November 16, 2014 Early Winter Update

Early Winter Bulletin, November 16, 2014     Issued/Updated: 9:00AM 11/19/14

While the lower elevations don’t have snow, our mountains above 2500 feet have a fledging winter snowpack.

DANGER TREND:   Avalanche danger is LOW. Danger will increase as the week’s snow and rain add layers and weight to our early season snowpack.

AVALANCHE PROBLEM(S):  

Problem Specific Travel Advisory – Coverage is thin at Thompson Pass. Wind has distributed the snow with many rocks shallowly buried.

Review your skills recognizing avalanche terrain, especially terrain traps. Practice companion rescue with your backcountry partners.

Unroped glacier travel isn’t a good idea – crevasse bridges are nonexistant or thin and weak.

List of Avalanche Problems <here>

AVALANCHE ACTIVITY:  Friday November 14 there was a temperature inversion. While the valleys remained cool, the upper elevations experienced above freezing temperatures. This triggered some loose snow avalanches out of rocky steep slopes to destructive size 2. Evidence of this was seen at the Pass and above town. In the upper start zones above the Shoup Trail, a few of these wet loose avalanche gouged to ground.

  • Avalanche sizing via destructive scale <here>
  • Avalanche size estimation aid <here>.

little odysseySNOWPACK DISCUSSION:  Thompson Pass area has an average snowpack depth of 15-20 inches. What snow has fallen so far this winter has been redistributed by both southerly and northerly wind. This has left variability in snow depth and surfaces. Low spots and gullies have up to 40 inches with soft powder on 20141115 Little Odysseytop. High ground is bare or shallow with a hard wind crust. Recent photo and snow profile from Little Odyssey.

Please CONTRIBUTE to the Snow Observations page <here>. This is your community avalanche page. Your photos and observations help others improve decision-making. Thank you.

 

 

 

WEATHER:   Expect a rain/snow mix Sunday night through Monday with minor accumulations above 2600 feet elevation. Temperatures hovering around freezing. South to southeast wind – moderate to strong at ridge tops.

Use links below to follow the up and coming weather.

SNOW & PRECIPITATION HISTORY:
VALDEZ
THOMPSON PASS
24 Hour Snow / Water Equiv.
0″ / 0.2″
1″ / 0.1″ 
November Snow / Water Equiv.
0″ / 1.7″
14″ / 1.6″
Current Snow Depth
0″
14″
Total Winter Snowfall
5″
66″
Total Winter Water Equivalent 2.9 7.7″
Snowload in Valdez 0 lbs / square foot

Our region is “one of the snowiest places on earth” says the recent weather detective climatologist investigation into the Serendipity / Rendezvous snowfall record set in 1963 <here>.

Weather Quicklinks:

  • NWS forecast for Northeast Prince William Sound <here>
  • NOAA NWS spot forecast for Thompson Pass <here>
  • Valdez Glacier UAF weather station at 6600 feet <data here> <map here>.
  • Thompson Pass weather <here>.
  • Further weather resources <here>

SNOW CLIMATE ZONES:

  • Maritime (Coastal) – from the Port of Valdez to Thompson Pass, all waters flowing into Valdez Arm and everything south of Marshall Pass.
  • Inter-mountain (Transitional) – between Thompson Pass and Rendezvous Lodge.
  • Continental (Interior) – the dry north side of the Chugach (north of 46 Mile, including the Tonsina River).
Elevations:
  • Alpine – Above 2,000 feet
  • Treeline – 2,000 feet
  • Below treeline – Below 2,000 feet

Getting stoked for winter? Come see Jeremy Jones’ new mountain movie HIGHER November 22 7pm Civic Center and WINTER PROJECT Alaskan snowmachine movie November 29 6pm Civic Center.

HIGHER posterwinter project flyer small web

 

 

 

 

 

 

 

 

Free smart phone avalanche forecasts at: http://www.avalancheforecasts.com/

Mid November 2014

Early Winter Bulletin, November 11, 2014     Issued/Updated: 9:00 AM 11/12/14

65 inches of snow has fallen at Thompson Pass, mostly during during October. A few small natural avalanches released in the upper elevations in early October followed with a few size 2 avalanches running with the foot of snow falling October 21-24. 

Elevations:
  • Alpine – Above 2,000 feet
  • Treeline – 2,000 feet
  • Below treeline – Below 2,000 feet

 

DANGER TREND:    The danger trend will remain steady for the foreseeable future with the danger confined to upper elevation gullies and lee slopes.

AVALANCHE PROBLEM(S):   Once wind drifted, even a few inches of snowfall can produce dangerous slab avalanches.

Wind-Slab iconWind Slab Avalanches: Where exposed to winds in the upper elevations, the few feet of snow on the ground at has drifted to many feet deep.

Problem Specific Travel Advisory – Monitor the snow conditions, particularly where the snow has been drifted into soft and hard slabs. Review your skills recognizing avalanche terrain, especially terrain traps, and rescue skills.

Unroped glacier travel isn’t a good idea in the early winter as the crevasse bridges are thin and weak.

List of Avalanche Problems <here>

AVALANCHE ACTIVITY:      New snow instabilities with little mass with the Veterans Day warming.

  • Avalanche sizing via destructive scale <here>
  • Avalanche size estimation aid <here>.

SNOWPACK DISCUSSION:   Notwithstanding the huge system in the Bering Sea Nov 6-10, little precipitation made it onshore bringing only 7 inches of snow to Thompson Pass.

Please CONTRIBUTE to the Snow Observations page <here>. Your photos and observations are welcome and helpful for all to stay in tune with the current conditions. Thank you.

WEATHER:   Dry until 6 inches possible Monday November 17.

