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Avalanche Advisory for 2018-03-31 05:37

  • EXPIRED ON April 1, 2018 @ 5:37 am
    Published on March 31, 2018 @ 5:37 am
  • Issued by Nick Meyers - Shasta-Trinity National Forest

The avalanche danger is LOW at all elevations and aspects. Exercise normal caution. Watch for small, isolated wind slabs above treeline and loose wet activity near and below treeline. Be wary of falling rime ice on the upper mountain. 

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 ?
  • Likelihood ?
    Very Likely
  • Size ?
    Very Large

Generally safe avalanche conditions exist in the backcountry. LOW avalanche danger does not mean NO avalanche danger:

  • Watch for small isolated wind slabs where areas of drifting have occurred and firm layers of surface snow overlie softer layers.
  • Warm weather and solar radiation can cause loose wet avalanches. To avoid, travel when the snow surface is colder and stronger. Plan your trips to avoid crossing on or under very steep sunlit slopes.
  • Small cornices exist on easterly aspects. Increasing temperatures may weaken these causing them to fall. Avoid traveling on top or below them.

Advisory Discussion

Spring is the time of year when anything is possible: Warm, sunny days can be immediately followed by winter-like conditions: snow and avalanche danger, extreme wind, whiteout, cold temperatures. Climbing season is upon us. Plan and prepare properly. Every year, climbers become lost, injured or killed on Mount Shasta. While not an extremely difficult mountain, it still has real hazards. Don't get "casual day syndrome". Be honest with your skills and abilities. One poor decision can often snowball into a bad situation. Have fun, with safety in mind.
Temperatures will drop several degrees over the next couple days and winds will increase. This will keep loose wet snow instabilities at bay.

Recent Observations

Yesterday, high temperatures climbed to 55 deg F at treeline on Mount Shasta. In town, temps topped out at 70 degrees F. Winds have remained calm out of the W/NW. The several feet of snow from our late March storm(s) still continues its melt/freeze transition. Conditions yesterday in Avalanche Gulch were variable: icy ridge lines, some dryer wind effected snow and areas of melt/freeze, corn snow were encountered. Loose wet snow instabilities were far and few between. A thin layer of high cirrostratus clouds covered the sky for most of the day. Bunny Flat still holds a couple feet of snow. The Pilgrim Creek Sno-Park is likely compromised due to lack of snow. The Sand Flat cross-country ski trails are still fair game and in decent shape. Castle Lake area is marginal... a barely usable snowpack will allow for a few turns. The Eddy Mountains hold 3 to 4 feet of snow and a usable snowpack is available for skiers, but not really for snow machines.

Weather and Current Conditions

Weather Summary

An upper level short wave will swing through the area today. This could cause a bit more cloudiness, but overall, it will be another mild, spring day with temperatures just slightly lower than yesterday. Above treeline on the mountain, it may be a little breezy from the N/NW late this afternoon. A disturbance will dig southeastward Sunday and Monday. Easter will be dry here, albeit several degrees cooler. Drier air with high pressure moves in Monday afternoon with increasing sunshine. Models continue to be in agreement on an onshore flow with an active pattern of weak to moderate fronts for the second half of next week. Timing of these TBD! Have a great weekend.

24 Hour Weather Station Data @ 4:00 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) 38 38 70 52.5 2 N
Sand Flat (6750 ft) station down
Ski Bowl (7600 ft) 41.5 39 55.5 45 79.1 0 0 2.3
Gray Butte (8000 ft) 41 41 52.5 44.5 7 18 WNW
Castle Lake (5870 ft) 0 0 0 0 0 0 0 station down
Mount Eddy (6509 ft) 37.5 37 54 45 2 7 WSW 43.7 0 2.5
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
  Saturday Saturday Night Sunday
Weather Cloudy this morning, then clearing Mostly clear Sunny, then becoming partly cloudy
Temperature (°F) 52 33 48
Wind Direction NW NW NW
Wind Speed (mi/hr) 0-5 mi/hr 0-5 mi/hr 0-5 mi/hr
Expected Snowfall (in) 0 0 0
For 9000 ft to 11000 ft
  Saturday Saturday Night Sunday
Weather Cloudy this morning then clearing, breezy Mostly clear Sunny and windy, becoming partly cloudy
Temperature (°F) 31 30 30
Wind Direction W W W
Wind Speed (mi/hr) 15-20 mi/hr 15-20 mi/hr 15-20 mi/hr
Expected Snowfall (in) 0 0 0

Season Precipitation for Mount Shasta City

Period Measured (in) Normal (in) Percent of Normal (%)
From Oct 1, 2017 (the wet season) 15.95 35.33 45
Month to Date (since Oct 1, 2018) 5.06 5.83 87
Year to Date (since Jan 1, 2018) 10.12 20.12 50


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.