THIS AVALANCHE ADVISORY EXPIRED ON March 28, 2018 @ 6:55 am
Avalanche Advisory published on March 27, 2018 @ 6:55 am
Issued by Melissa Hendrickson - Idaho Panhandle Avalanche Center

St. Regis Basin/Silver Valley

bottom line

It continues to still be winter up in the mountains! We have another storm hitting with 4 - 8 inches through tomorrow.  Accompanying that storm is sustained winds in the upper 20 mph range and gusts in the 40's.  Expect to find windloading on the leeward ridgetops and cross loading in open areas.  In the lower elevations where there is rain predicted with the storm, expect to see loose wet slides as the snowpack absorbs the rain.  

How to read the advisory

St. Regis Basin/Silver Valley

How to read the advisory

It continues to still be winter up in the mountains! We have another storm hitting with 4 - 8 inches through tomorrow.  Accompanying that storm is sustained winds in the upper 20 mph range and gusts in the 40's.  Expect to find windloading on the leeward ridgetops and cross loading in open areas.  In the lower elevations where there is rain predicted with the storm, expect to see loose wet slides as the snowpack absorbs the rain.  

2. Moderate

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

2. Moderate

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

1. Low

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Below Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
    Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
Avalanche Problem 1: Wind Slab
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Strong winds from the southwest and west will accompany the storm coming in. Expect windloading in the usual places at the higher elevations; steep slopes and ridgelines.  Expect crossloading in gullies that provide a subtle terrain change.  Pay particular attention to areas that have changed from logging since you rode in them last year, crossloading and windloading will have different patterns now. 

Avalanche Problem 2: Loose Wet
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The rain/snow line will rise with the storm causing the lower and mid elevation snowpack to become saturated.  Expect the danger for wet, loose slides to increase as the snow becomes heavier.  

Avalanche Problem 3: Persistent Slab
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The buried surface hoar layers from two weeks ago were still being reactive in north facing pits over the weekend.  It is important to check each location to test the stability of these layers before you commit to steeper, more exposed terrain.  

Weather and CURRENT CONDITIONS
Weather observations from the Region
0600 temperature: 27 deg. F.
Max. temperature in the last 24 hours: 27 deg. F.
Average wind direction during the last 24 hours: WSW
Average wind speed during the last 24 hours: 9 mph
Maximum wind gust in the last 24 hours: 20 mph
New snowfall in the last 24 hours: 2 inches
Total snow depth: 80 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Spokane NWS
For 2000 ft. to 4000 ft.
Tuesday Tuesday Night Wednesday
Weather: Rain/Snow likely then Showers likely and breezy Chance Showers then slight chance rain/snow Slight chance rain/snow then slight chance showers
Temperatures: 44 deg. F. 31 deg. F. 46 deg. F.
Wind Direction: SW SW SW
Wind Speed: 10-18 (G28) 7-16 (G24) 6-11
Expected snowfall: <.5 in. 0 in. 0 in.
For 4000 ft. to 6000 ft.
Tuesday Tuesday Night Wednesday
Weather: Snow Showers and windy Snow showers and windy then chance snow showers and breezy Slight chance snow showers
Temperatures: 34 deg. F. 27 deg. F. 35 deg. F.
Wind Direction: SW W W
Wind Speed: 25-30 (G43) 14-19 (G37) 11-15
Expected snowfall: 3-5 in. 1-3 in. 0 in.
Disclaimer

Avalanche conditions change for better or worse continually. Backcountry travelers should be prepared to assess current conditions for themselves, plan their routes of travel accordingly, and never travel alone. Backcountry travelers can reduce their exposure to avalanche hazards by utilizing timbered trails and ridge routes and by avoiding open and exposed terrain with slope angles of 30 degrees or more. Backcountry travelers should carry the necessary avalanche rescue equipment such as a shovel, avalanche probe or probe ski poles, a rescue beacon and a well-equipped first aid kit.  For a recorded version of the Avalanche Advisory call (208)765-7323.