Avalanche forecast for Heiane Wednesday 2019-12-11

3
Considerable
Published:

Demanding conditions, avoid areas with fresh wind deposited snow. In lower terrain is it conditions for wet avalanches

Illustrasjon av ferdselsråd Wet surface: Avoid terrain steeper than 30 degrees. Avoid also runout zones.
Illustrasjon av ferdselsråd Avoid terrain traps.

Wind drifted snow (slab avalanches)

Buried weak layer of new snow

Read more about the avalanche problem
2 - Medium
Low additional load
Widespread steep slopes
Possible

Wet snow (slab avalanches)

Water pooling in/above snow layers

Read more about the avalanche problem
2 - Medium
Spontaneous release
Specific steep slopes
Possible

What are avalanche problems?

Observations the last 3 days (map placed)

20 mm precipitation, up to 40 mm in the most exposed areas.
Breeze from northwest., change to moderate gale from the southeast during the afternoon.
-10 °C to 2 °C at 1100 m a.s.l.
Plus degrees up to 1000 m a.s.l. during the evening.
Cloudy.

For updated info, please visit yr.no
25 mm precipitation, up to 35 mm in the most exposed areas.
Strong breeze from southwest.
-3 °C to 1 °C at 1100 m a.s.l.
Plus degrees up to 1200 m a.s.l. wednesday night.
Cloudy.

For updated info, please visit yr.no

Observations the last 3 days

Heiane / Sirdal

Snow

10.12.2019 kl. 11:48

987 masl

Salvesen@obskorps (***)

Image Of Danger Sign
Image 1 of 14 Of:  Danger Sign Copyright:  Salvesen@obskorps
Image Of Danger Sign
Image 2 of 14 Of:  Danger Sign Copyright:  Salvesen@obskorps Comment:  Det har blåst hardt under siste snøfall
Image Of Danger Sign
Image 3 of 14 Of:  Danger Sign Copyright:  Salvesen@obskorps
Image Of Avalanche Activity
Image 4 of 14 Of:  Avalanche Activity Copyright:  Salvesen@obskorps Comment:  Trolig mer enn 24 timer gammelt. Skavlknekk
Image Of Weather
Image 5 of 14 Of:  Weather Copyright:  Salvesen@obskorps
Image Of Snow Cover
Image 6 of 14 Of:  Snow Cover Copyright:  Salvesen@obskorps Comment:  550moh
Image Of Snow Cover
Image 7 of 14 Of:  Snow Cover Copyright:  Salvesen@obskorps Comment:  700moh
Image Of Snow Cover
Image 8 of 14 Of:  Snow Cover Copyright:  Salvesen@obskorps Comment:  800moh
Image Of Snow Cover
Image 9 of 14 Of:  Snow Cover Copyright:  Salvesen@obskorps Comment:  1000moh
Image Of Tests
Image 10 of 14 Of:  Tests Copyright:  Salvesen@obskorps
Image Of Snow Profile
Image 11 of 14 Of:  Snow Profile Copyright:  Salvesen@obskorps
Image Of Snow Profile
Image 12 of 14 Of:  Snow Profile Copyright:  Salvesen@obskorps Comment:  Tydelig todeling av snødekket.
Image Of Avalanche Problems
Image 13 of 14 Of:  Avalanche Problems Copyright:  Salvesen@obskorps Comment:  Sprekker opp rundt ski
Image Of Snow Profile
Image 14 of 14 Of:  Snow Profile Copyright: 

Tests

LBT@23cmQ2 Svakere lag i fokksnøen løsner ved middels manipulering.

Danger Sign

Recent snowdrift Område: Fylket/varslingsregion

Avalanche Activity

10. Dec. During the day (+01:00) No avalanche activity

Weather

Snow -5 °C 6 m/s from S ↑ 100% clouds Dalende temperaturer og stort sett oppholdsvær siste døgn. Det kommer vær nå. Lett snødrev i luften.

Snow Cover

40 cm in total Some snow drift Snow line at 600 masl Some loose snow (1-10cm) Dry Snødekket fremstår nå som sammenhengende og kompakt/bærende på ski fra ca 700m. Snøoverflaten utvikler seg fra litt tørr løssnø (begynnende kant) i lavereliggende områder før kompakt fokksnø på skare overtar høyere oppe. Mye sastrugi tyder på kraftig snøtransport under uværet tidligere i uken.

Avalanche Danger Assessment

2 Moderate Snødekket fremstår som relativt stabilt på tur i dag, noe som må ses i sammenheng med et mildt snødekke og et døgn med fallende temperaturer som raskt har bundet snøen. Skredfaren per nå begrenser seg til noe ustabilitet innad i fokksnøen eller enkelte steder fokksnø mot skare. Det er meldt ruskevær og mye nedbør neste døgnet noe som vil forverre situasjonen. Forecast correct Trolig FG 2 på nåværende tidspunkt, men med været som er meldt er det naturlig å forvente en FG3 situasjon ila ettermiddag og kveld.

Avalanche Problems

Dry slab avalanche Poor bonding between layers in wind deposited snow Within half a meter The collapsing weak layer is thin < 3 cm. The overlying slab is soft. Easy to trigger 2 - Medium N, NE, SW, W, NW above 700 masl

Snow Profile

23 cm 1F+ RG 0 mm D-M, 27 cm P RG 1 mm M, 2 cm K MFcr M, 10 cm 1F MF 1 mm M, 7 cm K MFcr M, 3 cm 1F+ MF 1 mm M, 2 cm K MFcr M, 3 cm 1F MF M, 1 cm K MFcr M, 22 cm 1F/4F MF/MFsl W -5 °C @ 0 cm, -6.7 °C @ 10 cm, -4.8 °C @ 20 cm, -2.6 °C @ 30 cm, -1.4 °C @ 40 cm, -0.3 °C @ 50 cm, -0.1 °C @ 60 cm, -0.1 °C @ 70 cm, -0.1 °C @ 80 cm, -0.1 °C @ 90 cm, -0.1 °C @ 100 cm 1 test connected to snow profile

ObsID: 201495

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.

For slope angle maps, download the app Varsom Regobs on App Store | Google Play or see our slope angle map at senorge.no ("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.