“Spring is in the air” would be a common theme as we hit near record highs during our 8th AIARE 1 Avalanche Course of the season which concluded today. Despite the warm temperatures our snow-pack is certainly still dynamic as we got to experience a wide variety of conditions in the three days we spent together. Day 1 saw some productive morning discussions about different types of avalanches and avalanche terrain in general before heading outside for some great companion rescue practice.
Day 2 was VERY interesting as despite the warm temps it was very cold, clear, and calm the night before… so driving up to the Highland Center I was a bit excited to see obvious Near Surface Faceting all over the place from Bartlett to the Highland Center. I was even more stoked to see aggressive Surface Hoar all over the field right next to our classroom. I realized the warm temps and strong solar radiation expected would destroy it early so I grabbed some pics with my iPhone before class started.
While I have found small pockets before this stuff is a bit rare here in our windy “Arctic Maritime” snow climate and this was the largest area I have ever seen covered in it. Some of them measured 5mm in height, which is pretty impressive. An hour and a half later when we left the classroom to check it our the daytime warming and sun had destroyed it. I was glad to have the photos!
That afternoon we headed south along the east side of Mt. Willard and quickly noticed some huge “pinwheeling” from the strong solar radiation we where getting. I would call it “prolific” as it was everywhere. In some areas it looked like debris, but was just massive amounts of “pinwheels” and “rollerballs”. Some where quite big!
Other than just indicating strong solar radiation these little features can often preclude wet loose snow avalanches, and possible wet slabs if unstable conditions exist. On a slope covered in pinwheels Keith demonstrated measuring slope angle with his ski poles.
Minutes later we wrapped around to the more southern exposure of Mt. Willard and found fresh debris from a small slab avalanche that came down just to the right of Cinema Gully and almost reached the train tracks…
We finished the day looking at some layers on a small NW slope and found some buried Melt-Freeze crusts with free water sitting on top. Compression Tests were rather inconclusive.
Day 3 started at the Pinkham Notch Visitor Center. After accessing the bulletin we made a trip plan for Tuckerman Ravine.
At HoJo’s we chatted with Lead USFS Snow Ranger Christopher Joosen about the conditions and his and his fellow rangers job on the mountain, then we continued up the Tuck’s trail towards are original objective of Lobster Claw Gully.
We bumped into Frank Carus, another USFS Snow Ranger who pointed out an almost indistinguishable old debris pile that had come out of Lobster Claw the week before.
After some group discussion the majority voted to change our plan due to the strong solar radiation and warm temps possibly making things a bit iffy on the right side, and fell back on our more conservative plan to head over towards Left Gully and The Chute. The decision was made to spread out when crossing the main run-out.
We got a good vantage to see the debris and the crown at the top of Right Gully from the skier triggered avalanche the day before.
We chose the slope between Left Gully and The Chute to poke around. We got some super positive hand shear results on a 25cm pencil hard slab sitting on graupel that was mentioned in Friday’s bulletin. That got us excited to dig further and we got tons of positive CT results along with a RB4, MB. A student sent me this video of the Rutchsblock.
I’ll upload the hand shears and Compression Tests later.
After we descended via Little Headwall and Sherburne we had a good course close back at PNVC. I stuck around for the annual NH Search & Rescue dinner and a great presentation by the Director of Summit Operations, Cyrena-Marie Briede, on her work in Alaska.
More to come on this event, along with the videos from the Handshears, CT’s, and Rutschblock tests so please check back!