Good morning. This is Mark Staples with the Gallatin National Forest Avalanche Advisory issued on Thursday, March 28 at 7:30 a.m. A Montana Fish, Wildlife & Parks Recreation Trails Grant sponsors today’s advisory. This advisory does not apply to operating ski areas.
Yesterday many places had high temperatures in the high 30s to low 40s F with light winds. Temperatures dropped to the mid to low 20s F overnight and winds were blowing 5-10 mph gusting to 15 mph from the W and SW this morning. Today’s weather will be similar to yesterday’s with warm temperatures, light winds, and mostly sunny skies. Some snow will fall Friday afternoon followed by a brief period of slightly cooler temperatures.
Bridger Range Madison Range Gallatin Range
Lionhead area near West Yellowstone Cooke City
There are two concerns today: wet loose snow avalanches (video) and falling cornices. Fortunately the snow surface refroze well last night and should act predictably today. The snowpack often provides clues that the wet snow avalanche danger is rising. Watch for growing pin wheels rolling downhill – a sign of decreasing stability. The key to avoiding loose, wet snow avalanches is riding on slopes as soon as they soften but getting off them before they get too wet and produce avalanches.
Yesterday while ascending a long couloir, my partner and I closely monitored small south-facing slopes hanging above us. Even a small, wet loose snow avalanche falling into the couloir could have caught us and caused trouble. Unlike loose, wet snow avalanches, cornices are unpredictable. They are very large this time of year. Look for them and identify where they will fall if they break. Avoid these zones or cross under them as quickly as possible.
On many north-facing slopes, dry snow, good skiing and good riding can be found. Although generally safe avalanche conditions exist in these places, don’t turn off your avalanche radar. Small avalanches like a few recent ones near Cooke City can still occur (photo).
For today the avalanche danger will start at LOW but possibly rise to CONSIDERABLE as warm temperatures and sunshine melt the snow surface.
I will issue the next advisory tomorrow morning at 7:30 a.m. If you have any snowpack or avalanche observations drop us a line at mtavalanche@gmail.com or call us at 587-6984.
Take Note:
Our 136th and last avalanche advisory will be on Sunday, April 7th.