Most skiers typically expect that when it snows this much in the valley, it must be snowing a lot more in the mountains, but that is simply not the case so far today. On average during the month of November, Alta receives about 5 times as much precipitation as the Salt Lake City airport, but that's the average. Today, we're seeing very limited orographic enhancement of precipitation. For example, Alta-Collins has received only 1.17 inches of precipitation (snow-water equivalent) thusfar, or only 1.25 times more than Salt Lake City Airport.
Why is the enhancement so small? It's because the precipitation is being generated primarily by the front and typically the orographic enhancement of precipitation is smallest over the Wasatch Mountains during periods when large-scale processes, such as those associated with fronts, dominate the precipitation dynamics. For example, during the event below, which occurred during the 2001 Hundred Inch Storm, the ratio of precipitation (snow water equivalent) at Alta to Salt Lake City was lowest during the frontal storm stage [apologies for the poor resolution, but you are getting this for free :-)].
|Source: Steenburgh (2004)|