Max slope angle
30-45 Degrees
Primary aspect
South facing
Vertical descent
5,400.00 ft (1,645.92 m)
10.00 mi (16.09 km)
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Arguably one of the easiest Cascade volcanoes to climb, Mount St. Helens also provides one of the best ski descents in the Cascade Range. On a warm spring day, the southern exposed Worm Flows route becomes prime-time corn skiing.  The route is best completed with good visibility, as most of the route and the best skiing are well above tree line.

Beginning at the Marble Mountain Sno-Park, Worm Flows is the primary winter route, as the road to the Climbers Bivouac is not plowed during the winter. The sno-park is also a hub for snowmobile traffic in the area, so don't expect peace and quiet if you plan on camping in the lot to get an early start. The route winds through a well-used network of cross-country ski trails before meeting the Worm Flows just above tree line. The Worm Flows get their name from the worm-like features that extend down the southeast flanks of the mountain.

Above the tree line the winter route is yours to choose, and the lava flows create small canyons and ridges that are easy to follow. The ridges are often the best to skin-up, while the small canyons offer protected snow that often makes for better skiing. The route primarily follows the fall line, and it is easy to follow with good-visibility. The last 1,000 feet is a large and gentle bowl that will usually require a switchback or two as the route approaches the summit rim. The true summit sits west of where the Worm Flows route meets the crater rim, but few skiers put in the extra half-mile to reach the true summit.

The ski down offers 4,000 feet of uninterrupted fall line skiing that will quickly make you forget about the ascent. Flowing features and small canyons add some excitement to the relatively straightforward ski. Be aware of wind loaded bowls and terrain traps, as avalanche risks are a main concern during the winter months. Once you reach the tree line, you'll be able to ski your skin track all the way to the car with a few pushes.

Climbing permits are required from November 1 through March 31, but they are free of charge and can be found at the Marble Mountain Sno-Park.

Logistics + Planning

Parking Pass

Sno-Park Parking Permit (required in OR + WA 11.01 thru 04.30)


Corn skiing. Great views.


Some snowmobile traffic. Weekend crowds.

Trailhead Elevation

2,700.00 ft (822.96 m)

Typically multi-day


Shuttle required



Nearby Adventures

Mount St. Helens National Volcanic Monument
Mount St. Helens National Volcanic Monument
Southwest Washington/Mount St. Helens, Washington

Nearby Lodging + Camping

Southwest Washington/Mount St. Helens, Washington
Southwest Washington/Mount St. Helens, Washington
Southwest Washington/Mount St. Helens, Washington


Super great visibility on this trip, easy route finding and great snow. Fun to Bivy in the parking lot and saw some people camping farther up which looked great too. Actual route was probably west of Worm Flows and we slogged to the higher summit area mentioned in the above trip report. Great views all around. The ski down was fun with crusty snow at the top due to wind, good corn snow in the middle, and wet loose snow at the bottom.

Note: it was about a mile and a half walk on dirt (easy trail) until there was enough snow to skin. A few spots required taking off skis to get over rocks or dirt farther up.
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