Use links below to follow the up and coming weather.

SNOW & PRECIPITATION HISTORY:
VALDEZ
THOMPSON PASS
24 Hour Snow / Water Equiv.
?” / ?”
1″ / 0.1″
November Snow / Water Equiv.
?” / ?”
13″ / 1.4″
Current Snow Depth
?”
15″
Total Winter Snowfall
?”
65″
Total Winter Water Equivalent  7.5″
 Snowload

Weather Quicklinks:

  • NOAA NWS spot forecast for Thompson Pass <here>
  • Valdez Glacier UAF weather station at 6600 feet <data here> <map here>.
  • Thompson Pass weather <here>.
  • Further weather resources <here>

SNOW CLIMATE ZONES:

  • Maritime (Coastal) – from the Port of Valdez to Thompson Pass, all waters flowing into Valdez Arm and everything south of Marshall Pass.
  • Inter-mountain (Transitional) – between Thompson Pass and Rendezvous Lodge.
  • Continental (Interior) – the dry north side of the Chugach (north of 46 Mile, including the Tonsina River).

2015 is the tenth year of public avalanche safety bulletins for the Valdez Chugach mountains October through May

Free smart phone avalanche forecasts at: http://www.avalancheforecasts.com/

Early November 2014

Early Winter Bulletin, October 30, 2014     Issued/Updated: 9:00 AM 11/3/14

Five feet of snow fell at Thompson Pass during October. A few small (generally < size 2) natural avalanches released in the upper elevations October 6-10 followed with a few size 2 avalanches running with the foot of snow falling October 21-24. 

Elevations:
  • Alpine – Above 2,000 feet
  • Treeline – 2,000 feet
  • Below treeline – Below 2,000 feet

 

DANGER TREND:    The danger trend will remain steady for the foreseeable future with the danger confined to mid and upper elevation gullies and lee slopes.

AVALANCHE PROBLEM(S):   Once wind drifted, even a few inches of snowfall can produce dangerous slab avalanches.

Wind-Slab iconWind Slab Avalanches: Although there is only an average of only a foot of snowpack on the ground at Thompson Pass after the warming October 11-13, and the winds at the end of the month, the snow exposed to the outflow winds in the upper elevations has drifted to many feet deep.

Problem Specific Travel Advisory – Monitor the snow conditions, particularly where the new snow has been drifted into soft and hard slabs. Review your skills recognizing avalanche terrain, especially terrain traps, and rescue skills.

Unroped glacier travel isn’t a good idea in the early winter. The crevasse bridges are thin and weak.

List of Avalanche Problems <here>

AVALANCHE ACTIVITY:   Of interest is the size 2 avalanche which released on October 24 off the big slope at the top of the mountain above the Shoup Bay trail, likely triggered with a combination of warm temperatures in the upper elevation, direct solar radiation and a foot of new snow. Temperatures dropped dramatically into the single digits on the 27th confining any new activity to windslabs built with strong outflow winds.

  • Avalanche sizing via destructive scale <here>
  • Avalanche size estimation aid <here>.

SNOWPACK DISCUSSION:   The storm of October 4-5 deposited three feet of snow at Thompson Pass. Another foot of snow accumulated October 9-10 followed with a foot of snowfall accumulating October 21-24 and a few inches on the 30th.

Please CONTRIBUTE to the Snow Observations page <here>. Your photos and observations are welcome and helpful for all to stay in tune with the current conditions. Thank you.

WEATHER:   Generally overcast with precipitation for the foreseeable future. Superstorm <here> and <here> where we can expect 18 inches to accumulate above the freezing level by November 9th and maybe a total of five feet by mid-month. Daily NOAA NWS freezing level prediction in spot forecast <here>.

Use links below to follow the up and coming weather.

SNOW & PRECIPITATION HISTORY:
VALDEZ
THOMPSON PASS
24 Hour Snow / Water Equiv.
?” / ?”
5″ / 0.6″
November Snow / Water Equiv.
?” / ?”
6″ / 6.7″
Current Snow Depth
?”
13″
Total Winter Snowfall
?”
58″
Snowload

Weather Quicklinks:

  • NOAA NWS spot forecast for Thompson Pass <here>
  • Valdez Glacier UAF weather station at 6600 feet <data here> <map here>.
  • Thompson Pass weather <here>.
  • Further weather resources <here>

SNOW CLIMATE ZONES:

  • Maritime (Coastal) – from the Port of Valdez to Thompson Pass, all waters flowing into Valdez Arm and everything south of Marshall Pass.
  • Inter-mountain (Transitional) – between Thompson Pass and Rendezvous Lodge.
  • Continental (Interior) – the dry north side of the Chugach (north of 46 Mile, including the Tonsina River).

2015 is the tenth year of public avalanche safety bulletins for the Valdez Chugach mountains October through May

Free smart phone avalanche forecasts at: http://www.avalancheforecasts.com/

Mid-October 2014

Early Winter Bulletin, October 10, 2014     Issued/Updated: 9:00 AM 10/10/14

Four feet of new snow has produced the season’s first avalanches. Early winter avalanches have killed unsuspecting mountain travelers, including a hiker out of Girdwood in November of 1997.

Elevations:
  • Alpine – Above 2,000 feet
  • Treeline – 2,000 feet
  • Below treeline – Below 2,000 feet

 

DANGER TREND:  The danger trend will remain steady for the foreseeable future with the danger confined to mid and upper elevation gullies and lee slopes.

AVALANCHE PROBLEM(S):   Once wind drifted, even a few inches of snowfall can produce dangerous slab avalanches.

Wind-Slab iconWind Slab Avalanches: The new snow has drifted to thigh deep above 2500 feet elevation producing both new snow avalanches and slab avalanches.

