Winter Weather Preparedness Week for Virginia  November 28 - December 2nd, 2022

Monday

Winter Season Outlook and winter weather terminology

This will provide you with some terms the National Weather Service uses to describe winter weather as well as the definitions of watches, warnings, and advisories issued for winter weather events.

 

temperature outlook

 

precipitation forecast

 

Watches are issued when a storm is in it's early stage of development, and may create conditions that may harm life and property. Hazardous winter weather is only a possibility, not a certainty. 

The following are the watch headlines issued for winter weather events: 

  • Winter Storm Watch is issued when heavy snow, damaging ice accumulations, or blizzard conditions are possible. Winter storm watches are typically issued 24 to 48 hours before a winter storm starts.  Watches are issued when at least 3 inches of snow, and/or 1/4 inch or more of ice accumulation is expected in a 12 to 24 hour period. 
  • Wind Chill Watch is issued when dangerously cold wind chills are possible typically in the next 12 to 48 hours. 

 

Warnings are issued when the threat to life and property is imminent or has already begun from severe winter weather.

The following are the warning headlines issued for winter weather events:

  • Winter Storm Warning is issued when hazardous winter weather in the form of heavy snow, freezing rain, sleet or any combination there of, is imminent or occurring. Winter storm warnings are typically issued 12 to 36 hours before the event is expected to start.
  • Ice Storm Warning is issued when damaging ice accumulations are expected within the next 12 to 36 hours.
  • Blizzard Warning is issued when sustained or gusty winds of 35 mph or more prevail, combined with falling or blowing snow, visibility of one quarter of a mile or less, and last for at least 3 hours.
  • Snow Squall Warning is issued for short duration intense bursts of snow and wind leading to whiteout visibility and possible flash freezes on roads.
  • Wind Chill Warning is issued when the combination of extreme cold and winds occur. This combination will result in frostbite, hypothermia, or even death when exposed in this type of condition for an extended period of time.  These are issued when wind chill values are expected to be less than -15F.  

 

Advisories are issued for less serious weather conditions that will not cause immediate threat to life and property. Advisories will be issued when weather conditions will impact motorists, outdoor activities, or public events. These events could become life-threatening if proper precautions are not taken.

The following are the advisory headlines issued for winter weather events:

  • Winter Weather Advisory is issued for accumulations of snow, lake effect snow, freezing rain, freezing drizzle, or sleet, that will create inconveniences. During an advisory, if caution is not exercised, life and property may be threatened.  Snow of a coasting to less than 3" and any amount of ice accretion. 
  • Wind Chill Advisory is issued when wind chill temperatures create inconvenience to life with prolonged exposure. If caution is not exercised, hypothermia and frostbite may occur.  Issued for wind chills values less than 0 degree but not colder than -14F.  

 

Winter infographics