December 17, 2016

    AVALANCHE ACTIVITY:

    No known avalanche activity reported in the area Friday

 
   YESTERDAY:

    Spectacular cold day Friday December 16, 2016.

    North wind Friday morning.

    A few clouds here and there.

    Snowmaking whiteness.

    Image from yesterday.

   Even with a very low relative humidity there is still some moisture in the air.

WEATHER OBSERVATIONS:

Weather Observations for December 17, 2016,: taken at 06:00 Hours.

2240 meters   -15, Winds were   5-10 KPH S   --Horstman Hut 
2180 meters   -16, Winds were   5-10 KPH W  --Whistler Peak
1860 meters   -15, Winds were 10-15 KPH SE --Rendevous
1835 meters   -14, Winds were    0-5 KPH E    --Roundhouse
1650 meters   -15, 0 cm of new snow, 0 cm in 24 hrs, 154 cm Base, RH 77%  --Pig Alley
1550 meters   -17, 0 cm of new snow, 0 cm in 24 hrs, 107 cm Base, RH 73%  --Catskinner 

  660 meters   -17, Valley Temp, Max Temp Yesterday was -10.5, 0.0 mm of Precip recorded yest

    As of 07:00 hrs this am we have clear skies and unlimited visibility.


FORECAST:

High pressure continues to dominate the pattern in a Northwesterly flow aloft. A series of troughs will push through the area over the next few days in a warmer Westerly flow. We should see an increase in cloud today as the low moves down the coast. Cloudy for Sunday with the brunt of the precipitation occurring at night. Periods of light snowfall Monday and Tuesday with another impulse of precipitation Wednesday night.  The freezing level will likely rise to almost 1000 meters on Monday but will fluctuate in a range to the valley bottom as well. The flow early next week will be fast so difficult to time the impulses of moisture. Windy conditions will also accompany the pattern over the next few days. Guesstimates: trace -2 cm for Sunday morning, 15-25 cm for Monday morning, 6-8 cm for Tuesday morning.

     IR Goes image this am.

    Cloudy Sunday with the FL slowly climbing back to valley btm.

    Upper level trough and occluded front for Monday.

   Wednesday night has the potential for a good dump!!



ARTICLES:

The Mystery of Glide Avalanches: ScienceNordic

How accurate is that Avalanche Advisory: Outside

Parameterizing surface wind speed over complex topography: Geophysical Research

Avalanche Warning: Colorado



   OBSERVATIONS:

Drew Lyness December 16 at 10:31pm

Skied N/ NW and SE aspects. Echoing reports from Wednesday, conditions are variable with some nice soft turns hiding between lots of thin windslab that remained unreactive, but seemed to be thickening at our turn around elevation of 2100m. Stuck to well supported terrain. Best guess at alpine temps: -20. Cold!

    Looks like clear ice.

    Snow making production is awesome!!

    Nice light Friday afternoon.

    Spindrift Friday afternoon--Max gust at 2240 m was 45 KPH, Max gust at 2135 m was 80 KPH.

    Some soft man made snow.