Problem Specific Travel Advisory – Monitor the snow conditions, particularly where the new snow has been drifted into soft and hard slabs. Review your skills recognizing avalanche terrain, especially terrain traps, and rescue skills.

Unroped glacier travel isn’t a good idea in the early winter as the crevasses are not covered.

List of Avalanche Problems <here>

AVALANCHE ACTIVITY: Wet snow point release avalanches to destructive size 2 released to ground in the upper elevations on Friday October 10.

A few soft slab avalanches to destructive size 1+ were observed on Monday October 6th in the mid and upper elevations in the inter-mountain (transitional) snow climate zone off lee slopes and gully walls releasing with strong north winds.

  • Avalanche sizing via destructive scale <here>
  • Avalanche size estimation aid <here>.

SNOWPACK DISCUSSION:  The storm of October 4-5 deposited up to three feet of snow. Another foot of snow accumulated October 9-10.

Please CONTRIBUTE to the Snow Observations page <here>. Your photos and observations are welcome and helpful for all to stay in tune with the current conditions. Thank you.

WEATHER: Expect another foot of snow to accumulate over the weekend above the freezing level after which the skies will slowly clear through the following week.

Use links below to follow the up and coming weather.

SNOW & PRECIPITATION HISTORY:
VALDEZ
THOMPSON PASS
24 Hour Snow / Water Equiv.
?” / ?”
4″ / 0.75″
October Snow / Water Equiv.
?” / ?”
40″ / 3″
Current Snow Depth
?”
16″
Total Winter Snowfall
?”
40″

Weather Quicklinks:

  • NOAA NWS spot forecast for Thompson Pass <here>
  • Valdez Glacier UAF weather station at 6600 feet <data here> <map here>.
  • Thompson Pass weather <here>.
  • Further weather resources <here>

SNOW CLIMATE ZONES:

  • Maritime (Coastal) – from the Port of Valdez to Thompson Pass, all waters flowing into Valdez Arm and everything south of Marshall Pass.
  • Inter-mountain (Transitional) – between Thompson Pass and Rendezvous Lodge.
  • Continental (Interior) – the dry north side of the Chugach (north of 46 Mile, including the Tonsina River).

2014 marks the ninth year of public avalanche safety bulletins for the Valdez Chugach mountains October through May

Free smart phone avalanche forecasts at: http://www.avalancheforecasts.com/

October 2014

Early Winter Bulletin, October 7, 2014     Issued/Updated: 9:00 AM 10/7/14

Wind drifted new snow has produced the season’s first avalanches. Early winter avalanches have killed unsuspecting mountain travelers, including a hiker out of Girdwood in November of 1997.

Elevations:
  • Alpine – Above 2,000 feet
  • Treeline – 2,000 feet
  • Below treeline – Below 2,000 feet

 

DANGER TREND:  The danger trend will remain steady for the foreseeable future with the danger confined to mid and upper elevation gullies and lee slopes.

AVALANCHE PROBLEM(S):   Once wind drifted, even a few inches of snowfall can produce dangerous slab avalanches.

Wind-Slab iconWind Slab Avalanches: The new snow has drifted to thigh deep above 2500 feet elevation and cornices have failed triggering small avalanches.

Problem Specific Travel Advisory – Monitor the snow conditions, particularly where the new snow has been drifted into soft and hard slabs. Review your skills recognizing avalanche terrain, especially terrain traps, and rescue skills.

List of Avalanche Problems <here>

AVALANCHE ACTIVITY:  A few soft slab avalanches to destructive size 1+ were observed on Monday October 6th off lee slopes and gully walls releasing with wind loading as the north winds moved in as the weekend’s storm ended.

  • Avalanche sizing via destructive scale <here>
  • Avalanche size estimation aid <here>.

SNOWPACK DISCUSSION:  The storm of October 4-5 deposited up to three feet of new snow marking the beginning of winter.

Please CONTRIBUTE to the Snow Observations page <here>. Your photos and observations are welcome and helpful for all to stay in tune with the current conditions. Thank you.

WEATHER: The next significant storm is forecast to move onshore Friday evening and persist through the weekend of October 11-12. Two inches of rain may accumulate at sea level and two feet of snow may accumulate above the freezing level which may reach 3-400 feet elevation Saturday night or Sunday.

Use links below to follow the up and coming weather.

SNOW & PRECIPITATION HISTORY:
VALDEZ
THOMPSON PASS
24 Hour Snow / Water Equiv.
?” / ?”
trace” / 0.01″
October Snow / Water Equiv.
?” / ?”
28″ / 2″
Current Snow Depth
?”
16″
Total Winter Snowfall
?”
28″

Weather Quicklinks:

  • Valdez Glacier UAF weather station at 6600 feet <data here> <map here>.
  • Thompson Pass weather <here>.
  • Further weather resources <here>

SNOW CLIMATE ZONES:

  • Maritime (Coastal) – from the Port of Valdez to Thompson Pass, all waters flowing into Valdez Arm and everything south of Marshall Pass.
  • Inter-mountain (Transitional) – between Thompson Pass and Rendezvous Lodge.
  • Continental (Interior) – the dry north side of the Chugach (north of 46 Mile, including the Tonsina River).

2014 marks the ninth year of public avalanche safety bulletins for the Valdez Chugach mountains October through May

Free smart phone avalanche forecasts at: http://www.avalancheforecasts.com/

Season Final Bulletin, May 13, 2014

Final Spring Bulletin, May 13, 2014     Issued/Updated: 9:00 AM 5/13/14

This is the last bulletin for the 2013-2014 season. It is a quick synopsis of typical spring conditions and how to manage them. Avalanche hazards still remain, so combine the info here and your personal experience to create safe strategies for spring travel in the mountains. Celebrate surviving another winter by soaking up some sun and fun.

