Mar 1, 2014 @ 7:32 am

Special Avalanche Information for March 1, 2014

High winds and continued heavy snowfall have created HIGH AVALANCHE DANGER conditions in the Rattlesnake and the southern Swan and Mission Mountains north of Missoula.  This special update also includes the foothills areas close to Missoula as well as Mount Jumbo and Mount Sentinel. The avalanche danger is HIGH on any open slope steeper than 30 degrees.

The avalanche danger in the Bitterroot mountains on wind loaded terrain steeper than 30 degrees is CONSIDERABLE. South facing slopes here also developed a sun crust earlier this week so with east to north winds expect these aspects to get loaded.

This is Steve Karkanen from the West Central Montana Avalanche Center with a special avalanche information update for Saturday March 1, 2014.


Strong east winds and heavy snowfall associated with a blizzard in the Missoula valley have created very dangerous avalanche conditions on Mount Jumbo, Mount  Sentinel and other steep open slopes close to Missoula.  A large slab avalanche was triggered by a snowboarder near the top of Mount Jumbo yesterday afternoon.  The avalanche ran to the valley floor, destroyed two homes and buried 3 people. A large rescue effort consisting of local first response teams, law enforcement, Search and Rescue personnel and at least 100 nearby residents quickly mobilized to assist with search efforts.  All 3 victims were found alive and transported to local hospitals.

The City of Missoula Police and Fire Departments are conducting an investigation  into this tragic event.

Our thoughts are with them and their families hoping for a speedy and full recovery.  Many thanks to everyone involved in this complicated rescue.


Weather and Snow

Warm temperatures and sun Tuesday and Wednesday created a hard ice crust which is now a perfect bed surface for avalanches. Blizzard conditions in the valley have formed sensitive storm slabs and wind slabs on a variety of aspects. Any open terrain steeper than 30 degrees that has been recently loaded should be avoided.  Many people reported to us Friday that they triggered wind slabs and experienced collapse and fracture propagation in areas loaded by the wind on Mount Sentinel.

It has been many years since Missoula has seen a full-on blizzard with this much snow. High winds are expected again today and will continue to load these low elevation slopes. Please respect these conditions and avoid Mount Jumbo and the steeper slopes of Mount Sentinel for a few days.

The backcountry of the Bitterroot Mountains has not received the heavy snowfall seen in the Rattlesnake or Missoula valley. Mountain winds have been fairly calm until late yesterday when east winds reached the higher elevations. This morning on Point Six, east winds are topping out at 61 mph! The temperature is -21 for a wind chill value in the negative 60 degree range.  I would expect to see high ridgetop winds throughout the Bitterroot today as this arctic air takes hold.


Weather and Avalanche Forecast

The Weather Service is forecasting east winds of up to 50 mph to continue thru this morning. The heavy snow has moved out of the area but we can expect ANOTHER round of heavy snowfall starting Sunday night. This storm may be much wetter and warmer than what we current have which will only make avalanche danger conditions worsen.

The next regular avalanche advisory will be issued by Dudley Tuesday morning however we will post information updates as needed.




This information is the sole responsibility of the Forest Service and does not apply to operating ski areas. The avalanche danger rating expires at midnight tonight but the information can help you make a more informed decision regarding travel in avalanche terrain for the next few days.

Our advisory area includes National Forest System lands in the Bitterroot Mountains from Lost Trail Pass north to Granite Pass, the Rattlesnake Mountains north of Missoula and the Southern Swan and Mission Mountains near Seeley Lake, MT. Avalanche information for the Lookout Pass/St. Regis Basin area is available from the Idaho Panhandle Avalanche Center.