How much does a change in elevation affect snowfall amounts? Specifically, if the snow level is low, let's say 500 feet, and 1 to 2 feet of snow is forecast for the passes, how much would likely fall at 2,000 feet?
Typically snow fall amounts do increase with altitude, and are lighter at lower altitudes or elevations. Typical computerized projections show this tendency over the Cascades and Olympics, however due to the complex nature of the terrain...there are often considerable variations. The steepness of the terrain and whether terrain (mountain slopes) are facing or somewhat sheltered from incoming moisture can complicate the picture considerably, making it difficult to make a sweeping generalization that is true in most or all cases. When our KING 5 Weather Center staff makes a snow forecast, it is based on a particular pattern expected over a single day.