Elevations:
  • Alpine – Above 2,000 feet
  • Treeline – 2,000 feet
  • Below treeline – Below 2,000 feet

 

DANGER TREND:  The danger trend will remain steady for the foreseeable future; avalanche danger is less each morning and increases through the day – especially warm, sunny days.

AVALANCHE PROBLEM(S):   As warm, sunny days continue to prevail and summer nears, a variety of new and old avalanche problems can reveal themselves. Wet snow avalanches, deep persistent slab releases and cornice/icefall failure will occur independently or as part of a chain reaction.

icon-wet avalanches

Loose Wet & Wet Slab Avalanches: Wet sluffs continue to initiate around warming rock bands and entrain larger amounts of snow, eventually down to ground. These point releases and/or failing cornices will also trigger larger slab avalanches down to weak layers or the ground. (See avalanche activity below.) Monitor the sun-baked slopes for wet, loose snow and slab sensitivity during these warm days.

 

Problem Specific Travel Advisory – Timing is everything. Plan your outing according to which aspects and elevations are loosing strength. Keep in mind that you don’t want to be stuck in steep terrain when the snow is acting more like water. Use the morning conditions as a timing gauge: the warmer the night-time temperatures, the quicker the snow will degrade that day. Limit exposure to overhead hazards: cornices, couloirs, rock bands etc.

List of Avalanche Problems <here>

GENERAL TRAVEL ADVISORY: 

  • Travel on glaciers requires the gear and skills for crevasse rescue.
  • Snow bridges are sagging and opening up.

AVALANCHE ACTIVITY:  New avalanches to destructive size 2+, continue to initiate in warming rocky areas and on steep north facing faces. While most of these are loose snow releases from solar effect, some slabs have been pulling out naturally on steep, northerly coastal mountain faces around 3,000 ft. The slabs, seen from a distance, have similarities to a human triggered slab from Sunday May 4 on the Pass. These slabs are likely sliding on the Damalanche facet interface, before gouging down to ground in thinner spots. With warm, sunny weather ahead, look out for more of this activity.

  • Avalanche sizing via destructive scale <here>
  • Avalanche size estimation aid <here>.

SNOWPACK DISCUSSION:  With the last warm and sunny period, we have seen that the facets above the Damalanche crust are still a problem in places. Several slides since May 3rd have been large wet slabs running on the crust or just above. Other shallower areas have gouged down directly to the ground-vegetation.

If we get another winter-like storm (not impossible for May), analyze the interface between it and the old surfaces. A storm slab, especially in the high elevations, might just take the first sun to cause activity.

As the snow becomes more isothermal at the upper elevations and until firn snow forms, consider the ability to trigger avalanches down to deep to weak layers or even the ground.

Please CONTRIBUTE to the Snow Observations page <here>.

Photos and observations are welcome and helpful for all to stay in tune with the current conditions. Thanks!

WEATHER: A high pressure ridge will linger over us and provide more sun and warmth through the 3rd week of May. Overnight freezes will lesson and raise in elevation, making for a weaker snowpack. Use links below to follow the up and coming weather.

SNOW & PRECIPITATION HISTORY:
VALDEZ
THOMPSON PASS
24 Hour Snow / Water Equiv.
?” / ?”
0″ / 0.01″
May Snow / Water Equiv.
?” / ?”
0″ / 0.3″
Current Snow Depth
?”
20″
Total Winter Snowfall
?”
335″
(Valdez NWS office has permanently closed=no new data)
MAY 1st SNOW SURVEY:
Location: Depth: Inches of Water: Percent Water:
Valdez 15 5 32%
Milepost 18 20 8 38%
Worthington Glacier 53 20 37%
Milepost 37 31 10 33%

Weather Quicklinks:

  • Valdez Glacier UAF weather station at 6600 feet <data here> <map here>.
  • Thompson Pass weather <here>.
  • Further weather resources <here>
  • Summary of January 13-30 avalanche cycle<here>
  • Season Summary from the beginning of winter to January 8 <here>

SNOW CLIMATE ZONES:

  • Maritime (Coastal) – from the Port of Valdez to Thompson Pass, all waters flowing into Valdez Arm and everything south of Marshall Pass.
  • Inter-mountain (Transitional) – between Thompson Pass and Rendezvous Lodge.
  • Continental (Interior) – the dry north side of the Chugach (north of 46 Mile, including the Tonsina River).

2014 marks the ninth year of public avalanche safety bulletins for the Valdez Chugach mountains October through May

Free smart phone avalanche forecasts at: http://www.avalancheforecasts.com/

Saturday-Tuesday, May 10-May 13, 2014

Saturday-Tuesday, May 10-May 13, 2014     Issued/Updated: 8:00 AM 5/10/14

AVALANCHE DANGER RATING:

SATURDAY:     SUNDAY:     MONDAY & TUESDAY:
Morning: Afternoon:   Morning: Afternoon:   Morning: Afternoon:
Above 3,000′ Above 3,000′ Above 3,000′ Above 3,000′ Above 3,000′ Above 3,000′
high icon high icon high icon
Below 3,000′ Below 3,000′ Below 3,000′ Below 3,000′ Below 3,000′ Below 3,000′
high icon high icon high icon

DANGER SCALE details <here> explain the colors and symbols.

Elevations:
  • Alpine – Above 2,000 feet
  • Treeline – 2,000 feet
  • Below treeline – Below 2,000 feet

 

FORECASTER CONFIDENCE: GOOD

DANGER TREND:  The danger trend will remain steady over for the next few days, meaning low each morning and increase each afternoon with warm, sunny days. Temperatures will remain above freezing overnight at the mid elevations.

