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Avalanche Forecast for 2019-12-02 07:00

  • EXPIRED ON December 3, 2019 @ 7:00 am
    Published on December 2, 2019 @ 7:00 am
  • Issued by Ryan Sorenson - Mount Shasta Avalanche Center

The avalanche danger is LOW at all elevations. Exercise normal caution. LOW avalanche danger does not mean NO avalanche danger. Small isolated wind slabs could remain on leeward slopes greater than 35 degrees. Evaluate snow and terrain carefully as you travel in the backcountry. 

Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

Avalanche Problem 1: Wind Slab

  • Character ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
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Small cornices and wind pillows were seen yesterday but were unreactive. Some uncertainty exits about above treeline conditions due to low visibility.  Wind speeds have been ideal for wind loading. Average wind speed has been 14 mi/hr in the last 24 hours on Gray Butte. 

Pay attention to where leeward areas reside. Stay away from steep slopes that have been loaded. Look for signs of the wind slab problem as you travel in safe terrain:

  • Shooting cracks, blocking, whumphing
  • Convex pillows of wind-drifted snow
  • Chalky, hollow sounding snow

Forecast Discussion

The snowpack is shallow and hazards could be lurking below snow surfaces. Ski and snowmobile cautiously. 

Giving Tuesday is December 3rd. Please donate! There will be a North State Giving Tuesday party from 6 p.m. to 8 p.m.  at the Shasta Mountain Guides storefront, 230 North Mount Shasta Blvd. , Mount Shasta.  You can also donate online at www.northstategives.org/FriendsOfTheMountShastaAvalancheCenter. Thank you!

 

Recent Observations

20191201 @ 1430 hrs -- Sorenson -- South side of Mt Shasta, below and near treeline during the storm

  • SKY: Obscured 100%, foggy, low visibility < .25 mile
  • PRECIP: Snowing lightly, < 1in/hr
  • BLOWING SNOW: yes, below treeline in isolated and exposed areas near treeline
  • AIR TEMP: 31 degrees F
  • SURFACE PEN: Boot: 8-14 inches. Soft unconsolidated snow atop supportable / Ski: 4-8". 
  • Height of Snowpack (HS):  22 inches at 6,800 feet (below treeline) / 27 inches at 7,900 feet (near treeline)
  • Height of New Snow (HN):  10 inches
  • Shallow snowpack many obstacles exits 

NOTES: Snow level near 5,500 feet and rising. Light to moderate winds were blowing out of the south/southeast and loading westerly aspects. Small drifts were observed up to 1 feet deep. These were unreactive to stomping. A quick pit dug near treeline found 10 inches of soft fist hard snow atop 15 inches of firmer snow below. Column tests yielded no notable or consistent failures.  Column test results: CTN

    

Weather and Current Conditions

Weather Summary

The winter storm currently impacting the Mount Shasta area is slowly moving south. Temperatures are expected to rise throughout the day. Precipitation will taper off this afternoon. Wind speeds are also expected to taper off. Mostly cloudy conditions today are expected to give way to mostly sunny conditions tomorrow. 

The next storm system is expected to arrive early Thursday morning. This storm has the potential to be very similar to the current storm with significant snowfall and low snow levels. 

24 Hour Weather Station Data @ 6:00 AM

Weather Station Temp (°F) Wind (mi/hr) Snow (in) Comments
Cur Min Max Avg Avg Max Gust Dir Depth New Water Equivalent Settlement
Mt. Shasta City (3540 ft) 33 31 33 32 0 N
Sand Flat (6750 ft) 33 25 33 30 25 2 0 2
Ski Bowl (7600 ft) 30 21 30 26.5 24.4 4.6 0 2.1
Gray Butte (8000 ft) 29.5 20.5 29.5 26 14 43 SSW
Castle Lake (5870 ft) 0 0 0 0 0 0 0 Not responding
Mount Eddy (6509 ft) 32 23.5 32 29.5 1 7 24.6 0 4.7
Ash Creek Bowl (7250 ft) down
Ash Creek Ridge (7895 ft) down

Two Day Mountain Weather Forecast

Produced in partnership with the Medford NWS

For 7000 ft to 9000 ft
  Monday
(4 a.m. to 10 p.m.)
Monday Night
(10 p.m. to 4 a.m.)
Tuesday
(4 a.m. to 10 p.m.)
Weather Mostly cloudy. Rain and Snow. Chance of precipitation is 90%. Snow level near 5700 feet. Mostly cloudy. Chance of precipitation is 30%. Snow level near 6800 feet. Mostly sunny. Slight chance of precipitation. Snow level near 6600 feet.
Temperature (°F) 36 30 37
Wind (mi/hr) South 5-10 Southeast 5-10 Southeast 5-10
Precipitation SWE / Snowfall (in) 0.29 / 2-4 0.07 / 0-1 0.03 / 0-0.50
For 9000 ft to 11000 ft
  Monday Monday Night Tuesday
Weather Cloudy. Snow showers likely. Chance of precipitation is 100% Mostly cloudy. Chance of precipitation is 30%. Mostly cloudy. Slight chance of precipitation.
Temperature (°F) 28 26 27
Wind (mi/hr) South 15-20 South 10-15 South 10-15
Precipitation SWE / Snowfall (in) 0.29 / 2-5 0.07 / 0-1 0.03 / 0-0.50

Season Precipitation for Mount Shasta City

Period Measured (in) Normal (in) Percent of Normal (%)
From Oct 1, 2023 (the wet season) 3.65 7.58 48
Month to Date (since Mar 1, 2024) 0.97 0.22 441
Year to Date (since Jan 1, 2024) 41.39 35.58 116

Disclaimer

This forecast does not apply to Ski Areas or Highways and is for the Mt. Shasta, Castle Lake and Mt. Eddy backcountry. Use this information for guidance only. You may find different conditions in the backcountry and should travel accordingly. This forecast expires on midnight of the date it was posted unless otherwise noted.