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Avalanche Advisory for 2018-02-16 05:10

  • EXPIRED ON February 17, 2018 @ 5:10 am
    Published on February 16, 2018 @ 5:10 am
  • Issued by Aaron Beverly - Mount Shasta Avalanche Center

Avalanche danger is LOW and NORMAL CAUTION is advised. Firm and icy snow surfaces are widespread and shallow snowpack hazards exist. Icefall and rockfall may be encountered above 11,000 ft on Mount Shasta.

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: Normal Caution

  • Character ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
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NORMAL CAUTION means:

  • Watch for isolated slabs.
  • Ski and ride one at a time in avalanche terrain.
  • Don't regroup in run out zones.
  • Basic avalanche rescue skills are essential in avalanche terrain.

Isolated slabs are related to wind and terrain. Look for places where small areas of drifting have occurred and firm layers of surface snow overlie softer layers. 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.

Forecast Discussion

Temperatures over the last 24 hours have remained near or below freezing keeping the snowpack on Mount Shasta unchanged. Even with warmer temperatures over the next couple of days, expect firm and icy snow surface conditions to continue. The trail from Bunny Flat is icy enough to cause a fall. Self-arrest on steep terrain will be difficult and must be immediate. Sharpen your crampons and ice axe and make sure you know how to use them if ascending above treeline.

Above 11,000 ft, always be prepared for falling rock and ice. Wear a helmet.

Avalanche danger is LOW at all elevations.

Recent Observations

In the last 24 hours, temperatures near treeline have ranged from 17-33 °F and easterly winds have been light.

The snowpack above 7,000 ft is 1-4 ft deep and comprised mostly of hard melt-freeze crusts and ice layers. Snow surfaces are firm and icy right out of the Bunny Flat parking lot. Coverage is spotty below treeline. Snow on the road to the Old Ski Bowl is thin but usable.

The upper Sand Flat road and cross-country ski trails are rough and firm. The lower road and trails are out of service.

The Castle Lake and Mount Eddy backcountry has 8 to 12 inches of snow but coverage is inconsistent and sparse. Winter recreation is limited.

No avalanches or evidence of unstable snow have been observed this month.

Weather and Current Conditions

Weather Summary

Warmer temperatures and mostly sunny skies will usher in the weekend. Saturday night a cold front moves in that may bring up to an inch of snow above 6000 ft by early Monday morning. Snow levels should drop down to town by late afternoon Sunday. Cold temperatures and mostly sunny skies will follow.

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) 28 28 51 37 5
Sand Flat (6750 ft) 26 26 31 29 19 0 0 0
Ski Bowl (7600 ft) 25 19.5 33 26.5 39.5 0 0 0
Gray Butte (8000 ft) 28 20.5 28.5 25.5 5 18 ESE
Castle Lake (5870 ft) 27 18 33.5 27 8 0 0
Mount Eddy (6509 ft) 28.5 18.5 32.5 28.5 2 9 SW 22.5 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
  Friday
(4 a.m. to 10 p.m.)
Friday Night
(10 p.m. to 4 a.m.)
Saturday
(4 a.m. to 10 p.m.)
Weather Sunny Partly cloudy A 30% chance of rain and snow after 4p.m. Mostly sunny. Little or no snow accumulation expected.
Temperature (°F) 44 30 46
Wind (mi/hr) NW 5-10 mi/hr NW 5-10 mi/hr NW 5-10 mi/hr
Precipitation SWE / Snowfall (in) / 0 / 0 / 0
For 9000 ft to 11000 ft
  Friday Friday Night Saturday
Weather Sunny. Windy. Wind chills near 10 deg F. Partly cloudy. Windy. Wind chills near 10 deg F. A 30 percent chance of snow after 4 p.m. Mostly sunny. Little or no snow accumulation expected.
Temperature (°F) 27 26 32
Wind (mi/hr) N 25-30 mi/hr N 0 W 25-30 mi/hr
Precipitation SWE / Snowfall (in) / 0 / 0 / 0

Season Precipitation for Mount Shasta City

Period Measured (in) Normal (in) Percent of Normal (%)
From Oct 1, 2023 (the wet season) 10.19 25.93 39
Month to Date (since Mar 1, 2024) 0.08 3.66 2
Year to Date (since Jan 1, 2024) 4.36 10.72 41

Disclaimer

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.