Avalanche forecast for Nordenskiöld Land Sunday 2019-02-03

2
Moderate
Published:

There is a persistent weak layer of facets buried in the snow cover that may be triggered by a skier or snowmobile. Remote triggering possible on hotspots or on convex terrain where the snow cover is thin. Fresh wind slabs may also form avalanches.

Persistent weak layer (slab avalanches)

Buried weak layer of faceted snow near surface

Keep distance to each other when traveling in avelanche terrain. NB, remote triggering is possible. Make very conservative route choices, especially in unknown terrain, after snowfall and if temperatures rise. Identifying areas where the weak layer is present might be difficult and requires experience. Danger signs are whoumpf-sounds and cracking which means that you influence weak layers and should avoid avalanche terrain. However, absence of signs does not mean it is safe.
3 - Large
High additional load
Specific steep slopes
Possible

Wind drifted snow (slab avalanches)

Buried weak layer of new snow

Be careful and keep distance to each other in steep (above 30 degrees) terrain with fresh wind deposited snow, especially convex terrain. An avalanche is easier to trigger where wind slabs are thin or soft. Look for areas where the wind recently has deposited snow, typically behind ridges, ribs and in gullies. Remember that local wind effects will cause variation in where the wind slabs occur.
2 - Medium
Low additional load
Specific steep slopes
Possible

What are avalanche problems?

Observations the last 3 days (map placed)

1 mm precipitation.
Fresh breeze from southeast., change to moderate gale from the southeast during the afternoon.
-11 °C to -8 °C at 700 m a.s.l.
Cloudy.

For updated info, please visit yr.no
0 mm precipitation.
Strong breeze from south.
-9 °C to -8 °C at 700 m a.s.l.
Cloudy.

For updated info, please visit yr.no

Observations the last 3 days

Nordenskiöld Land / SVALBARD

Snow

03.02.2019 kl. 08:16

76 masl

Martini@unis (****)

Image Of Weather
Image 1 of 3 Of:  Weather Copyright:  Martini@unis Comment:  Lett bakkefokk igjennom natta
Image Of Snow Cover
Image 2 of 3 Of:  Snow Cover Copyright:  Comment:  Adventdalen fra Todalen
Image Of Snow Cover
Image 3 of 3 Of:  Snow Cover Copyright:  Comment:  Bolternosa ytterst i Todalen

Snow Cover

Some snow drift Storm slab (soft slab) Dry Lite snø tilgjengelig for transport, men lett snøfokk igjennom hele siste døgn nede i Todalen flytter rundt på det lille som er av løssnø. Vind far S, fokksnø legger seg nå opp i N vendt terreng

Weather

No precipitation -3 °C 10 m/s from S ↑ Lette snøbyger igjennom lørdag. Vind fra S, opptil frisk bris i perioder, økende på kvelden og natt til søndag. Søndag morgen vind fra S rundt 10 m/s, lett bakkefokk ytterst i Todalen

ObsID: 178949

Nordenskiöld Land / SVALBARD

Snow

02.02.2019 kl. 14:30

491 masl

mrtnlvs (Unknown)

Image Of Notes
Image 1 of 1 Of:  Notes Copyright:  mrtnlvs Comment:  Utydelig i avdeling i fersk vindparken snø.

Snow Cover

300 cm in total Moderate snow drift 10 cm new snow Some loose snow (1-10cm) Dry Lett bundet øverste 15cm, hardt og stabilt snødekke videre nedover

Tests

ECTN Good

Danger Sign

No signs observed

Avalanche Problems

Notes

Weather

1 m/s from SE ↖ Vind på sørsiden av Larshjerta, transport av snø. Øverste 15 hm tydelig vindpåvirket

ObsID: 178910

Nordenskiöld Land / SVALBARD

Snow

02.02.2019 kl. 12:45

208 masl

HoltH@unis (***)

Image Of Avalanche Activity
Image 1 of 1 Of:  Avalanche Activity Copyright:  HoltH@unis

Avalanche Activity

2. Feb. During the day (+01:00) Dry slab avalanche One (1). 1 - Small One small cornice fall / slab avalanche that appears to have released in the last two days (debris still looked fresh). Small avalanche just on the river bank, but possibly indicative of the potential for other cornice or slab failures in more consequential terrain.

