Observation: North Fork Provo R.

Observation Date
01/5/2017
Observer Name
Hardesty

Region:

Location Name or Route
North Fork of Provo
Weather
Sky
Overcast
Precipitation
Light Snowfall
Wind Speed
Calm
Weather Comments
Mid mountain storm started 11pm Tuesday night: HST: 29"/4.47"....of interest 1.45" fell over 4 hour period Wednesday evening 6pm 10pm This fell on the low density snow from earlier in the week.
Snow Characteristics
New Snow Depth
2.5'
New Snow Density
High
Snow Surface Conditions
Powder
Snow Characteristics Comments

Heavy but rode well.

Red Flags
Red Flags
Recent Avalanches
Heavy Snowfall
Wind Loading
Cracking
Collapsing
Poor Snowpack Structure
Red Flags Comments
Significant avalanche cycle in the Provo mountains january 4 overnight into january 5. Many aspects and elevations; generally size 2 to 3.5
Avalanche Problem #1
Type
Persistent Slab
Trend
Decreasing Danger
Problem #1 Comments

These went natural, remote, and sympathetic last night into today.  ESE to North aspects generally below 7500'.  Up to 1 to 2 to 2.5' deep and 100' wide running on 12/16 facet above rain crust combo.  I collapsed a slope at 6400'.  All in uncompacted terrain.  2cm of 4F damp facets above the Dec 16 crust.  Note structure with facets at the base.  


 

Avalanche Problem #2
Type
Storm Slab
Trend
Decreasing Danger
Problem #2 Comments

Above 7500', the avalanches seemed to be all about the new snow with a graupel layer prominent 18-24" down...or on the low density snow from earlier in the week. Many aspects.  Graupel layer clearly observed in profile


Comments

Plow triggered side cut slides to the ground or to the facets around the 12/16 rain crust.  

Natural or sympathetic 2' deep and 250' wide on ESE in lower Primrose Cirque 7500' or so .  

  • another view of the persistent slab avalanche; possibly natural; possibly sympathetic to natural off the UFO Bowl/Primrose ridge
  • Primrose Cirque would have been a death trap overnight: naturals out of NE chute of Elk Point overrunning the standard hiking trail; and further up-canyon an ESE slide path takes out small trees and running over toward the other debris from Elk Point.
  • Theater in the Pines avalanche path - debris runs to within a few hundred yards of the aspen grove parking lot.  
Today's Observed Danger Rating
Considerable
Tomorrows Estimated Danger Rating
Considerable
Snow Profile Coordinates