AVALANCHE PROBLEM(S):  A variety of new and old avalanche problems can reveal themselves during the spring thaw. Wet snow avalanches, deep persistent slab releases and cornice/icefall failure can occur independently or as part of a chain reaction.

icon-wet avalanches

Loose Wet & Wet Slab Avalanches: Solar warming problems have returned. Watch out for wet sluffs off of warming rock bands and failing cornices. Monitor the sun-baked slopes for wet slab sensitivity with these warm days.

Problem Specific Travel Advisory – Limit exposure and travel earlier before the snow gets too soft and saturated with water. Timing is everything.

List of Avalanche Problems <here>

GENERAL TRAVEL ADVISORY: 

  • Travel on glaciers requires the gear and skills for crevasse rescue.
  • Snow bridges are sagging and opening up.

AVALANCHE ACTIVITY:  New avalanches, size 2 to 2+, continue to occur with a scattering of size 3. Most of them are initiating naturally off of solar heated rocks, while one size 3 was human triggered Sunday May 4 on the lower face below Python at about 3,000′. Several of the natural point releases have pulled in adjacent wet slabs, likely sliding on the Damalanche facet interface, before gouging down to ground in thinner spots. With warm, sunny weather ahead, look out for more of this activity.

Human triggered slide on Sun, May 4

20140504_171524[1]L

  • Avalanche sizing via destructive scale <here>
  • Avalanche size estimation aid <here>.

SNOWPACK DISCUSSION:  With the last warm and sunny period, we have seen that the facets above the Damalanche crust can promote a problem. Many slides have used the heavy, wet snow above this weak layer to pull in more snow via wet slabs to create larger events. Other shallower areas have directly gouged down to the depth hoar at the ground-vegetation.  Additionally, consider the increasing temperatures and solar effect as the warm days stick around into next week.

New snow transport could be seen off the summits yesterday, so if you are headed up to the higher peaks, look out for pockets of wind slab near ridge tops. Most old surfaces are hard and won’t play well with new snow util it is given time. On the other hand, north aspects could have preserved dry snow underneath, but look out for near-surface facets that could be buried.

Snow below treeline is melting fast and isothermal. Many aspects at the mid elevations that get a lot of solar radiation are not far behind.

Please CONTRIBUTE to the Snow Observations page <here>.

Photos and observations are welcome and helpful for all to stay in tune with the current conditions. Thanks!

WEATHER: A high pressure ridge will provide more sun and warmth through the weekend. Some clouds may start to settle in Tuesday as the low pressure in the Gulf of Alaska extends out to reach us. Overnight temperatures have returned to above freezing at Thompson Pass.

WEATHER FORECAST for TODAY @ 5,000 ft (RIDGETOP):
Temperature Forecast (deg F): Mid-High 30’s
Ridgetop Wind Forecast (mph): NNE @ 7
Snowfall Expected Next 24 Hrs: 0
SNOW & PRECIPITATION HISTORY:
VALDEZ
THOMPSON PASS
24 Hour Snow / Water Equiv.
?” / ?”
0″ / 0.01″
May Snow / Water Equiv.
?” / ?”
0″ / 0.3″
Current Snow Depth
?”
20″
Total Winter Snowfall
?”
335″
(Valdez NWS office has permanently closed=no new data)
WIND & TEMPERATURE HISTORY (Past 24 Hours) : VALDEZ AIRPORT THOMPSON PASS
Average Wind Speed (mph) / Direction 13 / ENE 33 / NE
Max Wind Gust (mph) 40 43
Temperature Min / Max (deg F) 45 / 64 40 / 49

 

MAY 1st SNOW SURVEY:
Location: Depth: Inches of Water: Percent Water:
Valdez 15 5 32%
Milepost 18 20 8 38%
Worthington Glacier 53 20 37%
Milepost 37 31 10 33%

Weather Quicklinks:

  • Valdez Glacier UAF weather station at 6600 feet <data here> <map here>.
  • Thompson Pass weather <here>.
  • Further weather resources <here>
  • Summary of January 13-30 avalanche cycle<here>
  • Season Summary from the beginning of winter to January 8 <here>

SNOW CLIMATE ZONES:

  • Maritime (Coastal) – from the Port of Valdez to Thompson Pass, all waters flowing into Valdez Arm and everything south of Marshall Pass.
  • Inter-mountain (Transitional) – between Thompson Pass and Rendezvous Lodge.
  • Continental (Interior) – the dry north side of the Chugach (north of 46 Mile, including the Tonsina River).

2014 marks the ninth year of public avalanche safety bulletins for the Valdez Chugach mountains October through May

Free smart phone avalanche forecasts at: http://www.avalancheforecasts.com/

Thursday-Sunday, May 8-May 11, 2014

Thursday-Sunday, May 8-May 11, 2014     Issued/Updated: 7:30 AM 5/8/14

AVALANCHE DANGER RATING:

THURSDAY:     FRIDAY:     SATURDAY & SUNDAY:
Morning: Afternoon:   Morning: Afternoon:   Morning: Afternoon:
Above 3,000′ Above 3,000′ Above 3,000′ Above 3,000′ Above 3,000′ Above 3,000′
Moderate-150x150 high icon high icon high icon
Below 3,000′ Below 3,000′ Below 3,000′ Below 3,000′ Below 3,000′ Below 3,000′
Moderate-150x150 Considerable Considerable Considerable

DANGER SCALE details <here> explain the colors and symbols.

