Saturday, December 28, 2019

Major Is Relative

Yesterday I forecast that there would be no "major" storms in northern Utah the rest of the year, but some might be wondering what that means after the mess today in the central Wasatch. 

For that post, I was thinking of major accumulations.  Impacts, however, can be significant even with light snowfall amounts.

For example, snowfall this afternoon apparently made quite a mess in the Cottonwoods, with UDOT hoisting the "Traction Law" flag and the National Weather Service noting that things look "pretty dicey" not only in Little Cottonwood but also Parley's Canyon. 

The snowfall was produced by shallow cumulus clouds that were parked over the mountain ridges much of the day (e.g., see below).  I suspect a little surface heating from the sun, meager as it was, led to upslope flow and cumulus cloud initiation.  The precipitation-generating clouds were so localized and shallow that it was pretty much impossible to differentiate them from ground clutter in the radar imagery during the period. 

Source: NCAR/RAL
I haven't seen any snowfall reports from the lower canyons, but Alta-Collins reported only an inch in the late afternoon, although this is a situation where accumulations may have been greater at lower elevations.   Feel free to share your observations, but for goodness sakes, keep it clean. 

I haven't bothered going up into the Tri-Canyon area since in several days as part of my annual holiday-week exile.  It's not like the skiing elsewhere isn't good. 

With the low angle sun and decent snowpack, much is skiable right now.  Further, the nordic tracks are also skiing well.  We are indeed blessed this holiday season!


  1. A light, continuous snow fell pretty much all afternoon at Alta mid-mountain. Maybe 2 inches in spots. There were no reported slide-offs. Traffic backup was caused by huge crowds and everyone leaving Snowbird/Alta at once and going very slow due to snow pack on road. No plows were seen anywhere. Took me 4 hours on bus to get from Wildcat base to 94S 20E parknride. There were 8 buses backed up at Albion parking lot waiting to go down.

  2. I left Albion on the 3:29pm bus with an 11yo and 8yo in tow and it was snowing but not terribly hard; we got to Clif by 3:45pm but hit the wall there (it was 20min to get up to the stop sign and back onto the highway). Maybe an hour or so in, someone on the bus said the UTA app showed the 3:15pm bus ahead of us had already made it out of the canyon, so if true then conditions must have deteriorated quickly. It definitely snowed more heavily at the Bird- their parking lots were snowy and a mess as opposed to the Albion lot which still had blacktop showing when we left.

    Conditions weather and traffic wise had deteriorated further around Snowbird Center, which we got to at 4:52pm; I recall snowflake intensity and size being a fair bit greater there than both Albion and Clif. Got back onto the highway at 5:32pm. We saw a plow headed up canyon at one point, I think a ways above above Tanner's Flat. We got to the 94th/20th PnR by 6:20pm or so.

    Besides the hour in the Snowbird lots, I wonder what additional time we lost by having gotten out of line and getting stuck in the worse stuff. Speaking of which, most bus riders were from Snowbird, morning and evening, and it's not hard to see why. They dont have to make a bunch of extra stops so they are more willing to take the bus. When 44 mins to Albion is UTA's best time to run 10-12 miles, and it degenerates into a 3-4 hour descent on bad days, then we can never reasonably expect average persons to make self-interested decisions to take public transit regularly.