What are the Prospects for a Christmas Miracle?

Based on last night's SNOTEL observations, Snowbird sits at 6" of water (record low for December 20th at that site is 4.4"), Brighton 3.9" (record low 3.2"), Mill D North 3.7" (record low 2.0"), Thaynes Canyon 4.4" (record low 2.9").  

So, technically in the central Wasatch, we're not at record low levels, but we're also not far above those records and remain below a reasonable natural snowpack for proper skiing.

But is there hope of a Christmas Miracle?  

Through Christmas Eve day we'll continue to see warmth and some periods of low-to-mid elevation rain and mid-to-high elevation snow at times.  There's no "big" storm, but perhaps we can get add another 0.75–1.5" of water to the high elevation snowpack in Little Cottonwood from the bits and pieces through 5 PM MST on Christmas Eve.   

But what about the night before Christmas and Christmas?  Is there hope for a Christmas Miracle?

Well the GFS has a menacing trough off the west coast and a boatload of moisture moving into the western US at 2100 UTC 24 Dec (2 PM Christmas Eve).  

It's a slow moving trough, however, and is still off the coast by 1800 UTC 25 Dec (11 AM Christmas Day), so no cold air for Utah.

So, prospects for a white Christmas in the Salt Lake Valleys and other lowland areas of Utah are looking pretty grim.  The Utah Snow Ensemble plume for the Salt Lake City International airport shows some periods of precipitation late Christmas Eve and on Christmas, but the snow plume is flatlined through Christmas.  

Upper elevations may do better.  It's a warm storm, but notice the uptick in both water equivalent and snowfall at Alta-Collins that begins around 0000 Z 25 December (5 PM Christmas Eve).  

For what it's worth, the median 24-h water equivalent and snowfall forecast by the Utah Snow Ensemble for 5 PM Christmas Eve to 5 PM on Christmas at Alta-Collins are 0.87" and 6.9", equating to 12.5% water content Cascade Concrete.  I've spoken to Santa and he tells me that if you are nice and not naughty he will deliver more, possibly in the form of graupel.  If, however, you are naughty, he will bring less and push the snow level 9000 feet.  

Update on weather.utah.edu

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