Elevations:
  • Alpine – Above 2,000 feet
  • Treeline – 2,000 feet
  • Below treeline – Below 2,000 feet

 

FORECASTER CONFIDENCE: GOOD

DANGER TREND:  The danger is increasing since a reasonable amount of new precipitation has and continues to fall in our forecast area. New rain and/or snow adds weight and stress to an already weakened snowpack after last weeks warm days and little overnight freezing. Snow at the higher elevations will be resting on very firm layers that will not bond immediately. Once the sun shows itself again and/or temperatures rise significantly, be concerned about a series of new avalanches to occur. With the temperatures and precipitation dropping, the daily trend should return to the cycle of lower hazard with nighttime freezing and higher hazard with afternoon warming.

AVALANCHE PROBLEM(S):  A variety of new and old avalanche problems can reveal themselves during the spring thaw. Wet snow avalanches, deep persistent slab releases and cornice/icefall failure can occur independently or as part of a chain reaction.

icon-wet avalanches

Loose Wet & Wet Slab Avalanches: The snow has had a series of warm days to progressively weaken it with limited freezing at night. New rain and/or snow will only add stress despite recent temperatures closer to freezing at night. Solar warming will likely be a problem when the sun shows itself again Thursday or Friday.

Problem Specific Travel Advisory – Be cautious just after a heavy rain-snow event. Let things settle. As days begin to warm again, plan your activity with the daily warming in mind.

List of Avalanche Problems <here>

GENERAL TRAVEL ADVISORY: 

  • Travel on glaciers requires the gear and skills for crevasse rescue.
  • Snow bridges are weakening.

AVALANCHE ACTIVITY:  Many new size 2 to 2+ avalanches have occurred since April 29th with a scattering of size 3. Most of them seem natural, while one size 3 was human triggered Sunday on the lower face below Python at about 3,000′. Most all seem to be starting as point releases, then branch out by pulling wet slabs, sliding on the Damalanche facet interface, before trenching down to ground in thinner spots. These all seem to have happened during the sunny, warm spell.

20140504_171524[1]

  • Avalanche sizing via destructive scale <here>
  • Avalanche size estimation aid <here>.

SNOWPACK DISCUSSION:  With the last warm and sunny period, we have seen that the facets above the Damalanche crust can promote a problem. Many slides have used the heavy, wet snow above this weak layer to pull in more snow via wet slabs to create larger events. Other shallower areas have directly trenched down to the depth hoar at the ground-vegetation.  Keep an eye out for natural activity with added rain and weight to the snowpack. This will only add more lubricant to the weak layers that a slab could slide on. Additionally, consider the increasing temperatures and solar effect as the days warm and skies clear later in the week.

Any new snow that falls at the higher elevations should be inspected to see how it is bonding with the old surfaces below. Most old surfaces are hard and won’t play well with new snow util it is given time. On the other hand, north aspects could have preserved dry snow underneath, but look out for near-surface facets that could be buried.

Snow below treeline is melting fast and isothermal. Many aspects at the mid elevations that get a lot of solar radiation are not far behind.

Please CONTRIBUTE to the Snow Observations page <here>.

Photos and observations are welcome and helpful for all to stay in tune with the current conditions. Thanks!

WEATHER: After a brief break in weather yesterday, overcast skies and rain have pushed back in. It looks like it should start to break Thursday evening, while Friday and onward into the weekend are still looking quite nice and sunny. Overnight temperatures have continued to be closer to freezing at Thompson Pass, but slightly warmer last night. That means rain on the pass and snow line higher up.

WEATHER FORECAST for TODAY @ 5,000 ft (RIDGETOP):
Temperature Forecast (deg F): 36
Ridgetop Wind Forecast (mph): NE @ 10
Snowfall Expected Next 24 Hrs: 0
SNOW & PRECIPITATION HISTORY:
VALDEZ
THOMPSON PASS
24 Hour Snow / Water Equiv.
?” / ?”
0″ / 0.01″
May Snow / Water Equiv.
?” / ?”
0″ / 0.3″
Current Snow Depth
?”
27″
Total Winter Snowfall
?”
335″
(Valdez NWS office has permanently closed=no new data)
WIND & TEMPERATURE HISTORY (Past 24 Hours) : VALDEZ AIRPORT THOMPSON PASS
Average Wind Speed (mph) / Direction 5 / SW 7 / SW
Max Wind Gust (mph) 12 13
Temperature Min / Max (deg F) 39 / 54 31 / 43

 

MAY 1st SNOW SURVEY:
Location: Depth: Inches of Water: Percent Water:
Valdez 15 5 32%
Milepost 18 20 8 38%
Worthington Glacier 53 20 37%
Milepost 37 31 10 33%

Weather Quicklinks:

  • Valdez Glacier UAF weather station at 6600 feet <data here> <map here>.
  • Thompson Pass weather <here>.
  • Further weather resources <here>
  • Summary of January 13-30 avalanche cycle<here>
  • Season Summary from the beginning of winter to January 8 <here>

SNOW CLIMATE ZONES:

  • Maritime (Coastal) – from the Port of Valdez to Thompson Pass, all waters flowing into Valdez Arm and everything south of Marshall Pass.
  • Inter-mountain (Transitional) – between Thompson Pass and Rendezvous Lodge.
  • Continental (Interior) – the dry north side of the Chugach (north of 46 Mile, including the Tonsina River).

2014 marks the ninth year of public avalanche safety bulletins for the Valdez Chugach mountains October through May

Free smart phone avalanche forecasts at: http://www.avalancheforecasts.com/

Wednesday to Saturday, May 7-10, 2014

Wednesday-Saturday, May 7-May 10, 2014     Issued/Updated: 7:30 AM 5/7/14

AVALANCHE DANGER RATING:

WEDNESDAY:     THURSDAY:     FRIDAY & SATURDAY:
Morning: Afternoon:   Morning: Afternoon:   Morning: Afternoon:
Above 3,000′ Above 3,000′ Above 3,000′ Above 3,000′ Above 3,000′ Above 3,000′
Moderate-150x150 high icon high icon high icon
Below 3,000′ Below 3,000′ Below 3,000′ Below 3,000′ Below 3,000′ Below 3,000′
Moderate-150x150 Considerable Considerable Considerable

DANGER SCALE details <here> explain the colors and symbols.

