Warnings are generally issued up to 24 hours before the expected start of events. Watches are generally issued 12 to 36 hours before the expected start of events. OR if wind gusts from 46 to 57 MPH are forecast for any duration. Wind Chill Advisory - Issued by the National Weather Service when the wind chill values are forecast 20 to 34 degrees below zero. When the combination of wind speed and air temperature produce these wind chill values, exposed skin would gradually suffer frostbite within a relatively short period of time.
Protective action is recommended.
Wind Chill Factor - The apparent temperature which describes the cooling effect on exposed skin by the combination of temperature and wind, expressed as the loss of body heat. Increased wind speed will accelerate the loss of body heat. When the combination of wind speed and air temperature produce these wind chill values, exposed skin would suffer frostbite within a short period of time. Immediate protective action is required. A combination of heavy snow and ice.