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Avalanche Forecast for 2020-03-06 06:07

  • EXPIRED ON March 7, 2020 @ 6:07 am
    Published on March 6, 2020 @ 6:07 am
  • Issued by Nick Meyers - Shasta-Trinity National Forest

A winter weather advisory is in effect from 10PM this evening to 10AM PST Saturday above 3,500 feet.
Six to ten inches of new snow is forecast with strong southerly wind. Expect LOW avalanche danger today. MODERATE wind slab avalanche danger is possible by tomorrow morning. 

Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.

Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.

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

Avalanche Problem 1: Wind Slab

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

New, small to medium-sized wind slabs will be possible by tomorrow morning. The wind forecast indicates southwesterlies blowing 40-50 mi/hr above treeline. The heaviest precipitation is expected early Saturday morning. Should snow totals verify, plenty of fresh snow will be available for wind transport. Watch for newly formed wind slabs on primarily leeward N-NE-E facing slopes and other cross-loaded slopes. Signs like shooting cracks, blocking or cracking within new wind slabs is a sure sign to avoid this terrain and choose a safer line. 

Forecast Discussion

After weathering the driest month on record, is anyone even reading this still? Perhaps you are now with fresh snow on the horizon. A quick hitting storm will provide a much-needed refresh to our dirty, haggard snowpack. Good bonding between old and new snow layers is expected due to relatively warm temperatures, but still, lookout for those new wind slabs on steep slopes near/above treeline. Shred safe powder hounds!

Recent Observations

On Mount Shasta, existing snow surfaces leading into the storm are variable.  Below treeline, scalloped, dirty snow surfaces dominate with plenty of needles and tree debris littering the snowpack. Tree wells are fully exposed. Near treeline is transitional with smoother snow attained with elevation. Above treeline is a mixed bag of wind hammered snow, exposed rocks, dirt collection in depressions, sun cups and smooth areas as well. In the Castle Lake area, a sad and shallow snowpack exists.  Lake ice is untrustworthy. Check recent observation reports/photos for more details.

Weather and Current Conditions

Weather Summary

Mount Shasta is back in the winter game! A brief, but decent little storm will impact the area tonight/tomorrow. A frontal boundary is pushing in from the west today and expected to host moderate to locally heavy snowfall tonight for Bunny Flat and above. Snow levels today will be near 6,100 feet, but should lower to 5,700 feet tonight and 3,500 feet tomorrow. As much as .95" of water is forecast, which could mean a solid 6 to 12 inches of snow. The heaviest precipitation is expected between 10PM and 10AM overnight. South/Southwest wind will continue today, gradually fading into the weekend. High pressure will return Sunday.

24 Hour Weather Station Data @ 5:00 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) 47 30 63 52 2 N
Sand Flat (6750 ft) 34 32 49 39 37 0 0 0
Ski Bowl (7600 ft) 30.5 30.5 45 37.5 58 0 0 0.9
Gray Butte (8000 ft) 28 28 41.5 35 7 31 SW
Castle Lake (5870 ft) 35.5 35.5 55.5 43 25.3 0 0.6
Mount Eddy (6509 ft) 33.5 33.5 47 40 2 10 SSW 43.1 0 0.5
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
(4 a.m. to 10 p.m.)
Friday Night
(10 p.m. to 4 a.m.)
(4 a.m. to 10 p.m.)
Weather Mostly cloudy, slight chance of rain and snow this morning, then chance of snow after 4PM. Breezy. Snow level near 6,100 feet. Snow, mainly after 10PM. Snow heavy at times. Snow level near 5,700 feet. Snow before 10AM, then snow showers diminishing. Snow could be heavy at times. Snow level near 3,500 feet.
Temperature (°F) 40 23 29
Wind (mi/hr) South 10-15 South 10-15 Southwest 5-10
Precipitation SWE / Snowfall (in) 0.16 / 0-0.50 0.29 / 4-8 0.46 / 3-7
For 9000 ft to 11000 ft
  Friday Friday Night Saturday
Weather Slight chance of snow before 10AM, then snow likely after 4PM. Mostly cloudy, windy. Snow and windy. Snow before 10AM, then snow showers. Breezy
Temperature (°F) 24 12 12
Wind (mi/hr) South 30-40 South 30-40 Southwest 15-25
Precipitation SWE / Snowfall (in) 0.16 / 0-1 0.29 / 6-10 0.46 / 3-7

Season Precipitation for Mount Shasta City

Period Measured (in) Normal (in) Percent of Normal (%)
From Oct 1, 2023 (the wet season) 12.90 30.77 42
Month to Date (since May 1, 2024) 0 1.27 0
Year to Date (since Jan 1, 2024) 3.97 15.56 26


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 24 hours after the posted time unless otherwise noted.