Northern Madison

Found some reactive fresh windslabs that were on northeast terrain  features yesterday Wednesday 4/9 easily triggered with a very small cornice we dropped in the northern Madison range, the pocket slabs didn’t propagate super wide but did pack a punch and were up to 1 ft deep.

We snagged an early morning tour to avoid the heat today and it (mostly) worked. We saw no avalanches, cracking or collapsing while out. 

-We found a 2-4cm thick breakable crust on SE, S, SW, and W aspects that probably formed during Friday’s sunshine capping 6-10” of fresh snow above 9k’

-There was much less fresh snow below 9k’ (baked off?)

-Northerlies held stable soft snow!

-Small natural dry loose activity started around 11am on steep NE and E slopes initiating from around rocks/trees

-We sniffed out some south facing corn, but it was generally grabby/sloppy wherever a few inches of recent fresh snow remained

The slope at the my skis broke about 15-20 meters wide and 15 cm deep at the flanks to 40cm deep in the gut, SS-ASu-R1-D1.5-I-M(L)-TK. About 30 meters downhill, the slab rode up onto the new snow and ran out of momentum before reaching the runout. Photo: J Negri

Skied around Beehive Basin today; there was lots of new snow and very little wind effect. Skied into the top of Bear Basin from Beehive by going up going home and down the east side, right-side-up powder skiing. While descending Island Boy into the South Fork of Spanish Creek, we had similar 60-100 cm of right-side-up new snow on a heavily textured melt-freeze layer of old snow. Felt the snow density stiffen up from light low density snow around 300 meters down the ski line so cut to the left into a safe zone, the slope at the my skis broke about 15-20 meters wide and 15 cm deep at the flanks to 40cm deep in the gut, SS-ASu-R1-D1.5-I-M(L)-TK. About 30 meters downhill, the slab rode up onto the new snow and ran out of momentum before reaching the runout. Right where the slope broke, we had wind wrapping around the north ridge cross-loading the couloir (skiers left to right), downslope, and on skiers' right of the line, there was no evidence of wind transport. Skied the rest of the line and looped back into Beehive with no other excitement. 

We rode Buck Ridge through First Yellowmule, Buck Creek, Second Yellowmule and into McAtee Basin. Pulses of snow through the day dropped an inch or two by the time we left. Light winds, no avalanches, and no signs of instability to report. The measured storm total above the melt-freeze crust was 11" (1.3" of SWE) at the top of 1st Yellowmule. The snow was well bonded to the underlying surface. Quick pits testing the snow above the melt-freeze crust yielded no indicators of instability. 

The riding was quite nice other than the lowest section of the Doe Creek Road is melted out. It was fine on the way in, but very muddy on the way out. 

Triggering an avalanche is unlikely UNLESS:

1. The wind picks up to speeds capable of transporting snow. 
2. The temperatures increase or slopes get hit by the warm spring sun. 
3. There is another significant pulse of snowfall. 

We skinned up to the Beehive-Bear ridgeline, down into Middle Basin, up Middle Peak and returned the way we came. 

It snowed on and off all day, with little accumulation and patches of sunshine mixed in. Winds were moderate at ridgelines and light-calm lower down. During the periods of sunshine we had good views into Beehive and middle basin. We saw no recent avalanches or signs of instability. 

There were 10-12" of new snow from the last couple days above firm crusts. The new snow had bonded well to the crust. We encountered a little wind drifting at the ridgeline, but it hadn't formed much of a windslab. Loose dry sluffs were the biggest hazard we encountered. The little bit of sunshine densified the snow surface and caused roller balls, but wasn't enough to increase the hazard. 

Winter conditions in middle basin. Cracking in wind drifted pockets at the top of bat ears couloir and at the top of middle peak. Snowing hard all afternoon nearly filling in our skin track by the time we exited.