National Weather Service United States Department of Commerce


Do you publish school closings during winter storms?


Not at this time. The best resources for school closings would be from your local school district or local media sources.

Does the "Wind Chill Index" correctly indicate how cold it feels?


Not exactly. The Wind Chill Index (WCI) is designed to tell you how cold you should feel, based solely on the current wind speed and air temperature. For example, if the current temperature is -22 °F (-30 °C), and the wind speed is 35 mph (15.6 m/s or 56 km/h), the WCI is equivalent to -58 °F (-50 °C). This is supposed to be the equivalent of walking at 3 mph (1.3 m/s or 4.8 km/h) in calm air at the WCI temperature. Several variables that affect how you really feel were approximated and incorporated into the formula as constants. Such things as surface wind speeds that vary significantly from the official measurements (usually due to sheltering effects of trees and buildings), skin that is already cold, and wind-breaking effects of certain clothing articles can cause the "real" wind chill to differ from the WCI. Still, the WCI is a reasonable approximation. Note that the above discussion has been updated (Dec. 18, 2002) to describe the new WCI

What is the difference between the old and the new Wind Chill Indices?


Okay, so far, no one has actually asked us this question, but it seemed like a likely candidate for the FAQ when the change took place. The wind chill formula was revised in 2001 to attempt to make the Wind Chill Index (WCI) more representative of reality. The previous formula gave values that were generally considered to be too cold. For details, please see the NOAA article on this subject. Follow the link to the PDF chart to find the actual equation for computing the new index.

Does water freeze if the Wind Chill Index is below freezing?


No, not unless the actual air temperature is also below freezing.

What is the effect of wind chill on plants and animals?


It is different than the effects on humans. Until detailed research can be done, the exact effects are too complex to determine. Please also see the other answers to questions on wind chill in this section.

Where can I find the current wind chill temperature?


You can normally view the current wind chill equivalent temperature simply by going to any NWS home page (such as ours), and supplying a city, state (or Zip code) in the box in the upper left, and clicking "Go". If the temperature is 50 °F (10 °C) or colder, and there is at least a light breeze, the wind chill equivalent temperature should be listed. You can also see the wind chill values in Oklahoma on the Oklahoma Mesonet website.