The first half of this week will be unsettled with stormy weather and rising snow levels.
The first surge of moisture will come in Monday with a snow level of 4,500 ft. Expect a rain snow mix on the lower slopes. The snow level continues to rise late Monday into Tuesday as the firehose turns on.
An atmospheric river (see description below) will move in late Monday into Tuesday and early Wednesday with high snow levels (5,000 6,000 ft) with heavy rain on the mid and lower slopes. Skiing may be a bit messy. There will be a rain/snow mix on the upper slopes. Heavy rain will fall on the snowpack. The AR will not wipe out the snowpack. It may melt 10-20% from the lower slopes and certainly consolidate the pack. We are in good shape considering the current snowpack is above normal. The snowpack will recover to some degree as the AR weakens and exits on Wednesday (SL 3,500) with additional snowfall and a lowering snow level.
The total additional snow in the next three days will be difficult to estimate, given the changing snow levels and focus of the AR. This week, the weather takes away snow with rain melt then gives back with eventually lowering snow levels.
Id say by Wednesday we will pick up 5-10 new overall, but it could be twice as much at higher elevations or in the north Cascades. There are a lot of moving parts to this weather pattern.
Expect clearing on Thursday, then a weak storm on Friday. The upcoming weekend will see partial clearing.
Your Grand Poobah of Powder
Larry Schick - meteorologist