KEEP AN EYE ON THE WIND CHILL
Jan. 15, 2004 — With an arctic airmass spreading over much of the northeastern U.S., the NOAA National Weather Service reminds residents in those affected areas to keep an eye on the wind chill, as well as the outside temperatures.
At 9:00 a.m. EST, the wind chill ranged from minus 7 in Central Park, N.Y., (actual temperature of 10 degrees F) to minus 76 at Mt. Washington, N.H., (actual temperature of minus 11). Boston, Mass., was shivering with a minus 17 wind chill, Albany, N.Y., at minus 27, and Bangor, Maine., at minus 31.
Wind chill is the term used to describe the rate of heat loss on the human body resulting from the combined effect of low temperature and wind. As winds increase, heat is carried away from the body at a faster rate, driving down both the skin temperature and eventually the internal body temperature. The wind chill index combines the temperature and wind speed to let you know how cold the wind “feels” against your skin. While exposure to low wind chills can be life threatening to both humans and animals alike, the only impact that wind chill has on inanimate objects, such as vehicles, is that it shortens the time that it takes the object to cool to the actual air temperature (it cannot cool the object down below that temperature). (Click NOAA image for larger view of NOAA National Weather Service forecast office in Gray, Maine, taken March 17, 2000, during high winds and severe wind chills. The temperature was about 17 degrees with a wind speed of about 25 mph producing a wind chill of about minus 1 degree Fahrenheit. Please credit “NOAA.”)
During times of adverse cold weather, wind chill advisories and warnings are issued by the NOAA National Weather Service to alert the public of the impending threat. Criteria varies slightly to reflect local conditions, but in general, wind chill warnings are typically issued when the wind chill is 20 below zero or lower. During these weather conditions, exposed flesh can freeze in less than 30 minutes.
Here are some Preparedness Tips for the Remainder of the Week.
In 2001, the NOAA National Weather Service started using a new formula that includes specific wind chill threshold values showing frostbite danger at given periods of time. The new wind chill index takes into consideration the following.
will gradually worsen unless the overall rate of heat loss can be stopped.
The warning signs for hypothermia may start with shivering and shaking
and may end in death. Initially, as the body temperature starts to drop,
shivering begins. At the same time, the brain begins to reduce the amount
of blood that is circulated to the extremities of the body in order to
conserve heat for the vital organs near the body's central core. If the
central core of the body continues to cool, uncontrollable shaking, memory
loss, disorientation, incoherence, slurred speech, drowsiness and apparent
exhaustion may develop. These are all signs of a very serious situation.
If the body core temperature drops below 95 degrees Fahrenheit, just 4
degrees below normal, immediate care is needed, as the person will likely
become irrational. Once the body core temperature drops below 90 degrees,
the person loses muscle control,
If a person is suffering from hypothermia, it's critically important that the person be warmed properly. If warmed improperly, death may result. In a hypothermic person, cold blood is concentrated in the extremities. If these extremities are warmed too quickly, this cold blood will be released into the body's central core, possibly lowering the central core temperature to a fatal level. Use the following steps to raise the core temperature of a hypothermic person.
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