Understanding Advisories, Watches and Warnings
It's important to know the difference between various weather warnings, especially if you're planning on traveling. Understanding what these warnings are and what they mean will help keep you and your family safe when winter weather hits.
- Winter Storm Outlooks are issued when there is a chance of a major winter storm coming anywhere from 3 to 5 days in the future. This warning is meant to assist people with their long range plans. However, since the outlook is issued so far in advance, the accuracy of the prediction may be limited.
- Winter Weather Advisories are issued when snow, blowing snow, ice, sleet, or a combination of these has a good chance of occurring. It means the bad weather is expected but conditions should not be hazardous enough to meet Warning criteria. Be prepared for winter driving conditions and possible travel difficulties. Use caution when driving.
- Winter Storm Watches are long-range predictions that mean there may be hazardous winter weather due to heavy snow, sleet, or ice accumulation from freezing rain. They are generally issued at least 24 hours before the hazardous winter weather is expected to begin. When the storm becomes imminent, or has a high probability of occurring, the watch will be upgraded to a Winter Storm Warning.
- Winter Storm Warnings are issued when a dangerous combination of heavy snow, with sleet and/or freezing rain, will occur or has a high probability of occurring within the next 12 hours. Warnings are usually issued for smaller geographic areas and usually for shorter, more specific time periods. Travel will become difficult or impossible in some situations. It's best to delay travel plans until conditions improve.
- Winter Storm Warnings for Severe Icing can occur in higher elevations. Heavy accumulation of ice due to freezing rain can knock down trees and power lines. Electricity, or telephone communications, may be out for a long period of time and roads may become impassable for most vehicles.
- Blizzard Warnings are issued when a combination of strong winds averaging or frequently gusting up to and above 35 miles an hour, with very low visibility due to blowing or falling snow. These are the most dangerous winter storms and can be especially severe when the temperature drops below 10 degrees.
- High Wind Warnings are issued when expected winds will average 40 miles an hour or more for at least 1 hour or winds gusts will be greater than 58 miles an hour. Trees and power lines can be blown down. A High Wind Warning may be preceded by a High Wind Watch if the strong winds are not expected to occur for at least 12 hours.
- Wind Chill Advisories are issued when the forecast predicts cold temperatures and winds, with wind chill temperatures at minus 25 degrees or less for at least 3 hours. Exposure to this combination of strong winds and low temperatures without protective clothing can lead to frostbite and/or hypothermia. Prolonged exposure may be fatal.
- Wind Chill Warnings mean life-threatening cold with wind chill temperatures are predicted to be minus 40 degrees or less for at least 3 hours. Exposure to this combination of strong winds and low temperatures without protective clothing will quickly lead to frostbite and/or hypothermia. Longer exposures can be fatal.