The Cornice computer model works, in simple terms, on the basis of matching the daily data fed in with the nearest past matches of avalanche conditions from several years of records. Four close matches means that avalanche hazard conditions are considered likely. The model then uses what happened on these past occasions to forecast what might happen today/tomorrow.
The avalanche warning and forecast is then publicised on the SAIS website and by telephone request.
During the winter, SAIS staff and volunteers must feed the data into the computer model, based on the daily data they gather on:
- current meteorological and weather forecast data for the Cairngorms National Park, gathered from three automatic weather stations and the Meteorological Office;
- field observations of the weather and snow conditions, near the avalanche starting zones. In addition, a variety of field observations and measurements are made of snow/ice conditions from at least one snow pit.