ObsID: 178876

Nordenskiöld Land / SVALBARD

Snow

02.02.2019 kl. 11:57

140 masl

S.Brochmann@ANG (Unknown)

Image Of Weather
Image 1 of 1 Of:  Weather Copyright:  Brochmann Comment:  Lett snødrev, 300 meter sikt. Vind og snø bygget seg mer og mer opp ila dagen.

Weather

Snow 5 °C 12 m/s from SE ↖ 100% clouds

ObsID: 178847

Nordenskiöld Land / Sukkertoppen

Snow

01.02.2019 kl. 13:43

130 masl

HoltH@unis (***)

Image Of Snow Cover
Image 1 of 1 Of:  Snow Cover Copyright: 

Snow Cover

Sukkertoppen snow cover / snow depths from terrestrial laser scanning on 2019-01-30. Snow cover represented in this figure corresponds well with the photos of Sukkertoppen from: https://www.regobs.no/Registration/178253. Relatively little snow across most of Sukkertoppen's western aspect, except for the upper start zone and around the snow fences. The black dot indicates the location of the DRIVA snow depth measurement station. No snow accumulations in excess of 2 meters except for right around the snow fences.

ObsID: 178709

Nordenskiöld Land / Svalsatveien

Snow

01.02.2019 kl. 10:30

377 masl

MariE (Unknown)

Image Of Snow Profile
Image 1 of 1 Of:  Snow Profile Copyright: 

Avalanche Danger Assessment

2 Moderate observasjonen gjelder for Svalsatveien/Skjæringa og er ikke representativt for regionen. Generelt avblåst, finner noe myk fokksnø i isolerte leområder, som fortsatt viste tegn til å sprekke opp når vi gikk over. Observert kantkornlag over og under skare, men skal mye til å komme gjennom harde is og skarelag for å nå ned til disse. værvarselet gir ingen indikatorer på en økende skredfare nå. Forecast correct

Snow Cover

220 cm in total No snowdrift 0 cm new snow Crust Dry Snødekket er generelt hardt, dominert av hard fokksnø, men vi finner også islag/skarelag med kantkorn både over og under denne skaren. I helt isolerte lommer finnes myk fokksnø, med dårligere binding til gammel fokksnø/skare, men observerte dette kun der fresen har lagt igjen hauger som gir le for vinden (så finnes nok i leområder andre steder). Vi fikk brudd i det tynne kantkornlaget over skare på ECTP16@75.

Tests

ECTP16@42cmQ2 Medium

Danger Sign

No signs observed

Avalanche Problems

Dry slab avalanche Buried weak layer of faceted snow above a crust Within a meter The collapsing weak layer is thin < 3 cm. Difficult to trigger N, NW tydelige kantkorn, i tynt lag over skare. Skal høy belastning til for å løse ut. Her tykt overliggende lag med hard fokksnø og islag. Kan være et problem der snødekket er tynt.

Weather

No precipitation -4.6 °C 9 m/s from S ↑ 70% clouds

Snow Profile

9 cm P RG 1 mm/0 mm, 8 cm P RG 0 mm/0 mm, 7 cm 1F RG/RGxf 1 mm/0 mm, 17 cm P MF/RG 1 mm/2 mm, 1 cm 4F FC 1 mm/0 mm Skarelag, 1 cm I MFcr 0 mm/0 mm, 5 cm 4F FC 0 mm/0 mm, 49 cm P RG 0 mm/0 mm, 20 cm P RG 0 mm/0 mm -9.7 °C @ 0 cm, -10 °C @ 10 cm, -10 °C @ 30 cm, -10 °C @ 50 cm, -10 °C @ 70 cm, -9.3 °C @ 80 cm, -9 °C @ 90 cm, -7.9 °C @ 100 cm, -7.3 °C @ 110 cm, -7 °C @ 117 cm, -6.4 °C @ 118 cm 1 test connected to snow profile

