Valdez

Forecast as of 02/11/2019 at 06:00 and expires on 02/15/2019

Above 4,000ftNone

2,000 to 4,000ftNone

Below 2,000ftNone

The Avy Rose shows the forecasted danger by elevation and aspect.

It adds more detail about where you are likely to find the dangers mentioned in the forecast. The inner circle shows upper elevations (mountain top), the second circle is middle elevations, and the outer circle represents lower elevations.

Think of the Rose as a birds-eye view of a mountain, looking down from above. The rose allows our forecasters to visually show you which parts of the mountain they are most concerned about.

WNWNNEESESSW

Degrees of Avalanche Danger

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Avalanche Problems

Problem 1

Persistent Slab:

Likelihood:

  • Almost Certain
  • Very Likely
  • Likely
  • Possible
  • Unlikely

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Problem 2

Loose Snow:

Likelihood:

  • Almost Certain
  • Very Likely
  • Likely
  • Possible
  • Unlikely

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Problem 3

Glide Avalanches:

Likelihood:

  • Almost Certain
  • Very Likely
  • Likely
  • Possible
  • Unlikely

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Avalanche Activity

On Feb 6 numerous point releases from steep south and west aspects are observable around Valdez. There are no signs that these loose avalanches are stepping down into slabs.

On Feb 6 around Thompson Pass there were many point releases with no step downs or crowns.  A few specific observed point-releases are: N. Odyssey, Catchers Mitt, and Moonlight Basin.

A large slab avalanche has been easily observable in Benzene Alley, probably from Jan 29. There is up to 15' of debris. SS-N-R3~-D2.5-3 (ran 2000'~). Pictures on VAC Facebook page.

On Jan 30th multiple remote triggered and natural avalanches were observed between Nicks (gulley 3) and RFS. Crown heights were up to 4 FEET, above 3000' on north and south facing aspects. Reports continue to CONFIRM surface hoar was the weak layer, This layer is widespread and was buried on Jan 23.

Please share your field observations including signs of stable snow HERE.

Weather

The most recent NWS rec Forecast can be found HERE:

217 AM AKST Sat Feb 9 2019
The Thompson Pass Mountain Forecast covers the mountains (above
1000 ft) surrounding Keystone Canyon through Thompson Pass to
Worthington Glacier.
                   Today        Tonight
Temp at 1000`      32 F         25 F

Temp at 3000`      24 F         21 F

Chance of precip   0%           0%

Precip amount
(above 1000 FT)    0.00 in      0.00 in

Snow amount
(above 1000 FT)    0 in         0 in

Snow level         sea level    sea level

Wind 3000` ridges  LGT/VAR      LGT/VAR

Additional Information

SNOWPACK BIG PICTURE: The older snowpack is quite stable (good strength and structure). Any new snow since Jan 23 that HAS NOT AVALANCHED is likely to be sitting on widespread surface hoar and is current STILL UNSTABLE. Above 3500' there is up to 4' of new slabs sitting on this week layer.

Recent snowpack history, from top to bottom:

Feb 3-6: 0.7" SWE and 8" of snow from Valdez to Thompson Pass. 8" on new snow was recorded at 5500' on Catcher's Mitt. Freezing level was sea level throughout this cycle.

Jan 30-Feb 1: Natural avalanche cycle on all aspects above 3000', up to size D3. Most ran on buried surface hoar.

Jan 28-30: 2" SWE in Valdez, moderate winds, freezing level 1000'.

Jan 23-25: Multiple days of warm and wet with periods of rain up to 2500'.

Jan 13-22: Mostly clear and dry with light to moderate north winds. Widespread Surface Hoar growth and Near Surface Faceting.

Jan 12-13: 3-10" of new snow with little wind.

Jan 4-12: was VERY cold and dry: moderate winds and wind chill reaching -50F. Pockets of surface hoar and widespread near surface faceting.

Dec 30-Jan 3: The New Year's Eve storm brought nearly 2.5" of SWE to Valdez and almost another 1" (SWE) on the 2-3rd of January. The rain line was 1200' during the Jan 2-3 storm, forming a 1-3" crust locking up all the snow beneath it. These storms accumulated over 3' above 2000' near Thompson Pass. Both of these storms had little wind.

Above 4000' the snowpack averages well over 300cm deep and has good strength and structure (few lemons). Below 4000', the snowpack is significantly shallower and has old problem layers that are bonding well (rounding) and currently dormant: facet-crust combos and BASEL facets (all the way to sea level). 

 

If you get out riding, please send in an observation.

Do a rescue practice with your partners. Always carry a beacon, shovel, and probe, and KNOW HOW TO USE THEM. 

Practice good risk management, which means only expose one person at a time to slopes 30 degrees and steeper, make group communication and unanimous decision making a priority, and choose your terrain wisely: eliminating unnecessary exposure and planning out your safe zones and escape routes.

Announcements

There is no current hazard rating; but the most recent rating was MODERATE above 2000' because of a buried weak layer that has recently produced large avalanches.  Triggering these avalanches is becoming less likely; but the consequence will be the same: deep crowns, wide releases, 2 story debris piles, and long runouts. More info is available by clicking FULL FORECAST below. (All three forecast regions have the same info.)

Please share your field observations HERE