Friday, March 2, 2012

Amazing Stuff Last Night

Oh to be in the mountains today enjoying the blower pow.  The Alta-Collins site recorded 15" of snow overnight, with about .83" of SWE, for a water content of about 5.5%.

Water contents that low usually require storms that are dominated by snow crystals with lots of air space, which means dendrites and lots of them.  You know what the dendrite is as it is the unofficial snowflake of Utah.  

One type of stellar dendrite (yes there are others).
The radar loop during the period of highest snowfall rates last night is fascinating.  Note how high radar reflectivities sit over the Stansbury, Oquirrh, and Wasatch Mountains.  This provides a nice example of how precipitation becomes enhanced by unstable flow over topography.  Meanwhile, there are some wind parallel bands that form at times, including over the Salt Lake Valley.  

The mechanisms responsible for those bands are unclear.  Several factors could contribute to their development including lake effect or terrain induced flows. 

I suspect there will be a lot of sick days taken today.  I'd be doing that, but I really do have a doctors appointment this morning.

Addendum @ 9:10 AM

Forgot to attach this panorama taken from the Avenues showing that winter has finally arrived along the Wasatch Front.  You might also notice the lingering orographic clouds over the Wasatch and Oquirrh Mountains.

Think you've got it good at Alta?  Measured snow depth at the Rocky Basin Snotel in the Oquirrh Mountains increased from 43 to 71" since yesterday afternoon.  That's 28" of new snow for those of you keeping track at home...

Addendum @ 9:20 AM

Some more photos taken through the grimy, reflective windows of my building, but check out the gorgeous wave clouds over the Wasatch (first photo) and the lingering, very shallow orographic snows falling in the Oquirrh Mountains (second photo).

1 comment:

  1. Dr. Jim,
    *3* Deep powder days this week by your standard and I didn't even get to ski a single one. As a graduate student some weeks are busy and some aren't so busy. I guess I just got a little unlucky. Going to have to fight the crowds on Saturday and Sunday.