Elevations:
  • Alpine – Above 2,000 feet
  • Treeline – 2,000 feet
  • Below treeline – Below 2,000 feet

 

FORECASTER CONFIDENCE: GOOD

DANGER TREND:  The danger is increasing since a reasonable amount of new precipitation has fallen in our forecast area. New rain and/or snow adds weight and stress to an already weakened snowpack after last weeks warm days and little overnight freezing. Snow at the higher elevations will be resting on very firm layers that will not bond immediately. Once the sun shows itself again and/or temperatures rise significantly, be concerned about a series of new avalanches to occur. With the temperatures and precipitation dropping, the daily trend should return to the cycle of lower hazard with nighttime freezing and higher hazard with afternoon warming.

AVALANCHE PROBLEM(S):  A variety of new and old avalanche problems can reveal themselves during the spring thaw. Wet snow avalanches, deep persistent slab releases and cornice/icefall failure can occur independently or as part of a chain reaction.

icon-wet avalanches

Loose Wet & Wet Slab Avalanches: The snow has had a series of warm days to progressively weaken it with limited freezing at night. New rain and/or snow will only add stress despite recent temperatures closer to freezing at night. Solar warming will likely be a problem when the sun shows itself again Thursday or Friday.

Problem Specific Travel Advisory – Be cautious just after a heavy rain-snow event. Let things settle. As days begin to warm again, plan your activity with the daily warming in mind.

List of Avalanche Problems <here>

GENERAL TRAVEL ADVISORY: 

  • Travel on glaciers requires the gear and skills for crevasse rescue.
  • Snow bridges are weakening.

AVALANCHE ACTIVITY:  Many new size 2 to 2+ avalanches have occurred since April 29th with a scattering of size 3. Most of them seem natural, while one size 3 was human triggered Sunday on the lower face below Python at about 3,000′. Most all seem to be starting as point releases, then branch out by pulling wet slabs, sliding on the Damalanche facet interface, before trenching down to ground in thinner spots. These all seem to have happened during the sunny, warm spell.

20140504_171524[1]

  • Avalanche sizing via destructive scale <here>
  • Avalanche size estimation aid <here>.

SNOWPACK DISCUSSION:  With the last warm and sunny period, we have seen that the facets above the Damalanche crust can promote a problem. Many slides have used the heavy, wet snow above this weak layer to pull in more snow via wet slabs to create larger events. Other shallower areas have directly trenched down to the depth hoar at the ground-vegetation.  Keep an eye out for natural activity with added rain and weight to the snowpack. This will only add more lubricant to the weak layers that a slab could slide on. Additionally, consider the increasing temperatures and solar effect as the days warm and skies clear later in the week.

Any new snow that falls at the higher elevations should be inspected to see how it is bonding with the old surfaces below. Most old surfaces are hard and won’t play well with new snow util it is given time. On the other hand, north aspects could have preserved dry snow underneath, but look out for near-surface facets that could be buried.

Snow below treeline is melting fast and isothermal. Many aspects at the mid elevations that get a lot of solar radiation are not far behind.

Please CONTRIBUTE to the Snow Observations page <here>.

Photos and observations are welcome and helpful for all to stay in tune with the current conditions. Thanks!

WEATHER:  While overcast skies and precipitation have settled in, the rain should start to let up Wednesday and clouds start to break Thursday. Hope for a good amount of sun on Friday and Saturday. Overnight temperatures have dipped down to freezing at the elevation of Thompson Pass. That means new snow fell at higher elevations.

WINDS & TEMPERATURES (Past 24 Hours) : VALDEZ THOMPSON PASS
Average Wind Speed / Direction 6 mph / W 12 mph / SSE
Max Wind Gust 13 mph 25 mph
Temperature Min / Max (deg F) 37 / 45 31 / 34
SNOW & PRECIPITATION:
VALDEZ
THOMPSON PASS
24 Hour Snow / Water Equiv.
?” / ?”
trace” / 0.3″
May Snow / Water Equiv.
?” / ?”
trace” / 0.3″
Current Snow Depth
?”
30″
Total Winter Snowfall
?”
335″
(Valdez NWS office has permanently closed=no new data)

 

MAY 1st SNOW SURVEY:
Location: Depth: Inches of Water: Percent Water:
Valdez 15 5 32%
Milepost 18 20 8 38%
Worthington Glacier 53 20 37%
Milepost 37 31 10 33%

Weather Quicklinks:

  • Valdez Glacier UAF weather station at 6600 feet <data here> <map here>.
  • Thompson Pass weather <here>.
  • Further weather resources <here>
  • Summary of January 13-30 avalanche cycle<here>
  • Season Summary from the beginning of winter to January 8 <here>

SNOW CLIMATE ZONES:

  • Maritime (Coastal) – from the Port of Valdez to Thompson Pass, all waters flowing into Valdez Arm and everything south of Marshall Pass.
  • Inter-mountain (Transitional) – between Thompson Pass and Rendezvous Lodge.
  • Continental (Interior) – the dry north side of the Chugach (north of 46 Mile, including the Tonsina River).

