Observation type
Snowpack Observer Allen Giernet Keep me anonymous if published no Location (general area) Kratka Ridge area Latitude 34° 21' 17" N Longitude -117° 53' 54" W Date (yyyymmdd) 2013/01/27 Time 12:48 Road conditions to area Clear and wet, upon driving out @ 4:30pm it was snowing steady to below 4000' and sticking Temperature -1°C Sky Obscured (fog or base layer prevents view of sky) Wind speed Calm (smoke rises vertically) Wind direction not observed Wind direction in degrees Slope aspect North West Aspect in degrees 320° Slope angle 38° Elevation 7500' Snow depth 20-40cm Boot/ Ski penetration 7.5cm Precipitation Light Activity, recent avalanches No Whumphing noises, shooting cracks. collapsing no Rapid warming no Obvious avalanche path no Terrain trap no Comment Snow was variable on the hike up 5 - 60cm from soft water saturated to solid ice, boot penetration varied from 2.5 to 30cm. I dug a pit at the 7500' level to get a look at what the rain had done to the snow on Northern aspects. I noticed first several times while isolating blocks to remove snow a layer jumped out with a Q1 quality though this is not quantifiable it is worthy of note. I performed 3 compression tests the first was CT12 Q1 8cm deep. The next 2 were CT2 Q3 & CT3 Q3 on the same layer I was not able to reproduce the Q1. Though several times I performed a shovel shear test and this same layer failed Q1 with very little pressure. The profile was: a thin rain crust on the surface (pencil hard) An 8cm layer of water saturated 2mm grains with absolutely no bonding (4 finger) A layer to the ground of well consolidated .5mm rounds though wet it was 1 finger The failure was the interface of the 4 finger 2mm wet loose snow on the consolidated .5mm layer. With colder weather the loose wet layer will most likely become a crust and over time should bond with the base layer until then it is a potential weak interface especially should we see some rapid loading. Though not apparent during travel through the area it is certainly something to be aware of. There was no sign of the faceted snow at the base I have found on every outing at each location I have visited this season. This may be an isolated situation. I also noticed there was no snow around the highway till just before Mt. Waterman and everywhere I could see (visibility was about 30 yards) southern aspects were almost completely melted out. Publish this observation Yes I would like this observation Published |
Kratka Ridge North aspect
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