A slow moving low pressure system moved from the Desert Southwest and into Southeastern Colorado.  As a result, a deep upslope flow developed along the Front Range and Northeast Plains of Colorado.  Strong winds and heavy snow brought blizzard conditions to the Interstate 25 Corridor, from the Wyoming state line south to Colorado Springs.
Storm totals generally ranged from 2 to 4 feet in and near the Front Range Foothills and Palmer Divide.  Across the Northeast Plains and in high mountain valleys of North and Middle Parks, storm totals ranged from 1 to 2 feet.  Strong winds gusting from 40 to nearly 60 mph during the storm produced drifts from 6 to 12 feet deep.
Denver measured 20.7 inches of snow officially, ranked as the 7th biggest snowstorm since 1946.  The storm forced the closure of Denver International Airport, stranding nearly 5,000 travelers as 2,000 flights were canceled.  D.I.A. remained closed for a total of 45 hours, the longest closure in its 12 year history.  Police and National Guardsman rescued hundreds of commuters stuck in the their cars, and sent them to temporary shelters set up by the Red Cross.  All highways and interstates, including I-25, I-70 and I-76 were shut down.  Mail delivery was also suspended.  RTD suspended its bus service for the first time since the March 2003 blizzard.  A roof at a discount storm in Aurora collapsed under the weight of the snow.  In Lakewood, a power outage left 5,600 residents without electricity briefly.

Winter Storm in JEFFERSON & W DOUGLAS COUNTIES ABOVE 6000 FEET / GILPIN / CLEAR CREEK / NE PARK COUNTIES BELOW 9000 FEET, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Storm totals in the Front Range Foothills included:  44 inches, 7 miles north of Glen Haven, 42 inches at Conifer and 11 miles southwest of Boulder, 40 inches at Evergreen, 39 inches at Aspen Springs, 37.5 inches, 8 miles north of Blackhawk, 37 inches near Conifer, 33 inches near Nederland, 31 inches at Intercanyon and near Tiny Town, 30.5 inches near Buckhorn Mountain, 30 inches near Indian Hills, 29 inches at Rollinsville, 24 inches at Gross Reservoir and 9 miles west-southwest of Rustic, 22.5 inches at Crow Hill, 21 inches at Cheesman and Pine Junction, and 20 inches near Georgetown.

Blizzard in MORGAN COUNTY, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Blizzard in C & E ADAMS & ARAPAHOE COUNTIES, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Blizzard in SEDGWICK COUNTY, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Storm in S & E JACKSON / LARIMER / N & NE GRAND / NW BOULDER COUNTIES ABOVE 9000 FEET, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 10:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Storm in LARIMER & BOULDER COUNTIES BETWEEN 6000 & 9000 FEET, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Blizzard in N & NE ELBERT COUNTY BELOW 6000 FEET / N LINCOLN COUNTY, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Blizzard in PHILLIPS COUNTY, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Storm totals included:  21 inches, 21 miles north of New Raymer, 20.5 inches near Greeley, 20 inches near Byers, 18 inches, 11 miles southwest of Haxtun, 17 inches at Holyoke and near Strasburg, 14 inches, 18 miles southwest of Fleming, Hereford and Iliff, 13 inches, 4 miles southeast of Holyoke, 8 miles southeast of Matheson, 12 inches near Leroy, with 10 inches near Lindon, Sedgwick, Windsor and Woodrow.
Peak wind gusts included:  58 mph at Crook, 54 mph at Greeley, 51 mph at Limon, 44 mph, 21 miles north of New Raymer and 15 miles north-northwest of Sterling and 43 mph at Akron.

Blizzard in SE ELBERT COUNTY BELOW 6000 FEET / SOUTH LINCOLN COUNTY, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Storm in S & SE GRAND / W CENTRAL & SW BOULDER / GILPIN / CLEAR CREEK / SUMMIT / N & W PARK COUNTIES ABOVE 9000 FEET, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 10:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

An slow moving upper level low pressure system moved from the Desert Southwest and into Southeastern Colorado.  As a result, a moist and very deep easterly flow brought heavy snow to the Front Range of Colorado.  Storm totals generally range from 1.5 to 4 feet.
Storm totals in the North-Central Mountains included:  48 inches at Hourglass Reservoir, 26 inches at Roach Snotel, 25.5 inches at Rawah Snotel, 24.5 inches at Willow Park, 24 inches at Bear Lake, 23 inches at Lake Irene, 21 inches at Deadman Hill, 20 inches at Cabin Creek and Lake Eldora, 18 inches at Winter Park, 17.5 inches at Echo Lake, 16 inches at the Arrow and Berthoud Snotel sites.

Blizzard in LOGAN COUNTY, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Blizzard in WASHINGTON COUNTY, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Blizzard in BOULDER & JEFFERSON COUNTIES BELOW 6000 FEET / W BROOMFIELD COUNTY, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 10:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Blizzard in ELBERT / C & E DOUGLAS COUNTIES ABOVE 6000 FEET, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Blizzard in NE WELD COUNTY, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Storm in GRAND & SUMMIT COUNTIES BELOW 9000 FEET, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 06:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Blizzard in C & S WELD COUNTY, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Storm in JACKSON COUNTY BELOW 9000 FEET, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 06:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

In North and Middle Parks storm totals included:  26 inches near Rand, 14.5 inches at Fraser and 10 inches at Walden.

Blizzard in LARIMER COUNTY BELOW 6000 FEET / NW WELD COUNTY, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 10:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Blizzard in N DOUGLAS COUNTY BELOW 6000 FEET / DENVER / W ADAMS & ARAPAHOE COUNTIES / E BROOMFIELD COUNTY, COLORADO
From 20-DEC-06 06:00:00 to 21-DEC-06 12:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Storm totals along the Urban Corridor included:  34 inches, 10 miles south-southeast of Buckley AFB, 32 inches at Littleton, 30 inches near Castle Rock and Thornton, 29.5 inches near Parker, 28 inches at Wheat Ridge, 26 inches at Castle Rock, 25.5 inches at Centenniel, 25 inches at Niwot, 24 inches at Aurora, near Loveland and Ralston Reservoir, 22.5 inches at Greenwood Village, 22 inches at Arvada, 21.5 inches at Lakewood, 21 inches at Fort Collins, 20 inches at Longmont,  with 15.5 inches in Boulder.
Peak wind gusts included:  55 mph at Denver International Airport,  46 mph at Elbert, 48 mph at Fort Collins/Loveland, 41 mph near Wellington and 40 mph at Centenniel.