Tetons

The avalanche hazard will start at Low this morning and increase in the afternoon as temperatures in the mountains rise above freezing. This morning, while the hazard remains Low, it is still possible for skiers and riders to trigger small isolated pockets of wind slab avalanches on steep slopes above 9,000 feet. Then in the afternoon, it will be possible for a person to trigger wet snow avalanches on steep slopes, and wet slides could also occur naturally on steep rocky terrain in direct sunlight. While these slides will start small, probably less than a foot in-depth, the debris could become entraining and destructive. Backcountry travelers should evaluate terrain as even small slides could have dangerous outcomes if triggered above terrain traps, cliffs, or on steep sustained slopes. A reminder from Grand Teton National Park that the winter wildlife closures to protect and provide critical habitat from native bighorn sheep continues through April 30. For more information on these closures please refer to their website.https://www.nps.gov/grte/learn/management/wildlife-closures.htm

A dry air mass and ridge of high pressure will continue to dominate the weather pattern through the weekend. A shortwave system passing across the northern Rockies may bring some high clouds to the areas tomorrow through Saturday. Overnight temperatures are expected to drop into the low 20s at the upper elevations and mid-20s in the valleys. Then as the day warms, mountain temperatures will range from the 40s to 50s and valleys will climb into the 50s to 60. Southwesterly ridgetop winds will continue to be 10 to 20 miles per hour. In all the forecast areas, the wet snow avalanche hazard will start Low and then increase as the day warms. As crusts break down and snow surfaces become wet, it will be possible for a person to trigger a wet snow avalanche on steep avalanche terrain. Depending on the duration of the overnight freeze, will determine how quickly the snowpack loses cohesion. On steep solar slopes, natural-triggered small wet loose slides will be possible as well as cornice failures. Wet snow can quickly change from stable to unstable and as this occurs, steep avalanche terrain should be avoided. In the Togwotee Pass Forecast area above 10,000 feet, the dry snow avalanche hazard will be Moderate in the morning. On some slopes, a person could trigger a large persistent slab avalanche one to two feet deep. Careful evaluation of the snowpack will be needed to assess this problem.