Winter Storm | Alerts and Warnings

 

 

 

 

 

Description

HelpRepresentative statement of current Protective Action guidance that was used as the basis for validation; not exact or complete current guidance language.

 

  • Alerts are issued by regional NWS and may vary by region. NWS alerts for winter weather: 

    • Winter Weather Advisory: when conditions are expected to cause significant inconveniences that may be hazardous.

    • Winter Storm Watch: severe winter conditions may affect your area but the location and timing are still uncertain; issued 12 to 36 hours in advance of a potential storm.

    • Winter Storm Warning: 4 or more inches of snow or sleet are expected in the next 12 hours, or 6 or more inches in 24 hours, or ¼ inch or more of ice accumulation is expected. The NWS may also issue a warning if the storm is expected to hit during high-traffic times..

Normally, a Winter Storm Watch will be issued in advance of the storm (usually at least 24 hours). It indicates the risk of a hazardous winter weather event has increased (at least a 50% chance of it occurring), but its occurrence, location, and/or timing is still uncertain. It is intended to provide enough lead time so you can make plans to stay safe. While rare for our area, a Blizzard Watch may be issued instead. 

As the event becomes imminent, a watch will normally be upgraded to either a warning or an advisory (which indicates an 80% or greater probability of occurence). A Warning indicates that conditions pose a threat to life or property, and that travel will become difficult to impossible. An Advisory indicates conditions pose a significant inconvenience, and if caution is not exercised, could lead to situations that may threaten life and/or property. 

There are 3 types of warnings issued by our office:

  • A Winter Storm Warning indicates that heavy snow of at least 6 inches in 12 hours, or at least 8 inches in 24 hours, is expected. It can also be issued if sleet accumulation will be at least half an inch. 

  • An Ice Storm Warning indicates that ice accumulation of at least 1/4 inch is expected.

  • A Blizzard Warning indicates that blizzard conditions (low visibility of less than 1/4 mile due to falling and/or blowing snow, and winds at least 35 mph) are expected for at least 3 hours. 

There are two types of advisories issued by our office:

  • A Freezing Rain Advisory indicates that ice accumulation of up to 1/4 inch is expected.

  • A Winter Weather Advisory is issued for one or more of the following:  Snow of 3 to 5 inches in 12 hours, sleet accumulation up to 1/4 inch, freezing rain in combination with sleet and/or snow, or blowing snow. 

For more winter preparedness information, visit The National Weather Services  Winter Weather Preparedness page.