Valdez

Forecast Expired - 01/22/2023

Above 3,000ftModerate

1,500 to 3,000ftModerate

Below 1,500ftModerate

Degrees of Avalanche Danger

Avalanche Problems

Problem 1

Wet Avalanches:

Temperatures climbed to 40° F at seal level yesterday.  This prompted some large wet loose activity releasing from steep planar slopes on 1/20.  As temperatures remain elevated above the freezing mark, human triggered wet loose avalanches will be possible in steep terrain today.  Depending upon the size of the slope these can be dangerous, as they have the potential to entrain (gather) large amounts of snow that have the ability to knock a person off their feet or machine.  Terrain choice is very important with this avalanche problem.  When choosing an area to recreate imagine how much mass of wet loose snow is above you (size of slope) and what would happen if you were to be carried down hill (are there terrain traps?).  At upper elevations where the temperature is below freezing, top heavy storm slabs will exist 1-2 feet in depth.  These will be possible to trigger in steep terrain.

 

The hazard from this avalanche problem will slowly decrease as temperatures are forecasted to drop through the day.  Some large wet loose avalanches occurred on 1/20 with no step downs noted.  This points to strength in our mid snowpack.

Likelihood:

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

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Problem 2

Deep Slab:

Faceted snow at the base of our snowpack has not been reactive for 15 days, on 1/6 one outlier avalanche occurred at mid elevation near Thompson Pass (see avalanche activity section).  Prior to this, avalanches haven’t occurred since 12/16 at these deep layers.

 

 Rounding (strengthening) has been observed at these facets in all three forecast zones, but this process takes a lot of time.  At this point triggering an avalanche at this layer is unlikely.  Once significant snowfall returns to our area, expect for the potential to affect these deep layers to increase.  The most recent storm is not expected to be big enough to affect deep persistent layers.

 

Unlikely does not mean impossible, and triggering an avalanche deep in the snowpack would carry significant consequences.  The most likely place to affect these layers would be in thin, rocky areas in the Continental zone.  

 

 

Rounding facets near the base of our snowpack from Cracked Ice at 4000′ on 1/11.

Likelihood:

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

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Avalanche Activity

Below is a summary of observed Avalanche activity from the last 7 days.  Avalanches that were noted earlier in the season can be viewed by clicking the link below.

If you trigger or observe a natural avalanche consider leaving a  public observation.

Valdez Avalanche Activity

1/20- Numerous large (D2) wet loose avalanches released from steep planar slopes in the Port of Valdez.  These were caused by a foot or more of snow falling with temperatures rising to 40° F at sea level directly following.  No step downs noted.

 

1/17- Numerous wet loose point release were observed on solar aspects in the Port of Valdez.  Most of these originated from rocks were the suns energy permeated into dry snow and caused surface snow to become upside down.  No step down slab avalanches were observed.

 

-Small (D1) spin drift avalanches on the lee side of Tones Temple ridge triggered a small slab at the 1/14 BSH layer.

 

Weather

Check out our updated weather tab!  A collection of local weather stations are available for viewing with graphs and tabular data included.

NWS Watches and warnings

NONE
NWS Point forecast for Thompson Pass
Today
A 20 percent chance of snow before noon. Mostly cloudy, with a temperature falling to around 16 by 10am. North wind 25 to 30 mph.
Tonight
Mostly cloudy, with a low around 7. Northeast wind 25 to 30 mph decreasing to 15 to 20 mph after midnight.
Sunday
Snow likely, mainly between noon and 3pm. Cloudy, with a high near 26. East wind 5 to 10 mph. Chance of precipitation is 70%. New snow accumulation of less than a half inch possible.
Sunday Night
Snow. Low around 21. Northeast wind 5 to 15 mph becoming southeast after midnight. Chance of precipitation is 80%.
Monday
Snow. High near 30. Southeast wind 10 to 15 mph, with gusts as high as 20 mph. Chance of precipitation is 100%.
Monday Night
Snow. Low around 26. South wind around 15 mph, with gusts as high as 20 mph. Chance of precipitation is 90%.
Detailed forecast for Thompson Pass Mid elevation (2000-4000 Feet)
Date               Saturday 01/21/23       Sunday 01/22/23         
Time (LT)          06    12    18    00    06    12    18    00    06
Cloud Cover        OV    BK    OV    OV    OV    OV    OV    OV    OV
Cloud Cover (%)    75    65    70    70    90    95    95    95   100
Temperature        23    19    15     9    17    23    25    22    25
Max/Min Temp                   24           9          25          22
Wind Dir            N    NE    NE     E     E    SE     E     E    SE
Wind (mph)         16    19    16     6     6     8    12    12    10
Wind Gust (mph)                27                                    
Precip Prob (%)    20    10    30    20    50    70    70    70    80
Precip Type         S     S                 S     S     S     S     S
12 Hour QPF                  0.03        0.04        0.11        0.20
12 Hour Snow                  0.0         0.0         0.7         3.3
Snow Level (kft)  0.0   0.0   0.0   0.0   0.1   0.2   0.3   0.8   1.0
Click on link below for Thompson Pass weather history graph:

https://docs.google.com/spreadsheets/d/e/2PACX-1vR_Fl5087NrNCo2BtsSaum-gxrx1QioHSO4YqEmjW76LhuDu9ZsSxbBCTl6zkYIFarys-5eM_7P5GpV/pubhtml

 

 

 

Date:

01/21

24 hr snow HN24W* High temp Low temp 72 hour SWE* January snowfall Seasonal snowfall Snowpack Depth
Valdez 0 0 41 32 .69 39 136 54
Thompson pass  N/O N/O N/O N/O N/O 63 250 44
46 mile 8 .52 25 13 N/O 32 ~66** 42

 

 

*HN24W- 24 hour Snow water equivalent in inches

*SWESnow water equivalent

**46 mile seasonal snowfall total begins December 1st.

Additional Information

 

Click on the link below for a running summary of the seasons weather history.

Valdez Weather History

Announcements

The avalanche hazard is moderate at all elevations in the Port of Valdez.  Temperatures have climbed well above freezing at sea level, making it possible to trigger wet loose avalanches in steep terrain.  Avoid traveling in or above terrain traps.  The hazard will be decreasing as temperatures are forecasted to slowly decrease over the next 24 hours.

Posted by Gareth Brown 01/21  7:45 am.

 

For a description of current avalanche problems, weather information, season history and more click the (+ full forecast) button.  Avalanche forecasts will be issued Wednesday-Sunday.

If you have pictures of recent natural or human triggered avalanches or notice signs of instability such as shooting cracks or collapsing, leave an observation to help improve forecast accuracy.