Avalanche warning for region Hallingdal Monday 15.02.2021

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The weak layer collapses easily and clean (easy propagation). A big and identifiable crystal in the weak layer. • Very difficult to trigger • 1 - Small • Some steep slopes N, W, NW above 1200 masl • Funnet i høyder fra 1100-1400

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The weak layer collapses easily and clean (easy propagation). The collapsing weak layer is thin < 3 cm. The overlying slab is soft. A big and identifiable crystal in the weak layer. • Very easy to trigger • 1 - Small • Some steep slopes N, SW, W, NW above 1500 masl • Observert ned til ca 1200m

Avalanche Problems

• Dry slab avalanche • Buried weak layer of faceted snow near surface • The weak layer collapses easily and clean (easy propagation). The collapsing weak layer is thin < 3 cm. A big and identifiable crystal in the weak layer. • Easy to trigger • 1 - Small • Few steep slopes NE, E, SE between 1300 masl and 1100 masl

Avalanche Problems

• Dry slab avalanche • Buried weak layer of faceted snow near surface • Within half a meter • The collapsing weak layer is thin < 3 cm. A big and identifiable crystal in the weak layer. • Difficult to trigger • 2 - Medium • Some steep slopes N, NE, E, SE, S, SW, W, NW above 1200 masl

Avalanche Problems

• Dry slab avalanche • Buried weak layer of faceted snow near surface • Within a meter • A big and identifiable crystal in the weak layer.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • Easy to trigger • 1 - Small • Some steep slopes N, W, NW above 1100 masl • Påvist problem mellom 1200 til 1400 meter i området Systerskarsfjellet.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The weak layer collapses easily and clean (easy propagation). The collapsing weak layer is thin < 3 cm. The overlying slab is soft. A big and identifiable crystal in the weak layer. • Easy to trigger • 1 - Small • Some steep slopes N, NE, E, SE, S, SW, W, NW above 1100 masl

Avalanche Problems

• Buried weak layer of faceted snow near surface • Within half a meter • Difficult to trigger • 1 - Small • S between 1200 masl and 1100 masl

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The collapsing weak layer is thin < 3 cm. The overlying slab is soft. A big and identifiable crystal in the weak layer. • Very easy to trigger • 1 - Small • Few steep slopes SE between 1200 masl and 1100 masl

Avalanche Problems

• Dry slab avalanche • Buried weak layer of faceted snow near surface • Within half a meter • The weak layer collapses easily and clean (easy propagation). A big and identifiable crystal in the weak layer. • Very easy to trigger • 2 - Medium • Some steep slopes N, NE, E, SE, S, SW, W, NW between 1500 masl and 1000 masl • Me fann eit vedvarande svakt lag av kantkorn høgt i snødekket. Fokksnøen som låg på toppen var av veldig varrierande hardheit og tjukkelse. Dette kunne me sjå ut i frå andre pitar som blei gravd i området. Nokre stadar ligg FClaget so lågt i snødekket at ein skilaupar ikkje kan påverke det medan andre stader ligg det høgt oppe i snødekket og utgjer eit reelt skredproblem.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of faceted snow near surface • Within half a meter • A big and identifiable crystal in the weak layer. • 2 - Medium • Some steep slopes N, NE, E, SE, S, SW, W, NW between 1500 masl and 900 masl • Vi fikk ikke påvirket det svake laget her, men det er utbredt i området og kan muligens påvirkes enkelte steder.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The weak layer collapses easily and clean (easy propagation). The collapsing weak layer is thin < 3 cm. A big and identifiable crystal in the weak layer. • Very easy to trigger • 1 - Small • Some steep slopes N, NE, E, SE, S, SW, W, NW above 1000 masl • Fra 1000-1400 moh er rimkrystallene ca 1-2 cm store. Fra 1400-1600 er rimkrystallene ca 2-3 cm store. Dette gjelder i alle himmelretninger med unntak av sterkt vindutsatte steder. Variere med å ligge i snøoverflaten til ca 5 cm under fokksnøen.

• Dry slab avalanche • Buried weak layer of faceted snow near surface • Within half a meter • A big and identifiable crystal in the weak layer. • Difficult to trigger • 2 - Medium • Some steep slopes NW between 1400 masl and 1000 masl • 5 cm Kantkorn lag i varierende dybde på 20-40 cm, stor variasjon i dybde innenfor små områder.

