Bulletin d’avalanche

Provo

Utah Avalanche Center
Voir sur la carte

Danger d’avalanche

  • Alpin
  • Limite forestière
  • Sous la limite forestière
Open full map
Périmé — ce bulletin a expiré 8 years ago. Vous consultez des conditions passées, pas le bulletin en cours.

Points saillants

The avalanche danger is HIGH at the upper elevations and CONSIDERABLE at the mid and lower elevations. Warm temperatures, strong winds and heavy wet snow have created dangerous avalanche conditions.

--Careful snowpack evaluation, cautious route-finding, and conservative decision making are essential for travel in the backcountry.

--Avoid avalanche terrain and avalanche runout zones such as gullies and couloirs.

---The avalanche danger will spike during periods of heavy snowfall or increased winds - natural avalanches will become likely.

--Provo mountain avalanches run long distances due to the steep terrain.

Problèmes avalancheux

  • Wind Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Very Likely
    Taille
    3

    24 hours of moderate to strong winds have drifted the snow at mid and upper elevations. On the shadier, northwest through south easterly facing slopes, the new drifts will be sitting on weak, sugary snow. It will be possible to trigger these new drifts from a distance or from below. Human triggered avalanches likely, failing at the old snow surface or perhaps within the storm snow. Any new cornices along the upper and mid elevation ridgelines will be very sensitive today. Give them a wide berth - travel well back from the edges and avoid travel beneath them.

    Even out of the wind, the new snow may not have bonded well to the variety of old snow surfaces, consisting of crusts and preserved sugary facets. Or slides may fail with in the new snow on a mid storm weakness or where there are pools of graupel. Even a shallow new snow slide will pack a punch, due to the dense snow.

  • Loose Wet

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely
    Taille
    2

    With the rain/snow line around 7,000’ for much of the night, the wet soggy snow will need time to cool. It will be possible to trigger wet, loose sluffs today on all low elevation slopes and on low and mid elevation slopes. Avoid travel in steep gullies and couloirs, including ice climbs. Even a small wet sluff in a steep terrain trap such as a creek bed or road cut can pile up cement like debris deeply.

  • Persistent Slabs

    • Alpin
    • Limite forestière
    • Sous la limite forestière
    Probabilité
    Likely
    Taille
    3

    The various faceted weak layers in the snowpack may become active once again today, especially in shallow snowpack areas. Examples are slopes that have slid one or more time this year and odd areas such as Lambs, No Name or Snake Creek, with traditionally shallow snow packs. A smaller new snow slide or wind slab could trigger one of these deeper weak layers, producing a large avalanche

Special Announcement

Check out a new blog post - The Risks and Rewards of Ski Patrol - A Conversation with Jake Hutchinson.

Recent Activity

A significant natural wet loose avalanche cycle occurred on northerly facing slopes in Santaquin Canyon and the lower couloirs in Little Cottonwood, occurring before it rained. It surprised me, but the simple combination of clouds and warm temperatures was enough to heat the facets and trigger these slides. Santaquin avalanche below, photo by Luke. Santiquin observations HERE and HERE.

There was a very close call in the northwest couloir on Timpanogos - a wind slab broke on the 3rd person, who fought and got out to side and grabbed tree. As the slide ran down, it broke out another 2-3 foot deep crown 600’ below. We’re assuming it broke on a sugary, faceted weak layer. There were other reports of shallow wind slabs breaking on facets. Photo below.

Snow and Weather

The warm, wet storm left behind 2 to 6” of heavy, dense snow with up to an inch of water content. There will rain soaked snow at the bottom of the new snow at the mid and low elevations, but the graupel laden snow should be drier near the top. The south to southwesterly winds were moderate to strong for the last 24 hours, maxing out with 30 to 40 mph averages, and gusts to 60 mph.

Currently, it's snowing heavily in the Provo area mountains, and the southwesterly mid elevation winds are averaging 25 mph, with gusts to 40. An additional 4 to 8 inches of snow are possible today. West to southwesterly winds will be in the 20 to 30 mph range, with gusts to 40 mph. Speeds will increase again this afternoon, and high ridge lines could average 25 to 35 mph, with gusts in the 50s and 60s. Temperatures will warm into the mid 20s to mid 30s.

General Announcements

CLICK HERE FOR MORE GENERAL INFO AND FAQ

This information does not apply to developed ski areas or highways where avalanche control is normally done. This forecast is from the U.S.D.A. Forest Service, which is solely responsible for its content. This forecast describes general avalanche conditions and local variations always occur.

Régions couvertes