How is the Wind Chill is calculated?
The wind chill temperature is calculated using the following formula:
Wind Chill (°F) = 35.74 + 0.6215T - 35.75(V0.16) + 0.4275T(V0.16)
Where: T = Air Temperature (F)
V = Wind Speed (mph)
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Wind
Chill Terms and Definitions
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- What is Wind Chill Temperature?
- Can Wind Chill Impact my car's radiator or exposed water
pipe?
- What is Frostbite?
- What is Hypothermia?
- Tips on how to dress during cold weather
- Avoid overexertion
- Is there a Celcius version of the Wind Chill Calculator?
- Wind Chill factor vs. wind chill temperature
- Is it possible to get frostbite if the temperature
is above freezing?
- How is the Wind Chill is calculated?
- When does the NWS issue a Wind Chill Advisory or Warning?
- Does windchill only apply to people and animals?
- Does humidity or being near a large water body affect
on wind chill?
- How does this chart apply to children?
1. What is wind chill temperature? back
A. The wind chill temperature is how cold people and animals feel when
outside. Wind chill is based on the rate of heat loss from exposed skin
caused by wind and cold. As the wind increases, it draws heat from the body,
driving down skin temperature and eventually the internal body temperature.
Therefore, the wind makes it FEEL much colder. If the temperature is 0 degrees
Fahrenheit and the wind is blowing at 15 mph, the wind chill is -19 degrees
Fahrenheit. At this wind chill temperature, exposed skin can freeze in 30
minutes.
2. Can wind chill impact my car's radiator or exposed
water pipe? back
A. The only effect wind chill has on inanimate objects, such
as car radiators and water pipes, is to shorten the amount of time for the
object to cool. The inanimate object will not cool below the actual air
temperature. For example, if the temperature outside is -5 degrees Fahrenheit
and the wind chill temperature is -31 degrees Fahrenheit, then your car's
radiator will not drop lower than -5 degrees Fahrenheit.
3. What is FROSTBITE? back
A. You have frostbite when your body tissue freezes. The most
susceptible parts of the body are fingers, toes, ear lobes, or the tip of
the nose. Symptoms include a loss of feeling in the extremity and a white
or pale appearance. Get Medical attention immediately for frostbite. The
area should be SLOWLY re-warmed.
4. What is HYPOTHERMIA? back
A. Hypothermia occurs when body temperature falls below 95 degrees Fahrenheit.
Determine this by taking your temperature. Warning signs include uncontrollable
shivering, memory loss, disorientation, incoherence, slurred speech, drowsiness,
and exhaustion. Get medical attention immediately. If you can't get
help quickly, begin warming the body SLOWLY. Warm the body core first,
NOT the extremities. Warming extremities first drives the cold blood
to the heart and can cause the body temperature to drop further--which may
lead to heart failure. Get the person into dry clothing and wrap in a warm
blanket covering the head and neck. Do not give the person alcohol, drugs,
coffee, or any HOT beverage or food. WARM broth and food is better. About
20% of cold related deaths occur in the home. Young children under the age
of two and the elderly, those more than 60 years of age, are most susceptible
to hypothermia. Hypothermia can set in over a period of time. Keep the thermostat
above 69 degrees Fahrenheit, wear warm clothing, eat food for warmth, and
drink plenty of water (or fluids other than alcohol) to keep hydrated. NOTE:
Alcohol will lower your body temperature.
5. Tips on How to Dress during cold weather back
A. The best way to avoid hypothermia and frostbite is to stay warm and
dry indoors. When you must go outside, dress appropriately. Wear several
layers of loose-fitting, lightweight, warm clothing. Trapped air between
the layers will insulate you. Remove layers to avoid sweating and subsequent
chill. Outer garments should be tightly woven, water repellent, and hooded.
Wear a hat, because half of your body heat can be lost from your head. Cover
your mouth to protect your lungs from extreme cold. Mittens, snug at the
wrist, are better than gloves. Try to stay dry and out of the wind.
6. Avoid Overexertion back
A. Your heart is already working overtime in cold weather. The
strain from the cold and the hard labor of shoveling heavy snow, walking
through drifts or pushing a car may cause a heart attack. Sweating from
overexertion could lead to a chill and hypothermia.
7. Is there a Celsius version of the
chart? back
A. We will look into adding a Celcius version to the web page
calculator. In the mean time, you can go to http://www.wrh.noaa.gov/Monterey/convert.html#celsius
8. Wind chill factor vs. wind chill temperature. back
A. These terms are almost the same. The wind chill factor describes
what happens to a body when it is cold and windy outside. As wind increases,
heat is carried away from the body at a faster rate, driving down both
skin temperature (which can cause frostbite) and eventually the internal
body temperature (which can kill).
Wind chill temperature is a unit of measurement to describe the wind
chill factor. Wind chill temperature is a measure of the combined cooling
effect of wind and temperature. Since you and your husband ride motorcycles,
you can insert your driving speed to estimate the wind speed and the outside
temperature. These two parameters combined will give you the wind chill
temeprature, or how it feels to you skin. On the bottom of the wind chill
chart is the updated wind chill temperature formula.
9. Is it possible to get frostbite if the temperature
is above freezing but the windchill is below freezing? back
The air temperature has to be BELOW freezing in order for frostbite to
develop on exposed skin.
10. How is the Wind Chill is calculated? back
The wind chill temperature is calculated using the following formula:
Wind Chill (ºF) = 35.74 + 0.6215T - 35.75(V^0.16) + 0.4275T(V^0.16)
Where: T = Air Temperature (F)
V = Wind Speed (mph)
^ = raised to a power (exponential)
11. When does the National Weather Service issue
a Wind Chill Advisory or Warning? back
Criteria for issuing Wind Chill Warnings and Advisories are set locally.
For the Rochester, NY area, Wind Chill Warnings are issued when the Wind
Chill Temperature is expected to fall at or below -25 F. Wind Chill Advisories
are issued when the wind chill temperature is expected to fall between
-15F and -24F.
12. Does windchill only apply to people and animals? back
Yes. The only effect wind chill has on inanimate objects, such as car
radiators and water pipes, is to more quickly cool the object to cool
to the current air temperature. Object will NOT cool below the actual
air temperature. For example, if the temperature outside is -5 degrees
Fahrenheit and the wind chill temperature is -31 degrees Fahrenheit, then
your car's radiator will not drop lower than -5 degrees F.
13. Does humidity or being near a large water body
affect on wind chill? back
When we tested the new Wind Chill Temperature Index (WCTI), our researchers
applied the new index to 12 test subjects. The results of the tests showed
that relative humidity was an insignificant weather parameter, less than
one degree at worst. To simplify the calculation, relative humidity was
left out of the formula.
We did research a wet wind chill or blowing water spray. This research
was to simulate a person near a body of water or a mariner. These findings
are being finalized and may be incorporated for the winter season 2003-2004.
14. How does this chart apply to children? back
The tests that were done on Wind Chill were conducted on adult subjects.
For legal and safety reasons, NWS could not ask for child volunteers.
Use the existing chart as a starting point and be even more cautious with
children, seniors and persons with compromised health.
Information on cold-related
health problems and outdoor
safety from the Centers for Disease Control and Prevention (CDC)
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