Avalanche Problems

• Loose dry avalanche • The weak layer collapses easily and clean (easy propagation). • Very easy to trigger • E, SE

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The weak layer collapses easily and clean (easy propagation). The collapsing weak layer is thin < 3 cm. • Easy to trigger • 1 - Small • Some steep slopes SE, S • Størrelse satt til 1 - Små grunnet nåværende snøfokkmengde, 1-10cm. Merk at resultat og snømengder kun gjelder lokalt på teststedet. Områder med dypere snøfokk og evt fremtidig snøtransport vill øke faren.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The weak layer collapses easily and clean (easy propagation). The collapsing weak layer is thin < 3 cm. The overlying slab is soft. A big and identifiable crystal in the weak layer. • Very easy to trigger • 1 - Small • Many steep slopes N, NE, E, SE, S, SW, W, NW above 1100 masl • Store rimkrystaller (6-9 mm) som stedvis er sammenfrosset og lett nedføyket (armert) av et slør av nysnø - stedvis nedføyket under fersk fokksnø. Kun utsatte steder vinden har klart å blåse rent for rim. Ved tilførsel av snø og vind vil dette bli spennende i høyden.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of faceted snow near surface • Within half a meter • The weak layer collapses easily and clean (easy propagation). A big and identifiable crystal in the weak layer. • Easy to trigger • 2 - Medium • Some steep slopes SW, W above 1100 masl • - observerte harde RG lag over og under det svake kantkornlagt (3-5mm), dette i vindpåvirket områder. - Vi hadde én observasjon i Sørvest som ga drønn og sprekker som skjøt 4-5m. - Vi utelukker ikke dette problemet i utsatte områder i andre himmelretninger.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The weak layer collapses easily and clean (easy propagation). The collapsing weak layer is thin < 3 cm. A big and identifiable crystal in the weak layer. • Easy to trigger • Some steep slopes E, SE above 1100 masl

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within a meter • The weak layer collapses easily and clean (easy propagation). The collapsing weak layer is thin < 3 cm. A big and identifiable crystal in the weak layer. • Very easy to trigger • 2 - Medium • Some steep slopes N, NE, NW between 1400 masl and 1000 masl

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The weak layer collapses easily and clean (easy propagation). A big and identifiable crystal in the weak layer. • Easy to trigger • 2 - Medium • Some steep slopes N, W, NW between 1500 masl and 1200 masl

Avalanche Problems

• Dry slab avalanche • Buried weak layer of faceted snow above a crust • Within half a meter • A big and identifiable crystal in the weak layer. • Difficult to trigger • 1 - Small • Some steep slopes N, NE above 1100 masl • Skredproblem er kun gjeldende lokalt N og NØ fra tregrense til en runder toppen (1609 i kartet) i 1500moh og går mot annen himmelretning. Her endres snødekket i stor grad, rim og hardere underliggende snø.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of faceted snow near surface • Within half a meter • The collapsing weak layer is thin < 3 cm. A big and identifiable crystal in the weak layer. • Easy to trigger • 2 - Medium • Few steep slopes N, NE, E, SE, S, SW, W, NW above 1000 masl

Avalanche Problems

• Dry slab avalanche • Poor bonding between layers in wind deposited snow • Within half a meter • The weak layer collapses easily and clean (easy propagation). The collapsing weak layer is thin < 3 cm. • Very easy to trigger • 1 - Small • Few steep slopes SE, S, SW between 1300 masl and 1000 masl

• Dry slab avalanche • Buried weak layer of faceted snow near surface • Within a meter • A big and identifiable crystal in the weak layer. • Difficult to trigger • 2 - Medium • Few steep slopes SE, S, SW between 1300 masl and 1000 masl

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. • Very easy to trigger • 1 - Small • Few steep slopes SE, S, SW between 1200 masl and 1000 masl • Tester ga utslag i øverste snødekket grunnet svakelag under flak.

Avalanche Problems

• Loose snow • Very difficult to trigger • 1 - Small • Few steep slopes N, W, NW between 1400 masl and 1000 masl • Akkurat i den piten eg grov fanst det ikkje noko svakt lag. Men ved 3 andre pitar i området var det eit svakt lag av kankorn under eit flak av fokksnø. Ein kan dermed annta at dette FC laget er utbreidd i fjellområdet, medan akkurat i piten min var snøen prega av hard fokksnø.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • A big and identifiable crystal in the weak layer. • Easy to trigger • 1 - Small • Few steep slopes N, NE, NW above 1300 masl • SH laget var veldig lokalt på få steder under et tynt RG lag. Store deler av heng var nesten bare RG ned til 1 m.

