Avalanche Advisory published on March 22, 2019 @ 7:10 am
This Avalanche Advisory expires in 22 hours, 5 minutes
This advisory is valid for 24 hours
Issued by Dave Bingaman - Payette Avalanche Center
bottom line

The Avalanche Hazard is generally Low today. Loose wet avalanches are dependent on day time highs.  As temperatures climb avoid steep, rocky slopes that are getting the direct influence of the sun.  Rain in the forecast will likely increase the avalanche hazard in the next 48 hours. Cornices and cornice failure will also be something to consider as the snowpack warms or if it rains in the upper elevations.

How to read the advisory


  • Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
Avalanche Problem 1: Loose Wet
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Temperatures over the last week have been cool enough at night to allow the snowpack to refreeze giving us a great corn cycle this week.  Mid day temps have been in the upper 40's during the day and have produced loose/wet avalanches on slopes facing the sun.  Today  we are going to see a change in the weather as temps start to drop.  Partly cloudy skies and increasing clouds ahead of the next storm will likely keep the snow surface pretty solid today limiting the wet slide potential.

There is a chance that we could see some rain into the lower and middle elevations over the next 48 hours which will increase the free water in the snowpack loosening bonds and increasing the avalanche hazard.  In addition,  any new snowfall in the upper elevations will have a hard time sticking to the melt freeze crusts that have formed on nearly all aspects this week.  If the snow accumulates, anticipate that it will be moving on steeper slopes.

Avalanche Problem 2: Cornice
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We have not seen much in the way of large cornice failures yet, but sooner or later these monsters are going to start peeling off our ridgelines.  Avoid traveling close to the edges or under large cornices during the heat of the day or if rain falls in the upper elevations.  We have seen just a few big chunks coming off this week but it is a given that at some point in the next few weeks we are going to see some massive cornice falls.

 

advisory discussion

PAC will issue 3 Advisories per week through April 5. 

Your Observations are extremely helpful and appreciated by all backcountry users.  If you have not checked our our Observations page, it is really easy to add snow or avalanche info.  Drop down menus and prompts will lead you through it and it is easy to add photos.

Please be aware that there are areas that are CLOSED to motorized traffic in the McCall, Goose Lake and greater West Mountains area.  Just because there are tracks in some areas, does not mean they are open.  Please respect all users and closures.  See the Payette Winter Travel Maps for clarification.  Both the East and West maps can be downloaded on the Avenza app on your phone or are available at trailheads and local shops.   IT IS YOUR RESPONSIBILITY TO KNOW WHERE YOU ARE AND WHERE THESE CLOSURES EXIST. 

recent observations

Yesterday we toured above Duck Lake near Lick Creek Summit.  Hot sleds have been a problem in the mornings as the snow on and off trail is very firm even with scratchers down and frequent stops for cooling.  Light cloud cover delayed the softening of the snow surface until early afternoon and we were able to tour and ski some steep corn snow before it got too warm.  Surprisingly, the snowpack is not as saturated as we thought with only about 12 inches of wet snow above an older crust.  The snow below the crust was moist but not saturated or as wet as the snow closer to the surface.

Yesterday also looks like the last of the warm, sunny days for awhile and avalanche problems will shift from spring concerns back to more winter problems.  Rain above 6000 feet will likely saturate the upper snowpack creating the potential for larger, loose wet avalanches in the lower elevations.  The upper elevation snowpack is going to be locked up with a refreeze and the only hazard is going to be in the new snow/ crust interface. 

 

CURRENT CONDITIONS Today's Weather Observations From the Granite Weather Station at 7700 ft.:
0600 temperature: 33 deg. F.
Max. temperature in the last 24 hours: 45 deg. F.
Average wind direction during the last 24 hours: E
Average wind speed during the last 24 hours: 5 mph
Maximum wind gust in the last 24 hours: 17 mph
New snowfall in the last 24 hours: NA inches
Total snow depth: NA inches
weather

.SHORT TERM...Today through Monday...An upper level low will move
eastward away from the area today, while a stronger upper level
trough moves onshore in the PacNW. This stronger trough will
dominate our weather through the short term, bringing snow to the
mountains and rain to the valleys this weekend. McCall, for
example, will see rain initially, with precip changing to snow
Sunday afternoon. Temps will be above normal today, but fall below
normal Saturday and Sunday as the trough brings colder air to the
region. As the wave departs Sunday night and southwest flow ahead
of the next system brings warm air back into the area, temps will
rebound to above normal Monday. Precip will depart to the east
Sunday night and approach again in the west Monday.

.LONG TERM...Monday night through Thursday...Active weather
pattern will continue as the trough off the west coast brings
moist southwesterly flow into Wednesday. Expect scattered showers
across the forecast area. The upper level trough moves inland late
Wednesday into Thursday for increased coverage of showers along
with breezy conditions. Snow levels will fall from around 6000
feet Wednesday to about 4000 feet on Thursday. Showers will
continue behind the exiting trough Thursday night through Friday
under cold northwesterly flow. High and low temperatures begin
the period near normal but gradually cool down to a few degrees
below normal with the passage of the low.

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Today Tonight Saturday
Weather: Isolated showers after noon. Partly sunny, with a high near 49. Calm wind becoming southwest around 5 mph in the afternoon. Chance of precipitation is 20%. Showers likely, mainly after midnight. Mostly cloudy, with a low around 32. Light south southeast wind. Chance of precipitation is 60%. Showers likely. Cloudy, with a high near 44. Light and variable wind. Chance of precipitation is 70%.
Temperatures: 49 deg. F. 32 deg. F. 44 deg. F.
Wind direction: SW S Variable
Wind speed: 5 Light Light
Expected snowfall: 0 in. 0 in. 0 in.
Granite Mountain at 7700 feet.
  Today Tonight Saturday
Weather: Isolated snow showers after noon. Partly sunny, with a high near 38. Calm wind becoming southwest 5 to 7 mph in the afternoon. Chance of precipitation is 20%. Snow showers. Low around 26. Southwest wind around 6 mph becoming calm after midnight. Chance of precipitation is 80%. New snow accumulation of 1 to 2 inches possible. Snow showers. High near 33. Calm wind becoming north around 6 mph in the morning. Chance of precipitation is 80%. New snow accumulation of 1 to 2 inches possible.
Temperatures: 38 deg. F. 26 deg. F. 33 deg. F.
Wind direction: SW SW N
Wind speed: 5-7 6 6
Expected snowfall: 0 in. 1-2 in. 1-2 in.
Disclaimer

This avalanche advisory is provided through a partnership between the Payette National Forest and the Payette Avalanche Center. This advisory covers the West Central Mountains between Hard Butte on the north and Council Mountain on the south. This advisory applies only to backcountry areas outside established ski area boundaries. This advisory describes general avalanche conditions and local variations always occur. This advisory expires at midnight on the posted day unless otherwise noted. The information in this advisory is provided by the USDA Forest Service who is solely responsible for its content.

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