Can you get hypothermia when it's above freezing?

Air above freezing can't give you frostbite, but it can still give you hypothermia.¹ It's what happens when you lose heat faster than your body can make it, until your core temperature falls to 95°F (35°C) or lower.² Cold, wet conditions carry the greatest risk, in any season, and even above 40°F a chill from rain, sweat or cold water can be enough.²³

Wet and wind speed up that heat loss.² Wind draws heat from your skin and, over time, from deeper inside your body.¹ Wet clothing keeps cooling you as the water evaporates, and sweat works the same way.² After a hard climb, the damp layer against your skin chills you once you stop to rest.⁴ Sitting on cold ground drains warmth through direct contact.² Pack a windproof, waterproof shell and a dry change of clothes, and keep your warm layers dry, since they insulate better that way.⁴

In cold water, other dangers come before hypothermia does.⁵ The shock of falling in makes you gasp and breathe fast for the first minute or two, and a gasp at the wrong moment can make you inhale water.⁵ Within about 10 minutes, your arms and legs weaken until you can't swim or hold on.⁵ Hypothermia itself can take 30 minutes or more in an adult without a wetsuit or drysuit, and you only last that long if something keeps you afloat.⁵ Always wear your life jacket when you paddle, and dress for the water temperature, not the air.⁵ Hypothermia can occur in any water below 70°F, and temperatures that don't sound very cold can still be deadly.⁵⁶

Shivering is your body making heat, and on its own it can mean you're cold rather than hypothermic.² It keeps you warm only while you have fuel to burn and insulation to hold the heat, and a long, cold day uses up that fuel.³ Alcohol blunts shivering and clouds judgment.⁷ If you're shivering but thinking clearly, act now: get out of the wind and wet, change into dry clothes, sit on a pad, eat, and sip a warm, sweet drink.² If warm beverages aren't available, cold, sweet drinks are still useful for someone alert, shivering and able to swallow.² In fact, the sugar is more important than the drink's temperature.³ A hot drink without any sugar feels good, but a cold, sweet drink does more to fight hypothermia.⁸ Fumbling hands, slurred speech, confusion, memory loss or drowsiness mean hypothermia is taking hold, and so does shivering that stops while someone is still cold.² Get medical help right away.³ Cooling slows the brain, so the person affected may not notice.² Watch each other.