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Thunder Mountain Northwest Slopes 

Thunder Mountain Northwest Slopes 

Type:  Alpine, 2400', Grade II
Original: Mod. Snow [details]
FA: n/a
Season: Winter most years
Page Views: 359
Submitted By: Justin Johnsen on Jan 10, 2012

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BETA PHOTO: The bend north from Big Butch Wash to the bottom o...


This is a nice local spot for Los Angeles area residents to practice their winter mountaineering fundamentals. Some winters there won't be enough snow to bother with this. Follow the local weather and trip reports and you'll find the sweet days.

From the road, follow Big Butch Wash east/northeast up a moderate snow slopes. Watch out for occasional descending hazards: boulders from the steeper couloirs above, or off-piste snowboarders and skiers shredding down the wash from Thunder Mountain.

A crux is at the top of the wash, where the route turns north and goes up a short, steep hump that leads to a level valley. From there, a number of options can take you up the northwest slopes of Thunder Mountain to the summit, including a series of shallow gulleys and ridges.


Park on the right-hand side of Mt. Baldy Road around 6,200 ft of elevation: past Manker Flats, but before the ski lift parking lot. A USFS Adventure Pass is required throughout the area. On winter weekends with good snow conditions, you may find the area next to the road quite busy.


General mountaineering ice axe and crampons, poles and snowshoes, and/or avalanche precautions, depending on conditions.

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By Benjamin Chapman
From: Small Town, USA
May 2, 2012 parking permit is required, but the infamous Adventure Pass, which is a tool the USFS uses to collect revenue from "forest users."
By Justin Johnsen
From: Nor Cal
May 14, 2012

Thanks Benjamin, I fixed the description!


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