This guide is for anyone spending time outdoors in winter, and people looking after older relatives, kids or anyone who works or plays outside in the cold.
Hypothermia is a drop in body temperature that can sneak up on people, especially when they’re wet, tired or not dressed for the weather. Knowing the signs helps you act early.
What hypothermia is
The National Weather Service says hypothermia occurs when the body loses heat faster than it can produce it.2 When your body temperature sinks below 95°F, you have hypothermia, a serious health hazard.1
It doesn’t take a blizzard. The NWS notes hypothermia can occur in temperatures as warm as 60°F.1 Our advice: being wet, from rain, sweat or a fall into water, makes it much more likely.
Warning signs
The NWS says to see a doctor immediately or go to the nearest emergency room if your temperature is 95°F or less, you feel cold and sluggish, or you are having trouble thinking clearly.1
It also notes that older adults may not shiver effectively, so don’t count on shivering as a warning sign for them.1 Our advice: watch for confusion, clumsiness, slurred speech and unusual sleepiness in anyone who has been in the cold.
What to do
The NWS’s steps:1
- Get medical attention immediately.
- Move the person inside to a heated location.
- Warm the center of the body first.
- If the person is unconscious, give CPR.
Our advice while you wait for help: remove wet clothing, wrap the person in dry blankets and give warm, non-alcoholic drinks only if they’re fully awake.
Hypothermia vs. frostbite
| Hypothermia | Frostbite | |
|---|---|---|
| What it is | Body temperature below 95°F1 | Freezing of the skin and tissue underneath |
| Early signs | Feeling cold and sluggish, trouble thinking clearly1 | Redness or pain, then white or grayish-yellow skin that feels firm or waxy, and numbness1 |
| First step | Get medical attention and warm the core1 | Get indoors, and don’t rub or massage the area1 |
More in our frostbite guide.
Prevention checklist
- Dress in loose layers with a water-repellent outer layer; see how to dress for cold weather.
- Stay dry, and change out of wet clothes quickly.
- Check on older neighbors and relatives during cold snaps.
- Know the signs: cold and sluggish, or not thinking clearly.
Sources & method
How we researched this
- This is a research-based guide, not a hands-on product test.
- Every measurement and safety figure is attributed to the source it comes from. Where we give our own advice, we say so.
- We don’t rank or recommend specific products in this guide.
Sources
- During Extremely Cold Weather, National Weather Service (NOAA). Accessed Nov 9, 2026.
- Cold Weather Safety, National Weather Service (NOAA). Accessed Nov 9, 2026.
Review history
- Published Nov 9, 2026.