Wednesday, April 15, 2015

Snowbird Dumpage

This afternoon, some great micrometeorological magic has been blessing Snowbird, which is now reporting 36" of new snow.  Snowfall amounts appear to decrease as one moves further east.  Automated sensors at Alta-Collins show 24" and near the base of Supreme 17".  I've also heard reports of lesser amounts from ski tourers at Solitude, and of lesser amounts at the top of the Tram compared to lower on the mountain at Snowbird.  

I'm always hesitant to jump to conclusions based on automated sensors, so this discussion should be read with caution.  Nevertheless, the radar seems to support the view of a decline in snowfall from Little Cottonwood to Big Cottonwood to Park City.  Although this often occurs in NW flow, it's appears to be especially pronounced this afternoon.  To show this, I'll show a radar loop in which the high terrain around Little Cottonwood and the Park City ridge line are identifed with red lines.  

In the loop below, which begins at noon, note how the intensity and frequency of radar echoes is greatest around and northwest of Little Cottonwood Canyon.  Both the intensity and frequency decline as one moves northeastward into upper Big Cottonwood, and then even further as one goes across the Park City ridgeline and finally to Park City and the Snyderville Basin.  

One caveat to this analysis is that the radar is partially blocked along the radial that covers Big Cottonwood, so there is some tendency for less intense and frequent echoes there due solely to that reason.  Nevertheless, there does seem to be some signal here.  

With regards to the decline in snowfall near the top of the Tram, if legit, I suspect it reflects the shallow nature of the storm and considerable snow growth at mid elevations.  

Those of you skiing today should add some comments on what you observed.  


  1. Grizzly Gulch had about 18" at 6:30am. 10,200 in SilverFork had about 16", 8,700 had about 8". DaysForkhad 3' by 5pm. Skinning out intermeadiate was about 3' at top and Cardiff (south) might have had 40" or more...we had to use each others tracks to get any speed just to straightline and stop....goldilocks disappeared. Awesome:-)

    1. maybe I am imagining things but it looks like there is some heavy precip on the radar loop that just sits over cardiff and days, Way to pick an awesome tour plan!

  2. This evening at about 7 p.m. I'd say there was 25 inches on the Northeast slopes at the head of Days appreciable wind loading noted. Zero signs of instability.A real beauty!

  3. I talked to a couple of people in the Heber / Midway area that said they had no snow accumulation there. If so, that is a huge contrast in snowfall amounts.

  4. Impressive storm, but I think the 44" at the Bird were "inflated" a little. I just happened to be checking when they bumped their totals from 25 to 36" yesterday during the day. I checked Alta Collins and it had an erroneous reading that jumped from 7" to 16" in an hour that I'm guessing they used. Not sure where else they'd get their measurements from since they haven't been clearing the mid-mntn stake