Avalanche Problems

• Dry slab avalanche • The weak layer collapses easily and clean (easy propagation). • Easy to trigger • 1 - Small • Some steep slopes SE between 1500 masl and 1000 masl

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The collapsing weak layer is thin < 3 cm. • Easy to trigger • 2 - Medium • Some steep slopes E, SE above 1100 masl

Avalanche Problems

• Dry slab avalanche • Buried weak layer of faceted snow above a crust • Within half a meter • A big and identifiable crystal in the weak layer. • Difficult to trigger • 1 - Small • Some steep slopes N, NE above 1100 masl • Skredproblem er kun gjeldende lokalt N og NØ fra tregrense til en runder toppen (1609 i kartet) i 1500moh og går mot annen himmelretning. Her endres snødekket i stor grad, rim og hardere underliggende snø.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • Difficult to trigger • 1 - Small • Few steep slopes N, NE, NW between unknown masl and unknown masl • Det svake laget er blitt nedføyket av 1 cm DF

Avalanche Problems

• Dry slab avalanche • Buried weak layer of faceted snow beneath a crust • Within half a meter • A big and identifiable crystal in the weak layer. • Very difficult to trigger • 1 - Small • N, NE, NW above unknown masl

Avalanche Problems

• Buried weak layer of faceted snow near surface • Within a meter • Some steep slopes N, NE, E, SE, S, SW, W, NW between 1300 masl and 900 masl • Kantkornlaget trenger stor tilleggsbelastning. Kan være ett problem der snømassen over er tynnere

Avalanche Problems

• Dry slab avalanche • Buried weak layer of faceted snow near surface • Within half a meter • A big and identifiable crystal in the weak layer. • Very difficult to trigger • 1 - Small • Some steep slopes N, NE, NW between 1200 masl and 1000 masl • Vedvarende svakt lag ligger i toppen av snødekket, laget av kantkorn er 30 cm tykt og utgjør pr nå ikke en stor risiko. Mer snø oppå dette igjen vil kunne øke skredfaren.

Avalanche Problems

• Within half a meter • The overlying slab is soft. A big and identifiable crystal in the weak layer. • Few steep slopes N, NE, E, SE, S, SW, W, NW between unknown masl and unknown masl • Rimlaget ligger stort sett øverst i snøen, men i få bratte heng har det havnet fokksnø oppå som kan være ett skredproblem.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The weak layer collapses easily and clean (easy propagation). The collapsing weak layer is thin < 3 cm. The overlying slab is soft. • Easy to trigger • 2 - Medium • Some steep slopes E, SE above unknown masl • Nye vind på formiddagen har flyttet fokksnø til østlige og sørøstlige heng

• Dry slab avalanche • Buried weak layer of faceted snow beneath a crust • Within half a meter • The collapsing weak layer is thin < 3 cm. A big and identifiable crystal in the weak layer. • Difficult to trigger • 3 - Large • Some steep slopes N, NE, E, SE, S, SW, W, NW above unknown masl

Avalanche Problems

• Dry slab avalanche • Buried weak layer of new snow • Within half a meter • Difficult to trigger • 1 - Small • Some steep slopes N, NE, NW between 1200 masl and 1100 masl

Avalanche Problems

• Dry slab avalanche • Buried weak layer of new snow • Within half a meter • Difficult to trigger • 1 - Small • Some steep slopes N between 1200 masl and 1100 masl

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • A big and identifiable crystal in the weak layer. • W, NW • Kan bli et kommende skredproblem med mer vindtransportert snø oppå det svake laget.

• Dry slab avalanche • Buried weak layer of faceted snow near surface • The weak layer collapses easily and clean (easy propagation). A big and identifiable crystal in the weak layer. • Very difficult to trigger • 4 - Very large • Few steep slopes W, NW between 1200 masl and 1100 masl • Svært hardt lag av RG. Løste ved isolasjon i 19° helning. Kan kanskje fjernutløses på tynnere snøpakke.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of faceted snow near surface • Within half a meter • A big and identifiable crystal in the weak layer. • Difficult to trigger • 2 - Medium • Some steep slopes S, SW, W above unknown masl

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. • Easy to trigger • 2 - Medium • Some steep slopes E, SE, S above unknown masl • Utbredelsen av skred er ved de fleste heng i S/SØ.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of faceted snow near surface • Within a meter • The collapsing weak layer is thin < 3 cm. The overlying slab is soft. A big and identifiable crystal in the weak layer. • Easy to trigger • 1 - Small • Some steep slopes SE, S • Flak av fokksnø på overflaten som bryter lett på lag av kantkorn. Foreløpig lite binding i flaket - forventer kun små skred ved påvirkning av skiløper. Videre løsner blokken i bunn ved hard påvirkning.

