v Blizzard Warning: Issued for sustained wind speeds or frequent gusts of 35 M.P.H. or more and falling or blowing snow which reduces visibility to less than ¼ of a mile for at least three hours.
v Freezing Rain: Rain that falls onto a surface with a temperature below freezing. This causes it to freeze on contact with these surfaces. An ice coating or glaze can form on trees, cars and roads. Even small amounts can become a significant hazard.
v Frostbite: Damage to body tissue cause by tissue being frozen. Frostbite causes the loss of feeling and a white or pale appearance in the extremities such as fingers, toes, ear lobes or the tip of the nose. If symptoms are detected, slowly warm the affected area(s) and seek medical help immediately.
v Hypothermia: The loss of heat from the body. Warning signs are uncontrollable shivering, memory loss and distortion. Medical treatment should be sought immediately.
v Sleet: Rain drops that freeze into ice pellets. These are transparent or translucent pellets of ice of 5 millimeters or less in diameter before reaching the ground. Sleet usually bounces when hitting a surface and does not stick to objects. However, it can accumulate like snow and cause a hazard to motorists and pedestrians.
v Snow Flurries: Intermittent light snowfall of short duration. Usually causes no accumulations.
v Snow Showers: Brief periods of snowfall in which intensity can be varied and may change rapidly. Some accumulation is possible.
v Snow Squalls: Brief, intense snow showers accompanied by strong, gusty wind. Accumulation may be significant.
v Wind Chill: Based on the rate of heat loss from exposed skin. It is caused by the combined effects of wind and cold temperatures. As the wind increases, heat is carried away from the body at an accelerated rate, driving down the body temperature. Animals are also affected by wind chill. Inanimate objects such as pipes and car radiators are not affected. So a wind chill below freezing, with a real temperature above freezing will not cause pipes to freeze. Wind chill at -20° can cause frostbite in 15 minutes or less.
v Winter Storm Watch: Winter events are expected in the next 12 to 48 hours. This is issued when the following is forecasted to occur:
§ Snow-Accumulations of 2 inches or more
§ Freezing Rain-Ice accumulations of ¼ of an inch or more
§ Sleet-Accumulation of one inch or more
§ Wind Chill-At or below -10°
v Winter Storm Warning: Issued when hazardous winter weather is occurring, is imminent, or has a high probability of occurrence within the next 0 to 36 hours. If forecasters’ confidence in a predominant precipitation type is high, the warning can be event specific such as a heavy snow warning, sleet warning, and ice storm warning. This is issued when the following is occurring or is forecasted to occur:
§ Snow-Accumulations of 2 inches or more
§ Freezing Rain-Ice accumulations of ¼ of an inch or more
§ Sleet-Accumulation of one inch or more
§ Wind Chill-At or below -10°
v Winter Weather Advisory: Issued for winter events that are significant to the public, but does not constitute a serious enough threat to life and property to warrant the issuance of a warning. These advisories are issued for forecasted accumulations less than those of the winter storm warning.
Source: National Weather Service in Birmingham: Winter Weather Terminology. Found at http://www.srh.noaa.gov/bmx/index.php?n=winteraware2009pnsday2
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