A moist and unseasonably cold upper low tracked slowly eastward across western Colorado and produced heavy snow accumulations in some mountain areas.

Heavy Snow in GORE AND ELK MOUNTAINS/CENTRAL MOUNTAIN VALLEYS, COLORADO
From 09-MAY-15 15:00:00 to 11-MAY-15 10:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Snowfall totals of 4 to 12 inches were measured across the area.  Locally higher amounts included 16 inches on independence Pass and 14 inches at Vail Ski Area. I-70 at Vail Pass was closed for a period of time due to vehicle accidents.

Heavy Snow in WEST ELK AND SAWATCH MOUNTAINS, COLORADO
From 08-MAY-15 17:00:00 to 11-MAY-15 01:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Snowfall totals of 5-11 inches were measured across the area.  Locally higher amounts included 14 inches at the Porphyry Creek SNOTEL site.  Higher elevations roads became snowpacked and chains were required for trucks traveling on Highway 50 over Monarch Pass.

Winter Weather in ELKHEAD AND PARK MOUNTAINS, COLORADO
From 08-MAY-15 10:00:00 to 11-MAY-15 00:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Snowfall totals of 2 to 6 inches were measured across the area.  Locally higher amounts included 10 inches at the Tower SNOTEL site.

Winter Weather in GRAND AND BATTLEMENT MESAS, COLORADO
From 08-MAY-15 18:00:00 to 10-MAY-15 10:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Snowfall totals of 2 to 8 inches were measured across the area.  Locally higher amounts included 10 inches at the Tower SNOTEL site.

Winter Weather in FLATTOP MOUNTAINS, COLORADO
From 08-MAY-15 09:00:00 to 10-MAY-15 13:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Snowfall totals of 3 to 6 inches were measured across the area.  Locally higher amounts included 8 inches at the Bison Lake SNOTEL site.

Heavy Snow in SOUTHWESTERN SAN JUAN MOUNTAINS, COLORADO
From 08-MAY-15 18:00:00 to 11-MAY-15 01:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Snowfall totals of 4 to 12 inches were measured across the area.  Locally higher amounts included 16 inches at the Sharkstooth SNOTEL site. Numerous vehicle accidents occurred due to the slick roads.

Winter Weather in UPPER YAMPA RIVER BASIN, COLORADO
From 09-MAY-15 01:00:00 to 10-MAY-15 13:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

Snowfall totals of 2 to 6 inches were measured across the area.  Locally higher amounts included 9 inches at Oak Creek.  Slick roads resulted in a number of vehicle accidents in the Steamboat Springs area.

Winter Weather in UNCOMPAHGRE PLATEAU AND DALLAS DIVIDE, COLORADO
From 08-MAY-15 17:00:00 to 10-MAY-15 14:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Snowfall totals of 5 to 6 inches were measured above the 8000 foot level.

Heavy Snow in NORTHWESTERN SAN JUAN MOUNTAINS, COLORADO
From 08-MAY-15 17:00:00 to 10-MAY-15 19:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Snowfall totals of 4 to 11 inches were measured above the 8000 foot level.