Avalanche Problems

• N

Avalanche Problems

• Dry slab avalanche • Buried weak layer of faceted snow near surface • Within half a meter • The collapsing weak layer is thin < 3 cm. A big and identifiable crystal in the weak layer. • Difficult to trigger • 2 - Medium • E • Vanskelig å løse ut skred. På grunn av vinden lastes det snø i østlige heng og laget over svakt lag bygger seg opp med vindtransportert snø.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The weak layer collapses easily and clean (easy propagation). A big and identifiable crystal in the weak layer. • Easy to trigger • 2 - Medium • Few steep slopes E, SE, S, SW, W between 1300 masl and 900 masl • Laget er NEDFØYKA OVERFLATERIM, ikkje nedsnødd overflaterim slik det står, men det var den beskrivinga som var nærast. Eg har kun sjekka snøen i SV/ S /SØ men på grunn av tidlegare vær forventast problemet å ligge i alle himmelretningar. Nedbrytande prosessar har stor innveknad på om ein vil finne problemet eller ikkje. Der vinden har tatt vil ein ikkje finne desse krystallane ståande og det vil ikkje vere eit problem. Dermed kan ein og anta at ein ikkje finne SH i øvste del av fjellet. Einaste grunnen for at dette vil utgjere eit skredproblemet er om snø vil leggje seg som eit flak på toppen av SH laget. Dette vil då kun vere eit problem i få heng der krystallane fortsatt står samt at det er blitt transportert snø oppå krystallane. Ut i frå piten eg grov var ikkje dette eit skredproblem pga ingen snø på toppen av SH.

• Dry slab avalanche • Buried weak layer of faceted snow beneath a crust • Within half a meter • A big and identifiable crystal in the weak layer. • Easy to trigger • 2 - Medium • N, NE, E, SE, S, SW, W, NW between 1300 masl and 1100 masl • Det svake laget består av kantkorn under skarelag. Kantkorna er frå 2-2,5 mm store. Laget der brotet skjer er 4cm tjukt. Eg har kun sett på snølaga i S/ SV / SØ vendte sider, men mest truleg vil dette skredproblemet breie seg ut i alle himmelretningar ut i frå det været me har hatt den siste tida.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of faceted snow near surface • Easy to trigger • 2 - Medium • Some steep slopes SW, W, NW

Avalanche Problems

• Dry slab avalanche • Easy to trigger • 2 - Medium • Many steep slopes E, SE, S above unknown masl

Avalanche Problems

• Loose snow

Avalanche Problems

• Dry slab avalanche • Buried weak layer of new snow • Within half a meter • Easy to trigger • 2 - Medium • Some steep slopes E, SE, S, SW, W

Avalanche Problems

• Buried weak layer of faceted snow beneath a crust • Within a meter • The overlying slab is soft. • SE, S, SW • Vanskelig å påvirke. Se test.

• Buried weak layer of faceted snow near surface • Within half a meter • SE, S, SW • RGxf på 40-66cm

• Buried weak layer of faceted snow above a crust • Within a meter • A big and identifiable crystal in the weak layer. • SE, S, SW

Avalanche Problems

• Dry slab avalanche • Buried weak layer of faceted snow above a crust • Within a meter • A big and identifiable crystal in the weak layer. • Difficult to trigger • 1 - Small • Some steep slopes N, NE, NW

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. • Difficult to trigger • 1 - Small • S, SW between 1000 masl and unknown masl

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The collapsing weak layer is thin < 3 cm. A big and identifiable crystal in the weak layer. • Difficult to trigger • 2 - Medium • Few steep slopes S, SW between 1200 masl and unknown masl

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The collapsing weak layer is thin < 3 cm. The overlying slab is soft. A big and identifiable crystal in the weak layer. • 2 - Medium • Few steep slopes E, SE, S between 1200 masl and 1100 masl

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The weak layer collapses easily and clean (easy propagation). The collapsing weak layer is thin < 3 cm. A big and identifiable crystal in the weak layer. • Very easy to trigger • 2 - Medium • Few steep slopes S between 1200 masl and unknown masl

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The overlying slab is soft. • Very easy to trigger • 1 - Small • Few steep slopes S, SW between 1200 masl and unknown masl • Overflaterim beskyttet av tynt lag DF. Vil kunne skape problem ved lagdannelse på overflaten.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The collapsing weak layer is thin < 3 cm. A big and identifiable crystal in the weak layer. • Difficult to trigger • 2 - Medium • Few steep slopes S between 1300 masl and 1100 masl • Nedsnødd overflaterim, stående krystaller, ved nytt snøfall kan det forverre situasjonen.

Avalanche Problems

• Dry slab avalanche • Buried weak layer of surface hoar • Within half a meter • The collapsing weak layer is thin < 3 cm. A big and identifiable crystal in the weak layer. • Difficult to trigger • 2 - Medium • Few steep slopes E, SE, S, SW, W between 1300 masl and 1100 masl • Nedføyket overflaterim, stående rimkrystaller. Under et mykt RG lag. Skredfaren kan øke ved nytt snøfall.