Details

• Date: 2011/02/24

• Observer: Brian Lazar
• Organization: Forecast Staff, Colorado Avalanche Information Center

Location

• BC Zone: Front Range
• Area Description: Rock Mtn. Natl. Park. North facing slopes above Dream Lake.

Weather

• Ridgeline Wind Speed: 10-20 mph
• Ridgeline Wind Direction: SW
• Wind Loading: Moderate
• Temperature: 22 F
• Sky Cover: Overcast
• Depth of New Snow: 5 cm
• Depth of Total Snow: 235 cm
• Most Significant Precip Rate: S2 - 2 cm/hr
• Weather Description: mild temps, overcast skies, snowing most of the day; mainly s-1, but periods of up to S2. 2 inches on the ground at 10am, and a total of 5-6 inches had fallen by the time I left the parking lot at 2PM.

Snowpack

• Snowpack Description: Deep snowpack for RMNP. Over 2m on the ground nearly all locations even BTL. 5-6 inches of low density had fallen on top of mixed bag of older surface conditions. This snow had already blown into 8-12" on lee aspects...mainly N through east. Crusts made up old snow surface on nearly all aspects BTL. Temperatures appear to have gotten warm enough during last warm spell to form firm temp crust even on N'erthly aspects. New storm snow not bonding all that well. Witnessed and caused widespread sluffing of new (and currently falling) storm snow. Winds were strong enough to start to stiffen up storm slab even BTL, and produce some cracking. Natural and skiers triggered soft storm slabs were encountered....see avy obs.

Snowpack Obsvervation #1 Cracking: Minor Collapsing: Minor Persistent Weak Layer: Yes Comments: Traveled a variety of aspects near and BTL. Most places had either MFC and/or sun crusts. New snow easily sliding off old snow surface. N aspects had facet layer 30-40 cm below crust and 20-30 cm P hard windslab. Not reactive, but could potentially be a problem in more exposed and wind-loaded areas.

Avalanches

	Date	Location/Path	#	Elev	Asp	Type	Trig	SizeR	SizeD
	2011/02/24	Rocky Mountain National Park	1	TL	N	L	N	R1	D1
Date: 2011/02/24 Observer: Brian Lazar Organization: Forecast Staff, Colorado Avalanche Information Center Landmark: Rocky Mountain National Park Comments: numerous small loose dry slough in strom snow. All aspects BTL.
	2011/02/24	Rocky Mountain National Park	1	TL	N	SS	N	R1	D1
Date: 2011/02/24 Observer: Brian Lazar Organization: Forecast Staff, Colorado Avalanche Information Center Area Description: Dream Chutes. Mainly N-NE-E aspects. Landmark: Rocky Mountain National Park Average Slope Angle: 38 ° Maximum Slope Angle: 45 ° Elevation: 10600 ft Average Crown: 10 in Maximum Crown: 20 in Average Width: 30 ft Maximum Width: 50 ft Average Vertical: 300 ft Maximum Vertical: 400 ft Comments: numerous...see decsription below