Worm Flows, Winter Climbing Route


Area Status: Open
Winter Climb2

The Worm Flows Climbing Route is the primary route used by climbers during the winter and early spring to reach Mount St Helens Summit. Worm Flows is the most direct route to the summit of Mount St. Helens during the winter season. Ice axe, crampons, and avalanche awareness are recommended on this route. Skis with climbing skins or snow shoes with cleats are also highly recommended.

From the Marble Mountain Sno-Park use the Swift Ski Trail, #244 to reach timberline. Cross to the west side of Swift Creek, just above Chocolate Falls (elev. 3,700'). Follow ridges and open slopes to the crater rim. Wooden route marking posts guide climbers from timberline to approximately 4,800' elevation. Round trip is approximately 12 miles, with total time round trip being approximately 7 to 10 hours. To reduce your exposure to avalanche potential, stay away from snow loaded slopes and gully bottoms. Stay off the cornices at the crater rim.

Climbers should be prepared for winter climbing conditions. Sign in at the register and sign out on your return.

 Two websites to help plan your trip are: Northwest Avalance Center West Slopes South and Mountain-Forecast.com.

Mount St. Helens Summit Information.

⚠️ Important Alert: (07/11/24): The cornice has cracked and fell into the rim on 4th of July weekend, in addition to taking part of the rim with it. This now leaves a very dangerous 15 foot section that allows for a tempting view into the crater. While very tempting, the structure of the rim is extremely unstable and is continually being undermined by constant rockfall. More of the rim will give way with this rockfall activity. Do not step out on this section of the rim to look into the crater. Treat it like an ice cornice and stay at least 30 feet back.

On March 30th, a climber fatality occurred due to a partial cornice failure after someone stepped out onto the cornice edge. A dangerous cornice, an overhanging mass of snow formed by wind, grows through the winter on the leeward side of the wind exposed edge of the summit and crater. As it grows, the cornice can hang quite a distance over the edge, making it fragile and extremely dangerous to walk upon to get a view into the crater. Stay back at least 30 ft (9 m) from the visible edge. There may not be any flagging stakes or markers indicating the danger zone, so use extreme caution. The high summit drift may prevent you from having any view over the rim to the North. Always check current conditions before your climb.    

Click here to read the most current climbing conditions from Mount St. Helens Institute. 

At a Glance

Current Conditions:  07/11/24: ALERT! The cornice has cracked and fell into the rim, in addition to taking part of the rim with it. This now leaves a very dangerous 15 foot section that allows for a tempting view into the crater. While very tempting, the structure of the rim is extremely unstable and is continually being undermined by constant rockfall. More of the rim will give way with this rockfall activity. Do not step out on this section of the rim to look into the crater. Treat it like an ice cornice and stay at least 30 feet back.
  • Safety Alert: A cornice (giant, overhanging mass of snow) forms every year at the summit and can release at any time, plunging into the crater. Stay well back from the edge and don't trust footprints you see. 
  • Pack out your trash, please. Please bring your own blue bags due to limited supply at the trailhead.
  • Please do not congregate at the summit or in the parking lot.
  • Check Avalance Risk Levels often before your climb!
Reservations: Between April 1 & Oct. 31 climbing permits are limited in number and purchased online in advance.  
Fees:
Permit Info: Mount St. Helens Climbing Permits are required year-round for each person and each day they will be traveling above 4800 ft elevation on the slopes of Mount St. Helens.
  • April 1- Nov. 30: Climbing permits are limited and must be purchased online in advance at Recreation.gov. Permits will be released one month at at time for purchase
  • December 1- March 31: Permits are free and available at the Marble Mountain Sno-Park kiosk.
Washington State Sno-Park Permit required December 1 to March 31. Permits not available on-site. Purchase in advance or from a vendor. No other pass required during Sno-Park season
Usage: Medium
Best Season: Winter/Early Spring
Busiest Season: Winter/ Early Spring
Restrictions: Snowmobiles are restricted in the Non-motorized zone, the climbing areas between Monitor Ridge and the Worm Flows.
Closest Towns: Cougar, WA
Water: No
Restroom: Vault Toilets at Marble Mountain Sno-Park
Information Center:

General Information

Directions:

From Cougar, WA drive east on Lewis River Road, which turns into Forest Road 90. Continue on Forest Road 90 until the intersection with Forest Road 83. Turn left on Forest Road 83 and continue approximately 6 miles to the Marble Mountain Sno-Park. During the winter and early spring Forest Road 83 is gated at the Sno-Park.


General Notes:

Know Before You Go:

Some Cornices (overhanging snow) on the Crater Rim of Mount St. Helens are unstable and prone to sudden failure. Extreme caution is advised! Do not approach the crater rim unless you can find a wind-scoured area where the surface of the rim is visible. The crater rim is unstable and is subject to frequent rockfall and collapse.

Stay back from the crater edge, it is potentially hazardous at any time of year (especially during the period of elevated avalanche danger and rockfall during the spring thaw).

Winter/early Spring Climbing Tips from a Mountain Steward.

Climbing Preparation and Safety Information

  • Climbing Safety
  • Climbing Essentials
  • Active Volcano Hazards
  • Hypothermia/Altitude Sickness

Parking:

Weekends can be busy.


Activities

Mountain Climbing

Related Information

Recreation Areas

Recreation Activities

Location

 
  Elevation : 
2,800 ft. - 8,364 ft