Friday, May 15, 2015

Best Chances for Good Skiing

It may be deja vu all over again this weekend.  Alta-Collins has had 0.4" of water equivalent in the past 24 hours and will likely see some snow in fits and spurts today as well.  Then we have the potential for snow this weekend.

My approach when it comes to spring storms is to get out during or just following periods of significant snowfall.  If you wait too long, everything gets warm and manky, which not only results in poorer skiing, but also the potential for wet avalanches.

We spoke in the previous post (This NAM Forecast Is a Work of Art) about the dramatic comma-shaped character of the cloud and precipitation pattern for Saturday, as well as the pronounced dry slot.  Today's 1200 UTC NAM shows a similar pattern for 1500 UTC (0900 MDT) Saturday, with much of the area around Salt Lake City in the cyclonically wrapped dry slot, but precipitation just to our south.

Eventually the band of precipitation moves moves into northern Utah, but not until later in the day.

As such, my strategy for tomorrow may be one of patience.  If I get up and it's snowing and it looks like it will continue, I'll probably jump on it.  A bird in hand is worth two in the bush.  If it's not doing anything, I'll probably wait until late Saturday or early Sunday and hope the band comes through (the GFS is less optimistic about that band, but it's also been producing colossally terrible precipitation forecasts since it was upgraded this winter).    Given the convective nature of precipitation processes this time of year and the warm conditions, one needs to weigh the odds, but ultimately flexible.

One thing is for sure, this is likely to be another warm storm.  700 mb temperatures will be between -3 and 0ºC through noon Sunday (then they go even higher...all the more reason to get out early), which means wet snow and best accumulations above 9000 feet.  Total accumulations will probably be limited, in part by the high density.  The NAM is calling for about 0.6 inches of water at Alta-Collins from today at 6 AM through Sunday 6 AM, which translates to 5 inches of snow.  Something in the 4-8 inch range for that period is probably a best guess above 9000 feet.  Less below.

No comments:

Post a Comment