THIS AVALANCHE ADVISORY EXPIRED ON March 13, 2019 @ 6:45 am
Avalanche Advisory published on March 12, 2019 @ 6:45 am
Issued by Melissa Hendrickson - Idaho Panhandle Avalanche Center

St. Regis Basin/Silver Valley

bottom line

A winter storm will deliver up to 14" of heavy snow by Wednesday morning.  Expect the avalanche danger to increase as the storm accumulates, hitting CONSIDERABLE by tomorrow. The main concern will be wind slabs on the N - E aspects.  Watch for storm slabs as well; this snow will be falling on crust on the W - E aspects from all the sun we recieved over the weekend and patches of surface hoar in sheltered areas on the N.

How to read the advisory

St. Regis Basin/Silver Valley

How to read the advisory

A winter storm will deliver up to 14" of heavy snow by Wednesday morning.  Expect the avalanche danger to increase as the storm accumulates, hitting CONSIDERABLE by tomorrow. The main concern will be wind slabs on the N - E aspects.  Watch for storm slabs as well; this snow will be falling on crust on the W - E aspects from all the sun we recieved over the weekend and patches of surface hoar in sheltered areas on the N.

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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After a few days of calm, we are back to strong SW-W winds with gusts in the 30s. These winds will easily transport the new snow into our typical loading zones on the N-E aspects.  Pay attention for smooth rounded, lens shaped pillows.  These will be chalky-white color and often sound hollow.  

Avalanche Problem 2: Storm Slab
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The high end predictions for the storm are up to 14" at the high elevations.  Expect this danger to increase as the storm goes on.  As of writing this forecast the storm has only begun, but is predicted for heavy snowfall through today and tonight. This snow is coming in on the warm side and will fall as a dense, cohesive layer.  On the north aspect, it will be falling on consolidating powder and sheltered patches of surface hoar.  On the E -S- W aspects, it will be falling on a melt-freeze crust from the past couple of sunny days.  As you are touring or riding, pay attention to the new snow to see how it is bonding to the older snow underneath.  This will change quickly by aspect and elevation, so make sure to stay on your toes.  

recent observations

Conditions have been excellent for the past couple of days, but expect them to change throughout the day and into tonight.  We are entering the day at Moderate/Low, but by the end of the storm it could reach CONSIDERABLE possibly even HIGH depending on how the totals come in.  There is a variety of bed surfaces for the snow to fall on, so stay vigilant in your observations and stay conservative as the storm progressess.  We are still in the March is a lion phase of the month.  (I'm not complaining).  Have a good, safe week.  

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: Snow Snow Showers likely then Chance Snow Showers Decreasing Clouds
Temperatures: 32 deg. F. 26 deg. F. 33 deg. F.
Wind Direction: SW SW SW
Wind Speed: 6-11 6-9, G18 6
Expected snowfall: 3-5 in. 1-3 in. 0 in.
For 4000 ft. to 6000 ft.
Tuesday Tuesday Night Wednesday
Weather: Heavy Snow and Breezy Heavy snow and Breezy Chance Snow Showers
Temperatures: 26 deg. F. 19 deg. F. 24 deg. F.
Wind Direction: SW W W
Wind Speed: 18-22, G31 16-24, G33 10-15
Expected snowfall: 3-7 in. 3-7 in. <.5 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.