THIS AVALANCHE ADVISORY EXPIRED ON February 27, 2019 @ 6:50 am
Avalanche Advisory published on February 26, 2019 @ 6:50 am
Issued by Melissa Hendrickson - Idaho Panhandle Avalanche Center

St. Regis Basin/Silver Valley

bottom line

This cold weather keeps lingering around, as do the winds from directions that aren't our prevailing direction.  Over the past day we've seen winds from the E-SE and N, and they are supposed to be from the E - NE today and tomorrow. Heads up for wind slabs in the steep terrain below ridges, convex rollovers, and crossloading.  Avoid these areas by entering the slopes low in the sheltered timber.

How to read the advisory

St. Regis Basin/Silver Valley

How to read the advisory

This cold weather keeps lingering around, as do the winds from directions that aren't our prevailing direction.  Over the past day we've seen winds from the E-SE and N, and they are supposed to be from the E - NE today and tomorrow. Heads up for wind slabs in the steep terrain below ridges, convex rollovers, and crossloading.  Avoid these areas by entering the slopes low in the sheltered timber.

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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Small shots of snow and strong winds from the cold front are creating wind slabs on the westerly aspects.  The cold weather takes these longer to stabilize so give them a wide berth.  The cold temperatures for the next couple of days means that light fluffy snow will still be avaliable for transport, so expect to see wind slabs grow on the westerly aspects.  Look for shooting cracks and listen for whumping sounds when you are touring.  

Avalanche Problem 2: Persistent Slab
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This section should come as no surprise if you have been following the forecasts and it will not be going away in the next week with the cold temperatures that we are experiencing.  We are still finding rounding facets in the pack in most places.  Where this is a bigger problem is in areas with thinner snowpacks such as convex rollovers and steep ridges.  While the likelyhood keeps decreasing of triggering, the consequences are big if it is triggered.  

recent observations

The good and the bad.  There is more good in my opinion. While we might not be used to the cold temperatures and wind for such a long period of time, it is preserving our surface sliding conditions.  Small amounts of snow allow the pack to adjust and the stability to remain monderate. Unfortunately the cold does not help with solving our persistent weak layers.  It's easy to forget they are down there, but I'll be here on Friday morning to remind you of them again! In the meantime, send in some observations of what you are seeing out there!  Thanks to the NSP Level II Avalanche class at Silver for all the observations this weekend. 

Weather and CURRENT CONDITIONS
Two-Day Mountain Weather Forecast Produced in partnership with the Spokane NWS
For 2000 ft. to 4000 ft.
Tuesday Tuesday Night Wednesday
Weather: Slight chance snow then sunny Increasing clouds and blustery Snow likely
Temperatures: 20 deg. F. 11 deg. F. 26 deg. F.
Wind Direction: E NE NE
Wind Speed: 11-14 16-22 6-16
Expected snowfall: 0 in. 0 in. 1-3 in.
For 4000 ft. to 6000 ft.
Tuesday Tuesday Night Wednesday
Weather: Chance Snow and Patchy blowing snow then partly sunny mostly cloudy then snow likely and breezy Snow and patchy blowing snow
Temperatures: 9 deg. F. 2 deg. F. 17 deg. F.
Wind Direction: E E E
Wind Speed: 11-13, G21 14-20, G30 11-20, G31
Expected snowfall: <.5 in. <.5 in. 2-4 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.