The main low is spinning off the coast of Seattle this morning with lots of cold air depicted by the popcorn shaped clouds. When you see that it means there is really cold air over the ocean picking up moisture off the relatively warmer water. On the South side of the circulation a moisture streak is being pulled into Northern CA from a stationary low and area of moisture in the Central Pacific. This is adding moisture to the air that blowing in from the West this morning and is causing light snow showers on the mountain as the air is lifted.
This kind of snow will stay light through this morning bringing a couple of inches until the the moisture streak moves further South this afternoon and the snowfall becomes heavier. By tonight the cold moist flow off the Pacific will be in full force with heavy snow and then even heavier snow tomorrow as the cold front moves through. The heavy snow will last through the day on Friday before lightening Friday night as the storm shifts South. With the very cold air in place there could still be significant accumulation Friday night. Then on Saturday snow showers in the morning may give way to the sun poking through by afternoon, very similar to last Saturday.
Looking at the models this morning the GFS has caught up now with the other models with an average of 1.5-1.75 inches of total liquid by Saturyday. We will have snow ratios averaging 20:1 in the Village into Saturday and 25:1 or more above on the mountain especially on top at 8,600 ft.
I will break it down for you into 12 hour periods again like i like to do. In the Village: 3-6 today, 9-12 tonight, 9-12 tomorrow, 3-6 tomorrow night = 2-3 feet by Saturday. On the Mountain: 4-8 today, 14-18 tonight, 14-18 tomorrow, 4-8 tomorrow night = 3-4+ feet by Saturday. We will have to wait until Sunday morning for the final totals as the snowshowers linger into Saturday.
Storm train still lined up next week to bring us more storms starting Wednesday. More on that after we get through this storm. Was I too low in October on my prediction of 125% of average snowfall for Tahoe this season? BA