You are here

Avalanche Advisory for 2018-01-17 06:16:41

  • EXPIRED ON January 18, 2018 @ 6:16 am
    Published on January 17, 2018 @ 6:16 am
  • Issued by Aaron Beverly - Mount Shasta Avalanche Center

Avalanche danger is LOW. Isolated wind slabs may be encountered on NE-E-SE aspects above 9,000 ft. Monitor changing conditions as a new storm moves in after 4 p.m.

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.

Forecast Hotline: (530) 926-9613

Avalanche Problem 1: Wind Slab

  • Character ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
    Large
    Small

It is unlikely you'll find wind slabs sensitive to human triggering, but look for them in isolated areas:

  • Near the tops of ridges
  • Rollovers above steep terrain
  • On NE-E-SE aspects
  • Above treeline

A wind slab avalanche today shouldn't be large enough to bury a person, but it could sweep you into undesirable terrain.

Forecast Discussion

Expect little change in the snowpack today and tonight. Tomorrow should bring several inches of snow at higher elevations. With moderate to strong winds expected, this will renew concerns for wind slabs. Monitor changing conditions over the next several days.

Falling rime ice and firm icy conditions remain a concern above treeline. Bring an ice axe, crampons, helmet, and the knowledge to use them if making a summit attempt. Snow sliders and riders will find favorable snow in gullies under 10,000 ft, but enough icy crusts are exposed to take one by surprise. Ski conservatively.

Recent Observations

Submit Snowpack Observations
Submit Avalanche Observations

Two to three inches of new snow Monday night freshened up the snowpack above 7000 ft. The height of new snow showed little variation with elevations up to 11,000 ft. Snow surfaces were a mix of wind drifts, firm icy crusts, and wind eroded features. Though a couple of small isolated wind slabs were encountered, none were sensitive to human triggering. New snow was well bonded with old snow. Overall the snowpack was stable.

Some fallen rime ice was encountered above 10,000 ft in Avalanche Gulch.

With no significant changes overnight, the snowpack should remain unchanged today until new precipitation begins after 4 p.m.

 

Weather and Current Conditions

Weather Summary

Everyone is talking about the parade of storms. Without overzealous optimism, here is the gist: 

  • Wednesday - Mostly dry conditions with increased winds as a warm front moves in. Some precipitation may begin after 4 p.m. Snow levels above 8000 ft.
  • Thursday - Blustery conditions with up to 1 in (2.54 cm) of water. Snow levels at 6500-7000 ft causing conditions to be wet below and near treeline. Above treeline, expect 4-8 in (15-20 cm) of snow.
  • Friday - In the morning, a cold front moves in bringing snow levels down to 5000 ft. About 0.1 in (.25 cm) of water and less than 1 in (2.54 cm) of snow is expected.
  • Saturday - Mostly cloudy with a trace amount of snow expected.
  • Sunday - One more burst of precipitation bringing close to an inch of water and several inches of snow at low elevations.

Always check the weather before you attempt to climb Mt Shasta. Further, monitor the weather as you climb. Becoming caught on the mountain in any type of weather can compromise life and limb. Be prepared.

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) 48 36 49 43 0 N
Sand Flat (6750 ft) 33 31 36 34 12 0 0 0
Ski Bowl (7600 ft) 34 27 34 32 26 0 0 0
Gray Butte (8000 ft) 31 27 32 30 7 25 W
Castle Lake (5870 ft) 38 33 39 37 0 0 0
Mount Eddy (6509 ft) 36 25 38 34 1 9 SSE 9 0 0
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
  Wednesday
(4 a.m. to 10 p.m.) 		Wednesday Night
(10 p.m. to 4 a.m.) 		Thursday
(4 a.m. to 10 p.m.)
Weather A 30 percent chance of rain, mainly after 4pm. Mostly cloudy. Breezy. Rain, mainly after 10pm. Windy. Chance of precipitation is 90%. Rain and snow, becoming all snow after 10am. Windy. Chance of precipitation is 100%.
Temperature (°F) 46 48 39
Wind (mi/hr) South 10-20 mph South 10-25 mph Southwest 15-20 mph
Precipitation SWE / Snowfall (in) / 0 / 0 / 3-7
For 9000 ft to 11000 ft
  Wednesday Wednesday Night Thursday
Weather A 30 percent chance of snow after 4pm. Mostly cloudy. Windy. Snow, mainly after 10pm. Windy. Chance of precipitation is 80%. Snow. The snow could be heavy at times. Wind chill values as low as -15. Windy. Chance of precipitation is 100%.
Temperature (°F) 35 25 25
Wind (mi/hr) Southwest 30-40 mph Southwest 0 Southwest 40-50 mph
Precipitation SWE / Snowfall (in) / 0 / 1 / 4-8

Season Precipitation for Mount Shasta City

Period Measured (in) Normal (in) Percent of Normal (%)
From Oct 1, 2024 (the wet season) 8.03 19.04 42.2
Month to Date (since Dec 1, 2024) 2.20 3.83 57.4
Year to Date (since Jan 1, 2024) 2.20 3.83 57.4

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.