Item: Forecasting avalanches from atmospheric cross-5ections
Title: Forecasting avalanches from atmospheric cross-5ections
Proceedings: Proceedings of the 1998 International Snow Science Workshop, Sunriver, Oregon
Authors: Nicholas Logan
Abstract: The weather fashions both weak and strong snow layers. The weather forecast and snowpack data are key ingredients to an accurate avalanche forecast. Of these two elements, a precise mountain weather forecast is perhaps the most difficult to attain. Forecasters at the Colorado Avalanche Information Center use graphic cross-sections of the atmosphere to help forecast mountain weather and avalanche potential. This NOAA, National Weather Service product is compiled from balloon soundings and weather forecast models. It renders visual slices of the atmosphere above user-defined mountain locations. Seven of 39 weather parameters can be overlaid on the cross-section at one time. Four of these, wind velocity, wind direction, relative humidity and temperature are used for this study. The weather pattern at a specific site is forecast out 72 hours. This provides insight for the potential of weather-induced avalanches. Model output is examined for biases to help forecasters fine-tune their weather and avalanche predictions. Data from two weather stations are compared to a shared cross-section forecast during the winter of 1997-98.
Keywords: snow drifting, snow precipitation, avalanche forecasting
Digital Abstract Not Available