OK, so does it work?
As of mid April 04, I have had 43 days on Sasse Ridge to compare the real world with the model. General conclusion: considering all the wild assumptions on which the model is based, it seems to work fairly well.
It has been fairly good at predicting layers, and at what elevation they might peter out. On the other hand, on Dec. 3 and 4 2003 it missed the fact that 3 inches of new snow fell all the way to the valley floor, instead of turning to rain at ~3000 feet as the model suggested. This snow came from a very rapidly moving front with dropping temps on the backside. Hard to predict what the snow level will be in these conditions I think. There may also have been cold air pooling in the valley. Don’t really know.
On December 10 and 11 ‘03, the graph was surprisingly accurate, predicting the layers fairly well, as the total new, at least to 5400 ft. elv.
Dec. 17 and 18 ‘03 the model slightly underestimated the new snow on the valley floor, but otherwise seemed quite accurate, at least to 3900 feet. A monumental amount of new higher up. The model suggested that there would be a slight rain crust that would disappear between 3300 and 3800 feet, and excepting the valley floor data category, that’s just what I found. The model also quite accurately predicted how much new snow I would find at my usual campsite after one week.
The following week after 3 inches new snow higher up, but near freezing on the valley floor, the model did quite well at the difficult prediction of the new snow accumulation at lower elevations.
In any case, I am finding the graphs useful. They have been telling me how tough it’s going to be driving to the end of the road at least before the plow gets there, and how tough breaking trail is going to be. The newest graphs with temperature, solar radiation and wind speed have also been quite helpful. The temperature range may give a hint about whether or not a ‘layer’ shown on the graph is real, and the wind speed may give some indication of wind transport of snow.
Nov 2006: I still find the graphs quite useful. You do have to interpret them with caution however, and make sure that they are consistent with other sources of information.
Fall 2007: Yup, still using the graphs last winter, and the Sasse summer chart is handy for checking how the hiking conditions have been in the Cle Elum RD