An upper level disturbance on the west coast moved southward over the southern Rockies and then out onto the southern plains from approximately December 21st through the 26th. This system affected the Cheyenne CWA in two waves. The first occurred December 22 and 23rd and brought light snow with strong winds that created drifting snow and hazardous driving conditions. As the storm system moved eastward, it intensified and brought heavy snow and blizzard conditions to the central Plains over the Holiday weekend.  A second wave of significant winter weather occurred over southeast Wyoming and the western Nebraska panhandle in wraparound energy from late on the 24th through the 26th.  Heavy snow and very strong winds produced blizzard conditions in the northeast portions of the CWA with near blizzard conditions elsewhere. Many roads were closed, including interstates 80 and 25 on Christmas day. Two deaths were indirectly attributed to to the second wave of winter weather, one near Laramie, WY and the other near Guernsey, WY.

Blizzard in NIOBRARA COUNTY, WYOMING
From 25-DEC-09 09:00:00 to 26-DEC-09 04:00:00 (MST-7)
Reported by: Law Enforcement

Blizzard conditions were seen across the east central Wyoming through Christmas day and continued through the following morning. Area roads were closed due to snow and blowing snow reducing visibilities and creating hazardous roads.  Local law enforcement reported visibilities down to 100 yards or less for most of the morning hours due to very strong winds. The winds made it difficult to discern whether it was snowing or if it was just blowing snow, but was estimated that 3 inches of snow had fallen as of 25/1245 MST. At 25/1500 MST, law enforcement reported a continuation of low visibility less than 200 yards due to blowing snow.  At 25/2045 MST, the AWOS at Lusk reported continuing visibility less than 1/4 mile with heavy snow and northwest winds of 32 MPH gusting to 39 MPH.  Similar conditions were reported again at 26/0201 MST with sustained winds of 37 MPH gusting to 48 MPH.  Regarding snowfall, a public report came in from Van Tassell at 26/0900 with an estimated 4 inches of snow and 3 ft drifts.

Winter Storm in FERRIS/SEMINOE/SHIRLEY MOUNTAINS, WYOMING
From 25-DEC-09 06:00:00 to 26-DEC-09 14:00:00 (MST-7)
Reported by: COOP Observer

Near blizzard conditions occurred over much of southeast Wyoming on Christmas day and continued through the late afternoon of the 26th. Area roads were closed due to snow and blowing snow reducing visibilities and creating hazardous driving conditions.  At 26/1024 MST, a CO-OP observer reported an estimated 6 to 10 inches of snow had fallen in the area with strong winds.

Winter Storm in LARAMIE VALLEY, WYOMING
From 25-DEC-09 10:00:00 to 26-DEC-09 16:00:00 (MST-7)
Reported by: Trained Spotter

A strong winter storm brought light snow and strong winds to the region. Many areas saw reduced visibilities and near blizzard conditions. At 1008 MST, a trained spotter located at 7S Laramie reported an estimated 2.5 inches of snow with strong winds.  Visibility was poor through much of the morning and was beginning to improve at this time.

Winter Storm in CENTRAL LARAMIE COUNTY, WYOMING
From 25-DEC-09 06:00:00 to 26-DEC-09 16:00:00 (MST-7)
Reported by: ASOS

Near blizzard conditions occurred over much of southeast Wyoming on Christmas day and continued through the late afternoon of the 26th. Area roads were closed due to snow and blowing snow reducing visibilities and creating hazardous driving conditions.  The ASOS at Cheyenne Airport reported a wind gust of 55 MPH at 25/1336 MST.  A Wyoming Department of Transportation site 4SSW of Cheyenne reported a gust of 58 MPH at 25/1340 MST. The combination of strong winds and snowfall created near blizzard conditions during this time.

Winter Storm in GOSHEN COUNTY, WYOMING
From 25-DEC-09 06:00:00 to 26-DEC-09 16:00:00 (MST-7)
Reported by: Trained Spotter

Near blizzard conditions occurred over much of southeast Wyoming on Christmas day and continued through the late afternoon of the 26th. Area roads were closed due to snow and blowing snow reducing visibilities and creating hazardous driving conditions.  A trained spotter reported an estimated 3 inches of snow fell as of 26/1016 MST. A lot of the snow had already blown away in strong winds, and there was some blowing dirt mixed in as well. The combination of snowfall and strong winds created near blizzard conditions during this time.

