Know Your Winter Weather Terminology

Watches, and warnings, and alerts, oh my! Winter weather terminology can be confusing, but it’s important to understand what these phrases mean so that you can take appropriate steps to keep your home, family, and pets safe. Here are some definitions to get you started. To learn more, visit the weather.gov website.  

A winter storm watch is issued when winter storm or blizzard conditions are possible within the next three days, but the timing, intensity, or occurrence may still be uncertain. Make sure everyone knows the emergency plan in case you’re not together when winter weather strikes. Also, make sure your emergency kits are ready to go, in case you get stranded at home, work or on the road, or the power goes out. 

A winter storm warning means heavy snow is occurring or will develop in the next 36 hours. Heavy snow may be accompanied by winds greater than 15 mph and blowing snow. Make sure you listen to officials. You can follow our COSresponds Twitter list for updates from the City. C-DOT posts updates about road state road conditions and closures at http://cotrip.org. Your favorite local media outlet can be a good source of weather updates too. Stay off the roads if you can. If you do go out, make sure you have your vehicle emergency kit, give yourself extra time to get to your destination, and don’t crowd snow plows. 

A blizzard warning at lower elevations means the following condition are expected for at least three hours:

  1. Sustained winds at 35 mph or greater
  2. Considerable falling and/or drifting snow lowering visibility to less than one-quarter of a mile.

This is the time to stay hunker down where you are and stay off the roads. If you do get caught in your vehicle and become stranded, remember to:
  • Stay with your vehicle. Run your engine and heater for ten minutes every hour to stay warm. Be sure to open a window slightly to keep fresh air circulating.
  • Keep your exhaust pipe clear of snow or blockage.
  • Flash your headlights to signal for help but don’t leave lights on.
  • Know the make, model and color of your car.  You’ll want to share this information when calling emergency responders.
  • Note the closest cross streets.  This will help responders locate you.
  • Keep cell phone on low power mode, dim brightness, close extra apps, text when possible 

Winter Weather Advisories are issued when:

  • Snow accumulations are expected to be between four and eight inches within 12 hours in the mountains, and between three and six inches in 12 hours at lower elevations. 
  • Falling snow is accompanied by blowing snow causing lower visibility and travel problems.
  • When windblown snow will occasionally reduce visibility and create a hazard for travelers.
  • For freezing rain, drizzle, or a mix of precipitation types such as snow and sleet that will impact travel conditions.

Wind chill can make winter weather even more dangerous. A Wind Chill Warning is issued when there are wind chills of at least minus 25 degrees on the planes and minus 35 degrees in the mountains. A Wind Chill Watch means those conditions are possible in the next 12 to 36 hours. You don’t want to be out in cold like this for very long. Bundle up in layers and make sure you don’t have any exposed skin.  A Wind Chill Advisory is issued when wind and temperature combine to produce wind chill values of minus 18 degrees to minus 24 degrees across the plains and high valleys. In the mountains, the values are minus 25 to minus 25 degrees.

High Wind Warnings are a little different. They depend on the speed of the wind, rather than the temperature. A High Wind Warning is issued when there are sustained winds of 50 mph for at least one hour OR wind gusts to 75 mph for any duration in the mountains or foothills. Away from the foothills, the criteria are sustained winds of 40 mph for at least one hour or wind gusts to 58 mph for any duration. A High Wind Watch means those conditions are expected to develop in the next 12 to 36 hours.  

At home, make sure anything that can blow away is tied down or put in a safe place. High winds can make dangerous driving conditions, especially when it comes to large vehicles. 

Freeze watches and warnings are issued during the growing season in the spring and fall when freezing temperatures can cause damage to plants or crops. A Freeze Watch means there is potential for freezing conditions within the next 12 to 36 hours. A Freeze Warning means widespread sub-freezing temperatures (below 32 degrees) are imminent or highly likely. If you garden or farm, you’ll want to make provisions to keep your plants or crops from freezing. 

Definitions are taken from the NWS website.