ObsID: 178687

Nordenskiöld Land / Larsbre Øst

Snow

31.01.2019 kl. 20:00

547 masl

Kjetil@obskorps (****)

Image Of Snow Profile
Image 1 of 3 Of:  Snow Profile Copyright: 
Image Of Tests
Image 2 of 3 Of:  Tests Copyright:  Comment:  Snøprofilen i virkeligheten
Image Of Tests
Image 3 of 3 Of:  Tests Copyright:  Comment:  Q1

Avalanche Danger Assessment

2 Moderate Observasjon tatt for område Longyearbyen. Et stabiliserende fokksnøproblem over et vedvarende kantkornproblem. Alle høyder i Vest-lig sektor. Mulig step-down. Med vinddreining til sør, og etter svalbardforhold endel snø tilgjengelig så vil fokksnøproblemet også komme i norlig sektor. Forecast correct

Snow Cover

Det har ila de siste par dagene lagt seg endel fokksnø i vestvendte heng. Fra omlag 5 til 30 med 4f til 1f. Under dette er det som registrering 178146

Tests

ECTP6@17cmQ1 Poor

Danger Sign

No signs observed

Avalanche Problems

Dry slab avalanche Poor bonding between layers in wind deposited snow Within half a meter The overlying slab is soft. Easy to trigger 2 - Medium N, NE, SW, W, NW Fokksnøproblemet er der enda, men har stabilsert seg noe fra onsdagen.

Dry slab avalanche Buried weak layer of faceted snow above a crust The weak layer collapses easily and clean (easy propagation). The collapsing weak layer is thin < 3 cm. Easy to trigger 3 - Large N, NE, SW, W, NW Dette kantkornproblemet finnes over alt, men varierende grad av hvor begravet det er. Det er enten få områder og lett å løse ut, eller noen og vanskelig å løse ut.

Weather

-5 °C 5 m/s from E ←

Snow Profile

5 cm 4F DF 0 mm/0 mm, 7 cm 1F DF 0 mm/0 mm, 5 cm P RG 0 mm/0 mm, 1 cm 4F FC 1 mm/0 mm, 1 cm K/1F MFcr 0 mm/0 mm, 1 cm 4F FC 1 mm/0 mm, 1 cm P MFcr 0 mm/0 mm, 13 cm 1F RGxf 1 mm/0 mm, 33 cm P RGxf 1 mm/0 mm, 3 cm K IF 0 mm/0 mm, 2 cm 1F FC 2 mm/0 mm, 25 cm P MF 0 mm/0 mm, 5 cm 1F FC 2 mm/0 mm 1 test connected to snow profile Temperaturen i profilen er ikke riktig.

ObsID: 178619

Nordenskiöld Land / SVALBARD

Snow

31.01.2019 kl. 12:35

545 masl

HoltH@unis (***)

Image Of Snow Cover
Image 1 of 5 Of:  Snow Cover Copyright:  HoltH@unis Comment:  soft snow surface.
Image Of Snow Profile
Image 2 of 5 Of:  Snow Profile Copyright: 
Image Of Snow Profile
Image 3 of 5 Of:  Snow Profile Copyright: 
Image Of Snow Cover
Image 4 of 5 Of:  Snow Cover Copyright:  Comment:  mot helvetiafjellet / adventdalen
Image Of Snow Cover
Image 5 of 5 Of:  Snow Cover Copyright:  Comment:  adventalen mot gruve 7

