National Weather Service United States Department of Commerce

Snow Across the Great Lakes, Central Appalachians, and Northeast; Unsettled Weather in the West

Light to moderate snow will continue into Saturday over the Great Lakes, Central Appalachians, and Northeast. This weekend into next week, a series of atmospheric rivers will bring gusty winds, periods of heavy rain, and mountain snow to northern California and the Pacific Northwest. Colder temperatures are in store for the weekend from the Great Lakes to East Coast. Read More >

Wyoming Winter Weather Awareness Day

NWS Winter Weather Terminology

Early Season Winter Storm
An early season snow storm knocked several tree branches down in Riverton, occuring in late September of 2013, showing the importance of monitoring the latest Winter Weather Watches, Warnings, and Advisories.

Overview Terminology Home/Outdoor Safety Driving Safety Road Conditions Weather Sources Social Media

Understanding and Staying Aware of the Weather

  • Outlook: Winter Storm conditions are possible in the next 2-5 days. The Outlook information can be found in the Hazardous Weather Outlooks produced by:
    Riverton | Cheyenne | Billings | Rapid City | Salt Lake City

  • Watch: Winter storm conditions are possible within the next 36-48 hours. Prepare now!

  • Warning: Life-threatening severe winter conditions have begun or will begin within 24 hours. Act now!
      
  • Advisory: Winter weather conditions are expected to cause significant inconveniences and may be hazardous. If you are cautious, these situations should not be life threatening.
      
  • Blizzard: Winds of 35 mph or more with snow and blowing snow reducing visibility to less than 1/4 mile for at least 3 hours.
      
  • Blowing Snow: Wind driven snow that reduces visibility. Blowing snow may be falling snow and/or snow on the ground picked up by the wind.
      
  • Snow Squalls: Brief, intense snow showers accompanied by strong, gusty winds. Accumulation may be significant.
      
  • Snow Showers: Snow falling at varying intensities for brief periods of time. Some accumulation is possible.
      
  • Snow Flurries: Light snow falling for short durations with little or no accumulation.
      
  • Ice Jams: Long cold spells can cause rivers and lakes to freeze. A rise in the water level or a thaw breaks the ice into large chunks which become jammed at man made and natural obstructions. Ice jams can act as a dam, resulting in severe flooding.
      
  • Snow Melt: Sudden thaw of a heavy snow pack often leads to flooding.
      
  • Wind Chill: Not the actual temperature but rather how wind and cold feel on exposed skin. 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; however, cars, plants and other objects are not. Find the current wind chill chart here.

  • Frostbite: Damage to body tissue caused by extreme cold. A wind chill of -20 degrees Fahrenheit (F) will cause frostbite in just 30 minutes. Frostbite causes a loss of feeling and a white or pale appearance in extremities, such as fingers, toes, ear lobes or the tip of the nose. If symptoms are detected, get medical help immediately! If you must wait for help, slowly rewarm affected areas. However, if the person is also showing signs of hypothermia, warm the body core before the extremes.
     
  • Hypothermia: A condition brought on when the body temperature drops to less than 95 degrees F. It can kill. For those who survive, there are likely to be lasting kidney, liver and pancreas problems. Warning signs include uncontrollable shivering, memory loss, disorientation, incoherence, slurred speech, drowsiness and apparent exhaustion. Take the person's temperature. If below 95 degrees F, seek medical care immediately.

    Please feel free to print this image and keep it somewhere to remember the differences between Watches, Warnings, Advisories and Outlooks:
    Watch, Warning, Advisories and Outlooks