Numerous large and very large natural avalanches were observed on Sunday after 11″ of new moist snow with 2″ of SWE from SSW,SSE,W winds gusting 20-40 mph for 24 hours. Pictures from Sundays Easter Avalanche Cycle are available HERE.
No new avalanches have been observed or reported since Sunday. Even though most of HP is inaccessible right now, we still believe that no recent avalanches have occurred since Sunday.
Below are more natural avalanches from Easter Sunday 4/4
|Signal Word||Size (D scale)||Simple Descriptor|
|Small||1||Unlikely to bury a person|
|Large||2||Can bury a person|
|Very Large||3||Can destroy a house|
|Historic||4 & 5||Can destroy part or all of a village|
Small winds slabs 1-3″ thick will be unlikely in most locations, but possible to human trigger in isolated locations on SE to S to W aspects at upper elevation today. For the most part, HP was spared by the loathed yet anticipated wind on Friday. Moderate winds gusted 20mph for 4 hours from the E and NW at 3500′. Limited information is available above 3800′ due to the road being closed.
This problem will be quick to heal.
Even though the persistent slab is not expected to be a problem today, it is impossible to go through a forecast without talking about it. Below are pictures showing the depth of the buried “facet crust sandwich” weak layer that was the culprit for Sundays Easter Avalanche Cycle. Test results this week have showed low to moderate propagation on this layer. Any additional loading will activate the persistent slab problem again.
HP received a trace of snow overnight. Temperatures have remained very cold this week remaining in the single digits and teens. Temps are -7ºF at 3505′ at 7am this morning. Since Thursday, the high at 4500′ has been 13ºF and the low -7º F. Winds have been calm to light out of the East with light to moderate gusts from the east at 4500′ since Thursday. Today wind will be 1-7mph from the east at 3000′.
Clouds will move into HP today with no significant snowfall in this next pulse of weather. However, winds are expected to increase from the Southeast up to 25 mph Sunday increasing to 45 mph Monday morning. Another storm will be on the heels of this event, potentially bringing more moisture mid-week, but it is too far out to be confident at this point.
NWS Rec Forecast here.
NWS point forecast here.
State Parks Snow Report and Motorized Access information here.