Tuesday, October 23, 2012

Location, Location, Location

With a narrow band of precipitation over northern Utah, it was all about location, location, location last night.  There was a remarkable contrast between the southern Wasatch Front, which got very little precipitation, and the northern Wasatch Front, which got pounded.  This shows up well in the radar loop below.


It is also apparent when looking at the radar-derived and gauge-measured storm-total precipitation analyses, which show nearly 2 inches of total precipitation in the Ogden-area mountains, but less than a half inch in the Cottonwoods.


I might add it was also colder to the north overnight.  Even at 0800 MDT this morning, it was 21ºF at Powder Mountain (8897 ft) compared with 30ºF at Alta-Collins (9662 ft).  The net result is that overnight the Cottonwoods saw very little snow, whereas the goods fell in the mountains to the north, as illustrated by the morning web cams.

Source: alta.com
Source: Powder Mountain
As we discussed yesterday, the Short-Range Ensemble Forecast (SREF) system hinted at the possibility that the Cottonwoods might be just south of the action overnight.  This was a case where the SREF proved to be quite helpful, since it helped illustrate where the larger-scale precipitation band was likely to be located.  On the other hand, I suspect it still understimated precipitation totals in the Ogden-area mountains.  At 16-km grid spacing, it simply cannot pick up on the orographic enhancement that occurs in that area.

2 comments:

  1. was it graupel up high too? are we setting up for a repeat of last year?

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  2. Absolutely nothing down in Utah county this morning. That Baroclinic zone stayed pretty far north. Was hoping for some rain or even snow this morning!

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