Mother's Day Storm Summary

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A strong spring storm system brought significant snowfall to southeast Fremont, eastern Sweetwater, southern Casper and Casper Mountain.  Along with the snowfall strong north to northeast winds caused considerable blowing and drifting of snowfall especially above 7000 feet.  Accumulating snowfall varied considerably across Casper with around one inch across northwest and northern Casper to between 4 and 7 inches at the base of Casper Mountain in the Outer Drive area.  Casper Mountain was the big winner for snowfall with around 2 feet of snow with the east side of the Wind River Mountains coming in a close 2nd with 1 to 2 feet.  This snow and wind caused several major highways to be closed for 12 to 24 hours including much of Interstate 80.

Casper Mountain Snowfall Measurement  Trucks backed up west of Cheyenne at "Roundtop" on Interstate 80 Sunday evening. Interstate 80 remained closed through Monday morning. - Click to enlarge
 The snow piling up to near 2 feet on Casper Mountain.

Trucks backed up west of Cheyenne at "Roundtop" on Interstate 80 Sunday evening. Interstate 80 remained closed through Monday morning.


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Snowfall Totals
County Location Snowfall
Big Horn Bone Springs Divide Snotel 3
Big Horn Bald Mountain Snotel 3
Big Horn Powder River Pass 2
Big Horn Shell Creek Snotel 2
County Location Snowfall
Fremont Townsend Creek Snotel 22
Fremont Hobbs Park Snotel 19
Fremont South Pass Snotel 18
Fremont 9.5 SW Lander 14
Fremont Deer Park Snotel 14
Fremont St. Lawrence Alt Snotel 13
Fremont 6 SW Lander 11.1
Fremont Atlantic City 10
Fremont 9 S Lander 9
Fremont Jeffrey City 9
Fremont 9 SSE Lander 7.5
Fremont 3 SW Lander 7.5
Fremont 6.6 SW Lander 7
Fremont 9 SSE Lander 5.5
Fremont 5 W Lander 5
Fremont Cold Springs Snotel 5
Fremont 7 WNW Lander 4.7
Fremont Little Warm Snotel 4
Fremont 2 SSW Arapahoe 3
Fremont 1 SW Lander 2.8
Fremont Lander Town
1.5 to 2.5
Fremont Riverton 1.8
Fremont Hudson 1.5
Fremont Riverton Airport 1.4
Fremont Lander Airport 1.2
Fremont Dubois 1
County Location Snowfall
Johnson Cloud Peak Reservoir Snotel 4
Johnson Bear Trap Meadow Snotel 3
Johnson Hansen Sawmill Snotel 3
Johnson Little Goose Snotel 3
Johnson Soldier Park Snotel 1
County Location Snowfall
Lincoln 5 NNE Thayne 4
Lincoln 5 SSE Smoot 3
Lincoln 2 SE Thayne 3
Lincoln Afton 0.4
County Location Snowfall
Natrona Casper Mountain 20 to 23
Natrona Reno Hill Snotel 23
Natrona Casper Mountain Snotel 20
Natrona 5 SSW Casper 7
Natrona 2 S Casper 6.3
Natrona 4 SW Casper 6.3
Natrona 10 WSW Casper 5.2
Natrona 3 SW Casper 4.6
Natrona Casper 4.6
Natrona 4 WSW Casper 3.2
Natrona 11 ESE Casper 2.1
Natrona Powder River 2
Natrona Grave Spring Snotel 2
Natrona Casper Airport 0.9
Natrona 12 NE Lysite 0.4
County Location Snowfall
Park Beartooth Lake Snotel 5
Park Kirwin Snotel 4
Park Marquette Snotel 3
Park 26 SW Cody 1.5
Park Evening Star Snotel 1
Park Blackwater Snotel 1
Park 4 SE Cody 0.6
Park 5 ESE Cody 0.5
County Location Snowfall
Sublette Pinedale 2.5
Sublette Kendall Ranger Station Snotel 1
Sublette Big Piney 0.5
County Location Snowfall
Sweetwater Wamsutter 6
Sweetwater 7 SSE Rock Springs 3.1
Sweetwater Green River 3
Sweetwater Green River 2
Sweetwater 7 SE Rock Springs 0.4
County Location Snowfall
Washakie Middle Powder Snotel 3
Washakie 27 S Ten Sleep 0.4
24-hour precipitation (liquid) totals from Sunday morning to Monday morning.
The map below is automatically generated and no quality controls have been done on this data, but it clearly shows where the heaviest precipitation fell.
24 hour precipitation (liquid) from Sunday morning to Monday morning.

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Notable Wind Gusts during the Mother's Day Storm
County Location Wind Gust (mph)
 Fremont  Top of Boysen Reservoir (7300 FT) 66
 Sweetwater  I-80 Mile Marker 184 56
 Fremont  8 W South Pass City (8120 FT) 55
 Sweetwater  Rock Springs Airport (6759 FT) 54
 Big Horn  30 E Greybull (8898 FT) 54
 Fremont  2 W South Pass City (8185 FT) 53
 Johnson  12 N Kaycee (5287 FT) 50




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