Avalanche Advisory Archive Pre-2016
| Date Issued: | 2012-12-23 |
|---|---|
| Danger: | 1 |
| Trend: | 3 |
| Probability: | 1 |
| Size: | 1 |
| Problem: | 0 |
| Discussion: | The National Weather Service Forecasts- TODAY...MOSTLY CLOUDY. HIGHS 15 TO 21. NORTHEAST 10 TO 20 MPH. TONIGHT...MOSTLY CLOUDY. LOWS 10 TO 20...EXCEPT AROUND 3 BELOW IN WIND SHELTERED AREAS. NORTHEAST WIND 15 TO 25 MPH DOWNTOWN. LIGHT WINDS ELSEWHERE. MONDAY...MOSTLY CLOUDY. HIGHS 20 TO 26. NORTHEAST WIND 15 TO 25 MPH. WIND GUSTS UP TO 40 MPH IN THE AFTERNOON NEAR DOWNTOWN With continued high winds over the last several days, most of the snow has been stripped out of the Urban avalanche paths. Although pockets of snow remain we now have large areas stripped to the ground. This discontinuous snowpack may have small areas of weakness but they are not large enough to pose a concern. The areas that are still holding snow have had quite a bit of wind deposited snow in them in some areas. This snow is quite hard in places. The exception to the rule here may be Chop Gulley. The avalanche path that comes down across the Flume Trail. There is still a little more mass in this area. Please avoid use of the flume trail. If you are in the backcountry today pay special attention to the spatial variability and note how one spot may be completely different from the next spot just 10 feet away due to wind affect. This will play a large role in our snow stability during the next several snowfall events. |
| Tip: | What makes a slab? When stronger snow overlies weaker snow, we call it a slab. Or as Karl Birkeland puts it, \"A slab is when you have something sitting on top of nothing.\" A slab can occur anywhere in the snowpack but avalanche professionals usually think of a slab as the layer that slides off the slope to create the avalanche. Remember that a slab doesn't have to be so hard that you can hardly kick you boot into it. It just has to be relatively stronger than the snow underneath. Light, dry powder snow can behave as a slab as long as it has an even weaker layer underneath. Most commonly, slabs tend to be harder, more cohesive snow such as wind slabs, denser new snow or settled old snow. |