Avalanche Forecast

On Tuesday, a frontal system will bring a cool down with new snowfall accumulating above 5000-5500 ft by the afternoon. You may still trigger Loose Wet avalanches or they may be triggered by additional rainfall Tuesday morning. Watch for signs of wet snow conditions such as sluffing, roller-balling and any natural Loose Wet avalanches as signs of an increasing hazard. Loose Wet avalanches still have the ability to become large in areas where they gouge down to deeper layers of moist or wet snow. 

Shallow new Wind Slabs may form on lee slopes above treeline by the afternoon. Use visual clues such as fresh cornices, wind drifted pillows and cracks in the snow all indicating that you could trigger a Wind Slab avalanche. 

Large fresh cornices will still be fragile due to recent warm temperatures and initial rainfall Tuesday morning. Give cornices a large margin of safety and avoid travel on slopes below, as cornice failures may trigger large avalanches on slopes below.

Minimize or avoid exposure below unsupported slopes as the potential for Glide Avalanches will increase during prolonged rainfall and warm temperatures. 

Monday was warm with filtered sunshine. The dry weather followed the strong weekend storm that caused rain Saturday to high elevations followed by cooling and deep new storm snow of 1.5-2 ft over the Mt Hood area by Sunday afternoon. There will be a strong difference on new snow amounts with elevation as temperatures were near freezing in the lower terrain below treeline. The new snow was transported by periods strong or very strong winds that built fresh Wind Slabs on a variety of aspects, especially below ridges. The recent storm built fresh cornices along exposed ridges. 

Periods of rain and a rising snowline allowed wet snow conditions to extend to near and above treeline Thursday and Friday.  A series of crusts and moist or wet snow exist in the upper snowpack.  

There are currently no significant layers of concern in the mid or lower snowpack.

Observations

During morning mitigation work Monday, Mt. Hood Meadow Pro-patrol reported that the new snow was not very sensitive to ski triggering. Explosives produced generally shallow soft slabs, with a few that were up to 1-2 ft deep on lee slopes near treeline. 

Mt Hood Meadows pro patrol reported 8 inch average soft slabs being easily released with ski cuts during avalanche control Sunday morning. In lower elevation terrain from 4500-5400 ft, the new storm snow of 10-14 inches was very reactive to ski trigger with avalanches running long distances and gouging into old wet snow.