An unusually cold late winter storm moved into Southern Oregon and Northern California during this interval.  Numerous Heavy Snow Warnings were issued for this system along with a number of Snow Advisories.
Issued              Effective Time    Warning      Zone(s)
February 20/0413    20/1000-20/2200   Heavy Snow   CAZ080 >3000 feet
extended to 20/1900 to 21/1000 at 20/1521
extended to 22/1000 at 21/0419
downgraded to Snow Advisory at 22/0407.
February 20/0413    20/1600-21/1000   Heavy Snow   CAZ082/083 >3000 feet
extended to 20/1900 to 22/1000 at 20/1521
downgraded to Snow Advisory at 22/0407.
February 21/1412    21/1412-22/1200   Heavy Snow   CAZ084
downgraded to Snow Advisory at 21/0407.
February 21/2043    20/2043-22/1000   Heavy Snow   CAZ081
downgraded to Snow Advisory at 22/0407.

Heavy Snow in WESTERN SISKIYOU COUNTY, CALIFORNIA
From 21-FEB-07 08:00:00 to 22-FEB-07 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The cooperative observer at Fort Jones recorded 12 inches of snow in 24 hours.

Heavy Snow in CENTRAL SISKIYOU COUNTY, CALIFORNIA
From 21-FEB-07 20:00:00 to 22-FEB-07 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter 6N Weed reported 13 inches of snow in 12 hours, with a 24 hour total precipitation of 2.73 inches.

Heavy Snow in SOUTH CENTRAL SISKIYOU COUNTY, CALIFORNIA
From 21-FEB-07 18:00:00 to 22-FEB-07 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter 4SSW Weed reported 18 inches of snow in 14 hours, 16 of them in the past 10 hours.

Heavy Snow in CENTRAL SISKIYOU COUNTY, CALIFORNIA
From 21-FEB-07 08:00:00 to 22-FEB-07 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The coop observer at Yreka recorded 12.5 inches of snow in 24 hours.

Heavy Snow in CENTRAL SISKIYOU COUNTY, CALIFORNIA
From 21-FEB-07 16:00:00 to 22-FEB-07 04:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter 1N Yreka reported 12 inches of snow in 12 hours.

Heavy Snow in SOUTH CENTRAL SISKIYOU COUNTY, CALIFORNIA
From 22-FEB-07 00:00:00 to 22-FEB-07 07:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter 1W Mount Shasta reported 7 inches of snow in 7 hours.

Heavy Snow in WESTERN SISKIYOU COUNTY, CALIFORNIA
From 21-FEB-07 09:00:00 to 22-FEB-07 05:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Spotter SY103 2 SSW Fort Jones at 2728 feet reported 12 inches of snow in 20 hours.

Heavy Snow in SOUTH CENTRAL SISKIYOU COUNTY, CALIFORNIA
From 21-FEB-07 16:00:00 to 22-FEB-07 12:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter 4SW Weed reported 13 inches of snow in 20 hours, with storm total of 20 inches.

Heavy Snow in SOUTH CENTRAL SISKIYOU COUNTY, CALIFORNIA
From 20-FEB-07 17:00:00 to 21-FEB-07 17:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Park/Forest Service

Reported by Mt. Shasta Avalanche Center.  Site was Mt. Eddy at 5900 feet.

Heavy Snow in NORTHEAST SISKIYOU AND NORTHWEST MODOC COUNTIES, CALIFORNIA
From 21-FEB-07 20:00:00 to 22-FEB-07 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter 4E MacDoel reported 13 inches of snow in 12 hours.

Heavy Snow in SOUTH CENTRAL SISKIYOU COUNTY, CALIFORNIA
From 21-FEB-07 16:00:00 to 22-FEB-07 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter 3NW Weed reported 16 inches of snow in 16 hours.

Heavy Snow in NORTHEAST SISKIYOU AND NORTHWEST MODOC COUNTIES, CALIFORNIA
From 21-FEB-07 18:00:00 to 22-FEB-07 06:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter north of Dorris reported 9.5 inches of snow in 12 hours.  13 inches on the ground.

Heavy Snow in SOUTH CENTRAL SISKIYOU COUNTY, CALIFORNIA
From 21-FEB-07 04:00:00 to 21-FEB-07 16:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter 4SW Weed recorded 7 inches of snow in 12 hours.

Heavy Snow in SOUTH CENTRAL SISKIYOU COUNTY, CALIFORNIA
From 20-FEB-07 22:00:00 to 21-FEB-07 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Park/Forest Service

Reported by Mt. Shasta Avalanche Center.  Site was Castle Lake at 5870 feet.  24 inches in 24 hours, 16 inches in 12 hours.  Storm total 27 inches.

Heavy Snow in WESTERN SISKIYOU COUNTY, CALIFORNIA
From 21-FEB-07 10:00:00 to 21-FEB-07 22:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Reported by spotter SY23 north of Fort Jones at 2680 feet.  6 inches in 12 hours.

Heavy Snow in WESTERN SISKIYOU COUNTY, CALIFORNIA
From 21-FEB-07 08:00:00 to 22-FEB-07 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Spotter SY22 2SSW Etna at 3500 feet reported 12 inches of snow in 24 hours.

Heavy Snow in SOUTH CENTRAL SISKIYOU COUNTY, CALIFORNIA
From 21-FEB-07 08:00:00 to 22-FEB-07 08:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter 6NW Mount Shasta reported 20 inches of snow in 24 hours.

Heavy Snow in NORTHEAST SISKIYOU AND NORTHWEST MODOC COUNTIES, CALIFORNIA
From 20-FEB-07 21:00:00 to 21-FEB-07 10:00:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Reported by spotter near Dorris, California.  7 inches fell during the first six hours of the event.  11 inches in 13 hours.