He expects about 2 to 5 inches in North Seattle, 1 to 3 inches in South Seattle, and 3 to 8 inches in northern Snohomish County.
Adding emphasis, he begins today's entry with:
Folks . . . this is serious. So serious that Ivar's is canceling my presentation tomorrow night at their Mukilteo Landing Restaurant . . . looks like we will try March 9th.
Here's a radar image of the storm. The green band in the middle is the "convergence zone." That's where the snow-making magic happens.
There's already snow in Everett and in Lake Stevens.
Further explaining what the average mortal cannot grasp, Mass continues:
There are a lot of subtlies [sic] in play here. First, the snow will be very banded, which means there will be a lot of horizontal structure (spatial variations in snowfall between neighboring locations). Second, for the early part of the period there will be significant rainshadowing (snow shadowing) off the Olympics under northwesterly flow . . . which means Kitsap and south Sound will have snow reduced. Third, a LOT of the action will be at the boundary between NE flow moving out of the Fraser and vicinity and southerly flow moving up the Sound. The southerly flow will be forced to rise by the cold, dense northerlies--producing enhanced precipitation (snow). That is why you see the heavy band between Seattle and Bellingham. No guarantees EXACTLY where that interface will lie. Upslope flow on the Olympics should produce heavy snow on the northern Olympic slopes.
But what does it all mean? The snow accumulation we mentioned earlier, of course. And as an added bonus he says that the temperature should remain warm enough to avoid any layers of solid ice.