THIS AVALANCHE ADVISORY EXPIRED ON March 5, 2020 @ 7:13 am
Avalanche Advisory published on March 4, 2020 @ 7:13 am
Issued by George Halcom - Payette Avalanche Center
bottom line

The Avalanche Hazard today is Low. Natural and Human triggered avalanches are unlikely today. Generally safe avalanche conditions exist, but watch for isolated areas of unstable snow, especially near ridges and cornices.

How to read the advisory


  • Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
Avalanche Problem 1: Normal Caution
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  • Likelihood ?
    Certain
    Very Likely
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  • Size ?
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The snow pack has gained a lot of strength, except for the surface of slopes tilted into the Sun where 1-2 inch crusts have formed and are not bonded that well to the snow below it.

As we see increasing temperatures through the next 48 hours, it is going to be a good idea to stay off, and out from under big slopes and cornices getting heated up by the Sun. Normal caution would include good backcountry travel protocols like not stacking more than one person in an avalanche path or slope steeper than 30 degrees, especially slopes that are getting Solar effect.

recent observations

Yesterday we toured the Lick Creek drainage just East of McCall. A little bit of fresh snow fell overnight from just a dusting around 5,000 feet to 1-2" in the 7-8,000 foot range. Solar crusts that are not stuck together were sometimes challenging on the skin track. We were able to sniff out some soft dry powder in the shady corners of Snowslide peak all the way down to about 6,000 feet where the warmer afternoon temperatures caused some involuntary braking at times. We observed some small loose activity from the Sun around 1pm on West aspects and slide paths.

Some small point releases around the rocks yesterday afternoon above Snowslide lake.

 

 

Sawtooth Peak shedding the fresh new snow in the form of rollerballs and point releases that looked like tracks in the path.

 

 

 

CURRENT CONDITIONS Today's Weather Observations From the Granite Weather Station at 7700 ft.:
0600 temperature: 24 deg. F.
Max. temperature in the last 24 hours: 32 deg. F.
Average wind direction during the last 24 hours: E
Average wind speed during the last 24 hours: 8 mph
Maximum wind gust in the last 24 hours: 25 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: NA inches
weather

 

Area Forecast Discussion
National Weather Service Boise ID
307 AM MST Wed Mar 4 2020

.SHORT TERM...Today through Friday night...A shortwave trough
passing through the ID panhandle today will keep clouds and a
chance of showers over the e-central Oregon and w-central Idaho
mountains. Otherwise dry and mild conditions will continue under
strong westerly flow aloft. Elevated terrain and portions of the
Snake Plain will be breezy again this afternoon, to include
Mountain Home and points east where gusts of 25 to 30 MPH are
possible. Flow backs to the southwest on Thursday as an upper
ridge amplifies over the interior NW. This will extend drier
conditions into the mountains and warm temperatures to near record
highs at some sites Thursday afternoon. The mild temperatures
will be accompanied by an easterly wind at lower elevations. The
ridge slides eastward on Friday in response to an approaching
trough. While still well above normal, high temperatures will be a
few degrees cooler across southeast Oregon with little change for
southwest Idaho zones. Clouds increase from west to east Friday
afternoon with light upslope precipitation developing in the
mountains Friday night as the trough edges closer. A summary of
potential record highs for Thur/Fri can be found in a PNSBOI
product.

.LONG TERM...Saturday through Wednesday...An upper-level trough
will move inland on Saturday, spreading precipitation across our
area. Snow levels 4000 to 5000 feet on Saturday will lower to the
valley floors on Sunday, but by then precipitation will have ended
at lower elevations. Scattered snow showers will continue over the
mountains through Tuesday as a second trough swings inland from
the Canadian coast. The outlook for Wednesday is still uncertain
due to model differences, but a low pressure system off the
California coast could circulate moisture far enough north for a
chance of mountain snow and valley rain showers in our area.
Temperatures will be around 10 degrees above normal on Saturday,
near normal Sunday and Monday, then slightly above normal Tuesday
and Wednesday.

&&

.AVIATION...VFR. BKN-OVC mid-level clouds over Baker County Oregon
and the central Idaho mountains, otherwise mostly clear. Surface
winds variable 10 kts or less, becoming west to northwest 10-20
kts after 18z. Winds aloft at 10k ft MSL west 30-40 kts.

 

Two-Day Mountain Weather Forecast Produced in partnership with the NOAA-NWS
McCall Airport at 5021 feet.
  Wednesday Wednesday Night Thursday
Weather: Mostly cloudy, with a high near 41. South wind 3 to 8 mph. Winds could gust as high as 21 mph. Partly cloudy, with a low around 19. Southwest wind 5 to 7 mph becoming calm in the evening. Mostly sunny, with a high near 48. Light east southeast wind becoming south southeast 5 to 10 mph in the afternoon.
Temperatures: 41 deg. F. 19 deg. F. 48 deg. F.
Wind direction: South SW ESE-SSE
Wind speed: 3-8 5-7 5-10
Expected snowfall: 0 in. 0 in. 0 in.
Granite Mountain at 7700 feet.
  Wednesday Wednesday Night Thursday
Weather: Isolated snow showers before 11am. Mostly cloudy, with a high near 28. Southwest wind 7 to 9 mph. Chance of precipitation is 20%. Partly cloudy, with a low around 25. Southwest wind 5 to 9 mph becoming south southeast after midnight. Mostly sunny, with a high near 37. South wind 10 to 16 mph.
Temperatures: 28 deg. F. 25 deg. F. 37 deg. F.
Wind direction: SW SW S
Wind speed: 7-9 5-9 10-16
Expected snowfall: 0 in. 0 in. 0 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.