Dusty Past to be Buried

Just last Tuesday I expressed Optimism for the Corn Harvest this season with the hope that we might see more white corn this spring. 

No sooner said than on on Thursday I saw dust being reported in observations to the Utah Avalanche Center on Thursday.  I decided to have a look today while touring and lo' and behold there it was buried with the melt-freeze crust about 45 cm under the new snow from Thursday and Friday.  

We just can't catch a break. 

It's hard to say for sure where that dust came from.  I've looked over some of the PM2.5 data we have the the U and it's evolution relative to snowfall in the Wasatch and it's unclear.  It could have been during the strong southerly flow on Wednesday afternoon, but it's not a lock.  Sometimes the noise in the numbers makes conclusions difficult.  Perhaps others with eyeballs in the mountains have ideas.  

On the plus side, that dust layer is now buried.  If we don't add another layer with the strong flow today, maybe we can bury it further with the Sunday-Tuesday storm.  That storm is looking beastly right now.  The latest GFS shows snow-showers developing in the central Wasatch tonight,

continuing at times tomorrow, 

and then a strong frontal band developing over the area by Monday morning.

That and then pivots over the area as the upper-level trough moves inland over the Intermountain West during the day on Tuesday.

Then we get into a prolonged period of unstable, post-frontal snow showers for Tuesday afternoon.

Other models, like the Euro, are less excited about tomorrow's snowshowers, but like the GFS are bullish on the frontal band and post-frontal snowshowers.  

By 6 PM Tuesday our GFS-derived product for Little Cottonwood generates 3.5" of water and 50" of snow for Alta-Collins.  The often drier ECMWF HRES is around 2.25" of water.  The National Weather Service National Blend of Models, which is an ensemble comprised of a very large number of model runs, is putting out 2.68" of water and 27 inches of snow (the snow-to-liquid ratio for that product looks a little underdone).  Some snow may fall Tuesday night into Wednesday, although right now it looks like the bulk of the system will be through 6 PM Tuesday. 

I'd lean toward 2.25-3.5" of water and 30-48" of snow by 5 PM Tuesday.  

Buckle up.