Winter Storm in CONVERSE COUNTY LOWER ELEVATIONS, WYOMING
From 25-DEC-09 06:00:00 to 26-DEC-09 16:00:00 (MST-7)
Reported by: Law Enforcement

Near blizzard conditions occurred over much of southeast Wyoming on Christmas day and continued through the late afternoon of the 26th. Area roads were closed due to snow and blowing snow reducing visibilities and creating hazardous driving conditions. A local law enforcement officer reported and estimated 7 to 8 inches of snow fell overnight, with 4 to 5 ft drifts in town due to very strong winds.

Winter Storm in EAST LARAMIE COUNTY, WYOMING
From 25-DEC-09 06:00:00 to 26-DEC-09 16:00:00 (MST-7)
Reported by: Department of Highways

Near blizzard conditions occurred over much of southeast Wyoming on Christmas day and continued through the late afternoon of the 26th. Area roads were closed due to snow and blowing snow reducing visibilities and creating hazardous driving conditions. The Department of Highways site at Gun Barrel reported a wind gust of 58 MPH at 25/1300 MST.  Local law enforcement reported an estimated 3 inches of snow fell near Pine Bluffs as of 26/1030 MST, with deeper drifts in town.  The combination of snowfall and strong winds created near blizzard conditions during this time.

Winter Weather in EAST PLATTE COUNTY, WYOMING
From 25-DEC-09 06:00:00 to 26-DEC-09 16:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Winter conditions occurred over much of southeast Wyoming on Christmas day and continued through the late afternoon of the 26th. Area roads were closed due to snow and blowing snow reducing visibilities and creating hazardous driving conditions.  Wind Chills were minus 10 to minus 15 degrees at the time the body was found.

Winter Storm in SOUTH LARAMIE RANGE, WYOMING
From 25-DEC-09 06:00:00 to 26-DEC-09 16:00:00 (MST-7)
Reported by: Department of Highways

Near blizzard conditions occurred over much of southeast Wyoming on Christmas day and continued through the late afternoon of the 26th. Area roads were closed due to snow and blowing snow reducing visibilities and creating hazardous driving conditions.  A Wyoming Department of Transportation sensor near Vedauwoo measured a wind gust of 60 MPH at 25/1347 MST. The combination of strong winds and snowfall created near blizzard conditions during this time.

Heavy Snow in SNOWY RANGE, WYOMING
From 25-DEC-09 01:00:00 to 25-DEC-09 20:00:00 (MST-7)
Reported by: Mesonet

A strong winter storm brought heavy snow to the Snowy Mountain Range in southeast Wyoming. From 25/0100 through 25/2000 MST, the SNOTEL site at South Brush Creek (elev. 8440 ft) had an estimated 12 inches of snow with 0.6 inches of snow water equivalent. During this same time, the SNOTEL site at Sand Lake (elev. 10,050 ft) had an estimated 14 inches of snow with 0.7 inches of snow water equivalent.

Winter Storm in SOUTH LARAMIE RANGE FOOTHILLS, WYOMING
From 25-DEC-09 06:00:00 to 26-DEC-09 12:00:00 (MST-7)
Reported by: Mesonet

Near blizzard conditions occurred over much of southeast Wyoming on Christmas day and continued through the late afternoon of the 26th. Area roads were closed due to snow and blowing snow reducing visibilities and creating hazardous driving conditions. At 25/1415 MST, a Union Pacific Railroad site at Emkay recorded a wind gust of 60 MPH. At 25/1425 MST, the Department of Transportation sensor at Whitaker measured sustained winds of 43 MPH with gusts of 55 MPH. Strong winds continued through the evening at the Emkay site with a gust of 61 MPH recorded at 25/1915 MST. Combined with recent snowfall, near blizzard conditions were occurring during this time.