menu
print

Mt Hood

Issued: 8:43 AM PST Wednesday, February 7, 2018
by Robert Hahn

NWAC avalanche forecasts apply to backcountry avalanche terrain in the Olympics, Washington Cascades and Mt Hood area. These forecasts do not apply to developed ski areas, avalanche terrain affecting highways and higher terrain on the volcanic peaks above the Cascade crest level. 

Updated 8:40 AM: Warmer than forecast temperatures Wednesday resulted in an update include loose wet avalanches in all elevation bands on the west slopes of the Cascades and to add the problem near and below treeline on the east slopes. Lower-than-forecast wind speeds have resulted in a reduced wind slab hazard in both the Cascade West-North zone and Cascade East-North zone above treeline. The potential for wind slab development has been reduced and the anticipated hazard has been reduced accordingly from considerable to moderate.

It will be possible to trigger a loose wet avalanche during solar heating on Wednesday. Avoid steeper solar slopes if wet surface snow becomes deeper during the afternoon hours and don't expose yourself to cliffs or terrain traps such as gulleys.

Danger Scalei
  • No Rating
  • Low
  • Moderate
  • Considerable
  • High
  • Extreme

Avalanche Problems for Wednesday

Loose Weti

Loose wet avalanches occur where water is running through the snowpack, and release at or below the trigger point. Avoid terrain traps such as cliffs, gullies, or tree wells. Exit avalanche terrain when you see pinwheels, roller balls, a slushy surface, or during rain-on-snow events.

  • Avalanche Problemi
  • Aspect/Elevationi
  • Likelihoodi
  • Sizei

Forecast for Wednesday:

Continued very warm and warming temperatures along with partly cloudy skies will increase the possibility of loose wet avalanches on Wednesday.

The thick 10-12" crusts formed on Monday (1/5) will take time to melt, but as freezing levels continue to rise and the sun adds energy to further melt the snow, expect boot penetration to increase and enough wet snow will thaw to make triggering a loose wet avalanche possible. At all elevations, avoid steeper solar slopes where wet, slushy snow becomes deeper than a few inches.

Avalanche Summary:

Warming aloft created inversion conditions on Tuesday, but all elevations warmed above freezing by afternoon, allowing previously firm crusts an initial opportunity to thaw. Low clouds were seen near the top of the inversion.

Cooling from Sunday afternoon through Monday refroze the top 10-12" of wet surface snow into a firm crust.

Moderate to strong W-NW winds were seen over the weekend at Mt. Hood, but due to continued mild conditions, there is no snow available for transport in the above treeline band (NWAC's forecast does not apply above 7000-8000 feet). The mild and at times wet weather created wet snow conditions well into the above treeline terrain in the Mt Hood area. 

The upper snowpack consist of a mix a thick crust at the surface, wet snow, old crusts, and well consolidated storm snow. 

Observations

Mt. Hood Meadows pro patrol reported that wind kept the snow firm except at the lowest elevations receiving solar heating. Runnels were in the terrain up to 7300'.

Mt. Hood Meadows pro patrol reported that Friday's widespread wet loose avalanche activity had become more stubborn and isolated near and below treeline by Saturday.  The wet upper snowpack was still quite unconsolidated with the most recent 1/18 crust breaking down due to the sustained mild wet weather. Winds were strong near and above treeline but no snow was available for transport in area. 

No Corresponding Mountain Weather Forecast Available

USE AT YOUR OWN RISK

This Backcountry Avalanche Forecast is provided in conjunction with the US Forest Service, and is intended for personal and recreational purposes only. Safe backcountry travel requires preparation and planning, and this information may be used for planning purposes but does not provide all the information necessary for backcountry travel. Advanced avalanche education is strongly encouraged.

The user acknowledges that it is impossible to accurately predict natural events such as avalanches in every instance, and the accuracy or reliability of the data provided here is not guaranteed in any way. This forecast describes general avalanche conditions and local variations will always occur. This forecast expires 24 hours after the posted time unless noted otherwise.