2014 marks the ninth year of public avalanche safety bulletins for the Valdez Chugach mountains October through May

Free smart phone avalanche forecasts at: http://www.avalancheforecasts.com/

Tuesday-Friday, May 6-May 9, 2014

Tuesday-Friday, May 6-May 9, 2014     Issued/Updated: 7:00 AM 5/6/14

AVALANCHE DANGER RATING:

TUESDAY:     WEDNESDAY:     THURSDAY & FRIDAY:
Morning: Afternoon:   Morning: Afternoon:   Morning: Afternoon:
Above 3,000′ Above 3,000′ Above 3,000′ Above 3,000′ Above 3,000′ Above 3,000′
Moderate-150x150 high icon Moderate-150x150 high icon Moderate-150x150 high icon
Below 3,000′ Below 3,000′ Below 3,000′ Below 3,000′ Below 3,000′ Below 3,000′
Moderate-150x150 Considerable Moderate-150x150 Considerable Moderate-150x150 Considerable

DANGER SCALE details <here>. Memorize this so you know what the colors and numbers are based on.

Elevations:
  • Alpine – Above 2,000 feet
  • Treeline – 2,000 feet
  • Below treeline – Below 2,000 feet

 

FORECASTER CONFIDENCE: FAIR

DANGER TREND:  The danger will increase when a reasonable amount of new precipitation falls or the the temperature rises again after this weather passes. New rain and/or snow will only add weight and stress to an already weakened snowpack after the long stint of warm days with no freezing at night. Snow at the higher elevations will be resting on very firm layers that will take awhile to begin the bonding process. Once the sun shows itself again and/or temperatures rise significantly, be concerned about a series of new avalanches to occur. With the temperatures and precipitation decreasing Wednesday night, the danger should decrease until a warming afternoon could cause some activity.

AVALANCHE PROBLEM(S):  A variety of new and old avalanche problems can reveal themselves during the spring thaw. Wet snow avalanches, deep persistent slab releases and cornice/icefall failure can occur independently or as part of a chain reaction. icon-wet avalanches

Loose Wet & Wet Slab Avalanches: The snow has had a series of warm days to progressively weaken it with limited freezing at night. New rain and/or snow will only add stress to this despite cooler temperatures closer to freezing at night. Solar warming will be a problem when the sun shows itself again.

Problem Specific Travel Advisory – Be causes just after a heavy rain-snow event. Let things settle. As days begin to warm again, plan your activity with the daily warming in mind.

List of Avalanche Problems <here>

GENERAL TRAVEL ADVISORY: 

  • Travel on glaciers requires the gear and skills for crevasse rescue.
  • Snow bridges are weakening.

AVALANCHE ACTIVITY:  Many new size 2 to 2+ avalanches have occurred in the last few days with a scattering of size 3. Most of them seem natural, while one size three was human triggered Sunday on the lower face below Python at about 3,000′. Most all seem to be starting as point releases, then branch out by pulling wet slabs, sliding on the Damalanche facets, before trenching down to ground in thinner spots. These all seem to have happened during the sunny, warm spell.

  • Avalanche sizing via destructive scale <here>
  • Avalanche size estimation aid <here>.

WEATHER:  Overcast skies have settled in, while precipitation should follow, most intensely Tuesday afternoon and into Wednesday or Thursday. Overnight temperatures will dip down closer to freezing the next few nights on the pass. That could mean new snow at higher elevations. The weather will start to break Thursday with a higher chance of sun on Friday.

  • Valdez Glacier UAF weather station <data here> at 6600 feet <map here>.
  • Thompson Pass weather <here>.
  • Further weather resources <here>

SNOWPACK DISCUSSION:  With the last warm and sunny period, we have seen that the facets above the Damalanche crust can be a problem. Many slides have used this weak layer to pull in more snow via wet slabs to create larger events. Other shallower areas have directly trenched down to the depth hoar at the ground.  Keep an eye out for natural activity with added rain and weight to the snowpack. This will only add more lubricant to the weak layers that a slab could slide on. Additionally, consider the increasing temperatures and solar effect as the days warm and skies clear later in the week.

Any new snow that falls at the higher elevations should be inspected to see how it is bonding with the old surfaces below. Most old surfaces are hard and won’t play well with new snow util it is given time. On the other hand, north aspects could have preserved dry snow underneath, but look out for near-surface facets that could be buried.

Snow below treeline is melting fast and isothermal. Many aspects at the mid elevations that get a lot of solar radiation are not far behind.

Please CONTRIBUTE to the Snow Observations page <here>. Photos and observations are welcome and helpful for all to stay in tune with the current conditions. Thanks!

SNOW & PRECIPITATION (updated April 30):

 SEASONAL TOTALS:
VALDEZ
THOMPSON PASS
24 Hour Snow
0″
0″
April Snow
?”
9″
Winter Total
?”
335″
Base
?”
48″
24 Hr Water Equivalent
?”
0″
April Water Equivalent
?”
0.7″
(Valdez NWS office has permanently closed=no new data)

 

May 1st Snow Survey:
Location: Depth: Inches of Water: Percent Water:
Valdez 15 5 32%
Milepost 18 20 8 38%
Worthington Glacier 53 20 37%
Milepost 37 31 10 33%

Summary of January 13-30 avalanche cycle <here>

Season Summary from the beginning of winter to January 8 <here>

SNOW CLIMATE ZONES:

  • Maritime (Coastal) – from the Port of Valdez to Thompson Pass, all waters flowing into Valdez Arm and everything south of Marshall Pass.
  • Inter-mountain (Transitional) – between Thompson Pass and Rendezvous Lodge.
  • Continental (Interior) – the dry north side of the Chugach (north of 46 Mile, including the Tonsina River).

2014 marks the ninth year of public avalanche safety bulletins for the Valdez Chugach mountains October through May

Free smart phone avalanche forecasts at: http://www.avalancheforecasts.com/