Winter Weather Event Criteria

 

National Weather Service Salt Lake City

Winter Weather Event Criteria

 

Issuance Time

12 hour criteria

24 hour criteria

Winter Storm Watch

2nd, 3rd, and 4th period

Issued for criteria meeting Winter Storm Warning criteria

Winter Storm Warning

1st and 2nd period

UT Dixie/Zion: 2"+

Valleys/WY: 6"+

Mtn Valleys: 8"+

Mountains: 12"+

UT Dixie/Zion: 4"+

Valleys/WY: 9"+

Mtn Valleys: 12"+

Mountains: 18"+

Winter Weather Advisory

1st and 2nd period

UT Dixie/Zion: 1"

Valleys/WY: 3 to 5"

Mtn Valleys: 4 to 7"
Mountains: 6 to 11"

UT Dixie/Zion: 2 to 3"

Valleys/WY: 4 to 8"

Mtn Valleys: 6 to 11"

Mountains: 7 to 17"

Blizzard Watch

2nd, 3rd, and 4th period

Issued for criteria meeting Blizzard Warning

Blizzard Warning

1st and 2nd period

Conditions lasting 3 hours or more including sustained winds or gusts 35 mph or greater with considerable blowing and drifting of snow with visibilities less than 1/4 mile

Lake Effect Snow Watch

Mainly 2nd or 3rd period

Issued for criteria meeting Lake Effect Snow Warning (valleys only)

Lake Effect Snow Warning

Typically within 12 hours of event

6" or more (valleys only)

9" or more
(valleys only)

Wind Chill Watch

2nd, 3rd, and 4th period

Issued for criteria meeting Wind Chill Warning

Wind Chill Warning

1st and 2nd period

Wind chills of -30F or less and winds 10 mph or greater for 3 hours or more

 

 

 

 

Lake Effect Snow Advisory

Typically within 12 hours of event

3 to 5"
(valleys only)

4 to 8"
(valleys only)

Ice Storm Warning

1st and 2nd period

0.25" or more ice accumulation

Freezing Rain/Drizzle Advisory

1st and 2nd period

Ice accumulation less than 0.25", particularly when accumulation of ice is impacting area roads and travel

 

National Weather Service Grand Junction

Winter Weather Event Criteria

 

Visit the National Weather Service Grand Junction web page at http://www.crh.noaa.gov/gjt/?n=gjt_criteria
for eastern
Utah winter weather event criteria.