Wet Slab in Fresno Bowl

AVALANCHE OBSERVATION
Fresno Bowl, Outside of the Mammoth Mtn Ski Area Boundary

Drainage:

Submission Info
Clancy Nelson
Forecaster
Saturday, April 7, 2018 - 2:30pm
Red Flags: 
Recent avalanche activity
Recent loading by new snow, wind, or rain
Avalanche Type: 
Wet
Slab
Trigger type: 
Natural
Crown Height: 
3 ft
Aspect: 
Southwest
Weak Layer: 
Old Snow
Avalanche Width: 
500ft.
Elevation: 
10 200ft.
Bed Surface: 
Old Snow
Avalanche Length: 
3 000ft.
More detailed information about the avalanche: 

This avalanche occured outside of the Mammoth Mtn Ski Area boundary in Fresno Bowl, likely during the rain event on 4/7. R3.5/D3.5. Crown was 30” avg, 40” max. Ran approximately 3000’ with four distinct lobes, the widest was approx 500’. The lowest lobe was on a 10-15 degree slope. The center of the gully looked like a mud slide, so sections obviously ran to the ground. But the bed surface on all 4 of the lobes was old snow, possibly a sun crust. 

This slide occured naturally in an area where avalanches are not mitigated. Remember that EVERYTHING beyond the ski area boundary is backcounty. "Side country" is backcountry.

Thank's the MMSP for the report.

Avalanche Photos: 
Air temperature: 
Precipitation: 
Air temperature trend: 
Wind Direction: 
Accumulation rate: 
More detailed information about the weather: 
37° 37' 41.2788" N, 119° 2' 18.1212" W

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