Observation: Provo Peak 3/2/2010

Observer Name:

Patterson

Region:

Provo
Provo Canyon
Provo Peak

Observation Date:

03/02/2010

Location or Route:

Sqauw Peak Road-Provo Peak

Weather

Sky:

Broken

Wind Direction:

South

Wind Speed:

Light

Weather Comments:

High clouds all day with patches of blue sky above. Winds were light out of the South. warm. measured +1C around 1pm. Sun was not getting through and affecting snow surface. heating kept in check by high clouds.

Snow Characteristics

Snow Surface Conditions:

Dense Loose

Wind Crust

Snow Characteristic Comments:

Mixed bag out there. most aspects had a temp/sun crust except due north where some small grained 1-2mm surface hoar existed and dense settled pow.

Primary Concern

Primary Concern:

Persistent Slabs

Probability:

Moderate

Aspect:

North

Elevation:

Mid

Low

Trend:

Same

Primary Concern Comments:

Mostly concerned with the lingering surface hoar instabilities out there. 2 buried layers from the 10th and 17th of February are a concern in the Provo area mountains. I was curious to see which layer was more reactive today.

snow_profile_location:

Comments - Photos - Videos (group 1)

On my way in to Provo Peak i noticed what appeared to be a natural on an east aspect at a lower elevation. It didn't look like a very deep avalanche, but what was interesting was how far it propagated. It's speculation, but likely that surface hoar was the culprit.

Comments - Photos - Videos (group 2)

Dug a hole around 9800', NNW aspect, 34 degrees. I was able to pop out a surface hoar layer with a tilt test easily. Now the question was whether it was the 2/17 layer or the 2/10 layer? A compression test pulled it out again with 14 taps, Q1, and when the block slide out, a clean shear broke out beneath it. Easy to see that the upper layer was the 2/17 SH, and the lower one the 2/10 layer, both 2-3mm crystals. Continued tests revealed the 2/17 layer to be more reactive, mostly with Q2 failures. This follows with what I have been seeing in the Provo area mountains over the last couple of weeks. Good propagation as well on the 2/17 layer, with an ECTP17 Q2. The structure here is poor due to these surface hoar layers, but they don't feel completely reactive right now. That could change if the forecasted Thurs/Fri. storm verifies. The question looms...do these layers exist up high?

Comments - Photos - Videos (group 3)

Visual of the 2/17 and 2/10 surface hoar layers from a second compression test

Comments - Photos - Videos (group 4)

Observed Danger Rating:

Moderate

Forecast Danger Rating:

Moderate