Utah Daily Snow

Summary

Snow will develop in Northern Utah late this afternoon into this evening with snow continuing overnight into Sunday. Our best accumulations so far this season with the highest amounts likely in the Cottonwoods. We generally clear out to start the week with only a weak, brush-by system. The end of October looks dry.

Short Term Forecast

Over the past 48 hours since my last forecast, I've been following the model trends and keeping close tabs on this storm.  The first weak storm on Thursday night did just as well as can be expected with up to 4 inches reported in the mountains.  This next storm, however, is much stronger. 

Yesterday, there was a trend in the Euro to weaken this system.  The euro has been the weaker model to begin with.  Other models such as the NAM and GFS have backed off slightly in amounts, but still have a healthy storm.  

In general, I'd expect most mountain areas to see 4-8" from this storm by midday Sunday.  The big exception could be the Cottonwood Canyons.  This storm has an extensive, moist northwesterly flow that could really work with the natural orographic lift that the Cottonwoods get (especially LCC).  Add to that the chance for lake enhancment from a warm GSL, and we have the potential for more significant amounts in the Cottonwoods. Here is the generally sensible 12km NAM graphical output for the Cottonwoods as of this morning: 

 

A healthy 8" of snow.  In these types of storms, I find that the 12km underdoes the orographical influences of the Cottonwoods.  In these instances, I will check the higher resolution 3km version of the same model.  In which case we get:

3 FEET of new snow!  Now let me say straight away that the 3km notoriously overdoes its amounts and I think it is VERY UNLIKELY that we get anywhere close to that much snow.  However, I post this because this is the type of storm where the Cottonwoods (especially LCC), could get a lot more snow than the 12km NAM suggests.  If you frequently ride LCC, then surely you've had one of those NW flow days where it just would not stop snowing in LCC.  Those days are somewhat hard to predict, as both NW flow and lake enhancement are wildcards that don't also perform as expected, but I think this storm has potential.  Something to watch.  

For those of you who like to see the storm totals on a map, here is a nice Northern Utah overlay that I made: 

You can see that the Cottonwoods are in the crosshairs.  Also, the Bear River range area up by Beaver Mountain could get hit hard.  This is likely the end of summer at Tony Grove Lake.  

We will be slow to clear out but precip should finish by Monday morning.  We will have a couple brush-by systems to start next week that could keep us cool with clouds, but overall we are done with big snow after the weekend.  

Extended Forecast

Still looks like we will be quiet to close out October.  I'm continuing to watch the forecast for a pattern change.  Hopefully we get some of the high pressure for the season out of the way now so that when it does start dumping, it doesn't stop! 

Evan | OpenSnow

P.S.  I forgot to include this earlier, but here is a GIF I made yesterday using Snowbird's new Roundshot cam that lets me compare archived images.  You can see the difference 24hrs makes from Thursday morning to Friday morning.  I'll get another image similar after this storm!