Avalanche Danger Assessment

2 Moderate Based on my observation trip today, I came up with the following inputs to ADAM: Fokksnø problemet: mulig utløsningssannsynlighet to str. 2. Vedvarende svakt lag problemet: lite sannsynlig to str. 3. This gives a moderat (2) rating. With continued mild weather, the wind slab problem should continue to stabilize in the absence of strong winds or more precipitation. Mild weather won't make the faceted layers worse, but looks like we are probably stuck with a persistent weak layer problem for the foreseeable future. Forecast too high The forecast for today describes the avalanche problems well. It's possible that more snow has fallen and wind slab problems are worse further south in the region, but based on my observations in this location today, a moderate rating seems more appropriate.

Snow Cover

125 cm in total Some snow drift 0 cm new snow Snow line at 0 masl Storm slab (soft slab) Dry Variable snow cover as normal for Spitsbergen. The easterly winds over the past few days have had their way with the snow cover, moving most of the fresh snow into wind deposits on westerly aspects. On Arctowskifjellet, 1F wind slabs 10-50 cm deep lie in most leeward locations. Ridges and easterly aspects I observed were blown back down to the most recent melt freeze crust. Wind has densified the most recent snow to the point that most of the snow from this week is now no longer readily available for wind transport.

Danger Sign

Whumpf sound Område: I denne fjellsiden. Beskrivelse: Bare et drønn på veien opp rundt 250 moh

Avalanche Problems

Dry slab avalanche Buried weak layer of faceted snow beneath a crust Within a meter The collapsing weak layer is thin < 3 cm. A big and identifiable crystal in the weak layer. Very difficult to trigger 3 - Large SW, W, NW So far I have only observed this avalanche problem on westerly aspects, so am a little unsure of its distribution regionally. Observed well-developed facets both over and under the most recent melt-freeze crust in the snowpack. In stability tests, the slightly larger facets under the crust were more reactive. In a modified ECT in which I removed the top 30 cm of wind slab and tested the facet layers specifically, i was able to get the facet layer under the crust to propagate after 19 (ECTP 19). However this layer is well-bridged by the hard melt-forms over it and I think it would be fairly difficult to trigger an avalanche on this layer. Nevertheless, in the event that this layer was affected by a skier, snowmobiler, or a smaller wind slab avalanche, this layer has the potential to produce sizable avalanches. Low probability / high consequence scenario.

Dry slab avalanche Poor bonding between layers in wind deposited snow Within half a meter The collapsing weak layer is thin < 3 cm. Difficult to trigger 2 - Medium SW, W, NW Wind slabs from earlier in the week appear to be stabilizing nicely, based on my observations. Stability tests show that it is possible to initiate a fracture in the fresh wind slabs, but these fractures are not propagating. Stomping on fresh drifts did not yield any signs of instability. In general, the wind slabs in this location felt fairly dense, homogenous, and decently well bonded.

Weather

Snow -5 °C 5 m/s from E ← 50% clouds Broken clouds most of the morning / early afternoon. Light snow on Arctowskifjellet between 1130 and 1330. Light easterly winds, fairly warm air.

Avalanche Activity

31. Jan. During the day (+01:00) No avalanche activity

ObsID: 178571

The bulletin does not include a detailed text about the avalanche conditions. This is only given in Norwegian. Translate it using google translate if you like. The text result will be informative, and most likely amusing

For planning your trip and recognizing avalanche terrain, use maps.

Norway has 1:50 000 maps for the whole country. Maps can be bought at bookstores and sports shops, or printed from the net.

Visit www.ut.no for topographic maps online. For slope angle maps, see NGI slope angel maps ("helning" means slope angle).

Modelled snowpack and historic and current weather information can be found on the webpage senorge.no. This site uses information from the weather stations and interpolate values from the stations for gridded maps.

Detailed weather forecast can be found online at www.yr.no or www.storm.no. Yr.no is also in English, but the weather in text format is only given in Norwegian.