Avalanche Advisory Archive Pre-2016
| Date Issued: | 2013-04-10 |
|---|---|
| Danger: | 1 |
| Trend: | 2 |
| Probability: | 4 |
| Size: | 1 |
| Problem: | 0 |
| Discussion: | TODAY...SNOW SHOWERS. SNOW ACCUMULATION TO 1 INCH. HIGHS AROUND TONIGHT...SNOW SHOWERS. SNOW ACCUMULATION TO 2 INCHES. LOWS AROUND 32. SOUTH WIND 5 TO 15 MPH. THURSDAY...RAIN AND SNOW SHOWERS LIKELY. SNOW ACCUMULATION TO 1 Our rain turned to snow about 4pm yesterday, earlier than anticipated, but snowfalls were minimal (about an inch) and winds were light, so new snow loading of the start zones is not a large hazard. The changeover from rain to snow was quick, so the skiff of new snow is not likely to bond well if the patchy sun persists throughout the morning but sizes of these slides will be tiny. The colder temps (almost -6c on Mt Juneau) are going to lock up the rest of the snowpack for us decreasing the danger until it either warms up or the snow accumulation becomes more significant. Avalanche Danger is LOW today: Natural avalanches of significant size unlikely, potentially destructive avalanches unlikely to come near or reach developed areas. Human triggered avalanches possible. In Urban Zones normal caution is advised. Backcountry Travel is generally safe. Normal caution is advised with particular attention to new snow over the recent rain crust to 4000ft. |
| Tip: | CLEAR SIGNS OF UNSTABLE SNOW The snowpack often displays visible, palpable and audible signs of unstable snow. These are warnings that indicate potentially dangerous conditions exist: * Whumpfing (the sound of snow collapsing) and cracking, especially shooting cracks. This suggests thick weak layers and cohesive slabs are primed for avalanches, given a sufficiently steep and open slope. When cracks visibly open across a slope because you were on it this is a sign of critical instability. * Recent avalanche activity suggests that slopes with similar characteristics in terms of elevation, aspect, incline, shape, etc. that have yet to produce avalanches are likely to be unstable. * Hollow sounds or sensations, like you?re walking on a drum. This suggests thin hard slabs with very little underlying support, and can indicate a thin snowpack area, where triggering is more likely, on an otherwise well covered slope that can produce a large avalanche. Take a look around, and if there are exposed rocks or trees scattered about, then you are likely in a thin snowpack area. * Difficult travel because you?re breaking trough heavy surface snow into underling light snow, which can also be felt by probing with a ski pole, ice axe, etc. This is also known as ?up-side down snow?, because light snow on top is the right side up for good riding, and can indicate wind slabs or storm slabs that are primed for avalanches. |
| Forecaster: | Chris Eckel |
