pressure that builds in a sealed pipe can crack copper, break PVC, and split steel. The resulting water damage, once temperatures rise and the ice thaws, is typically extensive and expensive.

For brief, moderate freezes (temperatures above 15°F, heat loss partial): open cabinet doors under sinks along exterior walls, let all faucets drip slightly to keep water moving, and insulate exposed pipes in unheated spaces with foam pipe insulation.

For extended, severe freezes (sustained temperatures below 10–15°F, or total heat loss): the dripping-faucet method is insufficient. Shut off the main water supply at the meter or main shutoff valve and open all faucets to drain the system. An empty pipe cannot burst. Know where your main shutoff valve is before this situation arises — it is typically near where the water line enters the home, in the basement, crawlspace, or a utility area near the front of the house.

If pipes freeze before you can act, do not use an open flame to thaw them — this is a fire risk. Use a hair dryer, electric heat tape, or warm towels applied directly to the pipe, working from the faucet end toward the frozen section. If you cannot locate the frozen section or the pipe has already burst, shut off the water main and call a plumber.

Act before the storm, not during it

Households with members who depend on electrically powered medical equipment — oxygen concentrators, ventilators, infusion pumps, CPAP machines, refrigerated medications — face a narrower decision window before a major winter storm than other households.

Once a multi-day power outage is forecast, the clock is running. Gas stations and pharmacies begin closing. Roads become dangerous. Deliveries of backup equipment stop. The window between "we should move the person" and "we cannot safely move the person" can close in less than 12 hours.

Action steps 48 hours before a major storm: contact the medical equipment supplier to confirm backup equipment (cylinders, battery packs) and arrange delivery if needed. Notify the electric utility — most maintain a medical priority list for customers dependent on life-support equipment. Evaluate whether the person should relocate to a location with reliable power: a hospital, a hotel with a generator, a family member's home outside the forecast area.

The American Lung Association recommends that all oxygen-dependent patients and their families develop an outage plan before storm season, not during individual storms. The plan should include the supplier's emergency number, the nearest hospital address, and a contact outside the area who can assist with coordination.

What to verify before driving after extended cold exposure

Cold temperatures reduce tire pressure approximately 1 PSI per 10°F drop below the inflation temperature. A vehicle that has sat in sustained below-freezing temperatures may have tires significantly underinflated, affecting handling and braking distance. Brake rotors can also develop surface rust that requires low-speed testing before highway use. Check tire pressure before any post-cold-snap drive; visually inspect tires for sidewall cracking if the vehicle has been stationary for an extended period. Ready.gov's vehicle preparedness guidance includes maintaining tire pressure as a year-round safety habit.