You are here

Avalanche Advisory for 2018-03-11 06:40

  • EXPIRED ON March 12, 2018 @ 6:40 am
    Published on March 11, 2018 @ 6:40 am
  • Issued by Andrew Kiefer - Mt Shasta Avalanche Center
  • March 11, 2018 @ 6:40 am

    Advisory Hotline: (530) 926-9613

  • The avalanche danger is LOW for all elevations and NORMAL CAUTION is advised. Watch for falling rime ice in alpine terrain on Mount Shasta. Shallow snowpack hazards exist throughout the advisory area.

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

Avalanche Problem 1: Normal Caution

  • Character ?
  • Aspect/Elevation ?
  • Likelihood ?
    Very Likely
  • Size ?
    Very Large

Generally safe avalanche conditions exist in the backcountry. Continue to watch for isolated wind slabs above treeline. Look for places where small areas of drifting have occurred and firm layers of surface snow overlie softer layers. Often this will occur on the lee side of ridges, in terrain depressions, on convex terrain features and in the lee of isolated bands of trees.

Advisory Discussion

Strong solar radiation and warm temperatures will melt rime ice formations in upper elevation terrain on Mount Shasta today. Icefall is a significant concern. Be especially careful in Avalanche Gulch below Red Banks, the Trinity Chutes and Casaval Ridge. 

Recent Observations

Skies were partly sunny for most of the day yesterday with light and variable winds. Isolated rain and snow showers occurred late in the day and overnight with a trace amount of snow accumulating above 5,500 ft with light rain falling below. No avalanches or signs of instability have been observed for several days. Local observers found smooth skiing conditions in upper Avalanche Gulch yesterday. Areas of wind-affected snow were encountered as well as shallow snowpack hazards. High alpine rock features are covered in rime ice.

J. Coster Photo, Looking down Avalanche Gulch on 3/10/18

Weather and Current Conditions

Weather Summary

Today will be sunny with spring-like temperatures as a ridge of high pressure briefly develops overhead. Highs will be in the mid 40s to lower 50s with light S/SE winds. Things start to change tomorrow as a strong frontal system approaches from the west bringing warm and windy conditions.  A mix of rain and snow showers should begin in the afternoon with snow levels near 7,500 ft. Cool wet weather will continue through the week.

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) 29 28 58 40.5 1 N
Sand Flat (6750 ft) station down
Ski Bowl (7600 ft) 27.5 25 41.5 30.5 62 0 0 1
Grey Butte (8000 ft) 28 26 36 29.5 5 12 SSE
Castle Lake (5870 ft) 31.5 30 51 37.5 27 1 2
Mount Eddy (6509 ft) 27 24 40 32 2 7 WSW 42.9 1 0.5
Ash Creek Bowl (7250 ft) station down
Ash Creek Ridge (7895 ft) station down

Two Day Mountain Weather Forecast

Produced in partnership with the Medford NWS

For 7000 ft to 9000 ft
  Sunday Sunday Night Monday
Weather Sunny Mostly clear Partly cloudy with a chance of rain and snow
Temperatures 45 deg. F. 31 deg. F. 48 deg. F.
Wind direction SE E/SE E
Wind speed 0-5 mi/hr 5-10 mi/hr 10-15 mi/hr
Expected snowfall 0 in. 0 in. 0-.5 in.
For 9000 ft to 11000 ft
  Sunday Sunday Night Monday
Weather Sunny Mostly clear Partly cloudy with a chance of snow
Temperatures 26 deg. F. 26 deg. F. 27 deg. F.
Wind direction S S S
Wind speed 5-10 mi/hr 10-15 mi/hr 15-25 mi/hr
Expected snowfall 0 in. 0 in. 1-2 in.

Season Precipitation for Mount Shasta City

Period Measured Normal Percent of Normal
From Oct 1, 2017 (the wet season) 12.52 31.92 39
Month to Date (since Mar 1, 2018) 1.63 2.42 67
Year to Date (since Jan 1, 2018) 6.69 16.71 40


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