Winter Weather Warning Terms

The following terms WARN the public of more serious winter weather situations that may cause impossible traveling conditions and could pose a threat to life and property.

PRODUCT Description
WINTER STORM WATCH (WSA)
Issued when conditions are favorable for the development of hazardous weather elements, such as heavy snow or sleet, blizzard conditions, significant accumulations of freezing rain or drizzle, or any combination thereof.  Watches are usually issued 12 to 48 hours in advance of an event.
WINTER STORM WARNING (WSW)
An all-encompassing product now that replaces the old blizzard warnings, heavy snow warnings, sleet warnings, and ice storm warnings.  This product is used when hazardous winter weather conditions are imminent or very likely, including any occurrence or combination of heavy snow, wind-driven snow, sleet, and/or freezing rain/drizzle.  Winter Storm Warnings are issued for expected sleet and snowfall amounts of 4 inches or more in 12 hours, or 6 inches or more in 24 hours.  It is also used when damaging ice accumulations are expected during freezing rain situations; walking and driving becomes extremely dangerous, and ice accumulations are usually 1/4 inch or greater.  Finally, it is also issued with sustained winds or frequent gusts of 35 miles per hour or greater and considerable falling and/or blowing snow reducing visibility to less than 1/4 mile.  These conditions are expected to last at least 3 hours.

 


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