What is wind chill?
Wind chill describes the increased rate of heat loss from exposed skin during cold, windy weather. Wind removes the thin layer of warmed air next to the body, making the same air temperature feel colder as wind speed rises.
When the formula applies
The National Weather Service defines wind chill for air temperatures at or below 50°F (10°C) and wind speeds above 3 mph (4.8 km/h). Outside that range, this calculator reports that the standard wind chill formula does not apply instead of presenting a misleading number.
The calculation assumes no warming from sunshine. Bright sun can make the apparent temperature feel 10–18°F warmer, while wet clothing and exposed locations can increase heat loss.
Cold-weather safety
Very low wind chill can cause frostbite on exposed skin. Cover your face and hands, wear dry layers and use official local warnings when planning time outdoors. Wind chill is an estimate for people and animals; it does not make an inanimate object colder than the actual air temperature.
Frequently asked questions
Can wind chill freeze water above 32°F?
No. Wind can cool an object toward the actual air temperature faster, but cannot cool it below the air temperature.
Does sunshine affect wind chill?
Yes. The standard formula assumes no solar warming; bright sunshine can make conditions feel warmer.
Why is there no wind chill result in mild weather?
The official formula is defined only at or below 50°F with wind above 3 mph. Outside that range, air temperature is the more useful value.
Method and sources
Last reviewed: July 11, 2026.
