Avalanche Forecast for Saturday, March 28, 2020
This information was published 03/28/2020 at 7:00 AM.
The Bottom Line
Generally safe avalanche conditions exist today as avalanches are unlikely. If skiing avalanche terrain today, practice careful sluff management to ensure you don’t get pulled somewhere unwanted. In addition, there may be overhead hazards in the form of other people, as well as folks below that should be kept in mind when managing sluff. With spring conditions expected in places today, remember that slopes can take time to soften and also can refreeze quickly: crampons and an ice axe are great to have early and late in the day to help mitigate the long, sliding fall. Avalanche danger is LOW.
On Friday, March 27th, NH Governor Chris Sununu joined all other New England states in issuing a stay at home order for the State of NH in order to limit the spread of a pandemic. Violating this order potentially spreads the illness through the public, USFS Snow Ranger staff and volunteer rescue teams and will lead to 14 day quarantines of staff and responders. No one plans to have an accident in the mountains. If you do, know that our response will be limited and will require the help of bystanders and other forest visitors. Furthermore, any accident will strain local first responders and hospitals. There are many ways to be outdoors and get needed exercise, backcountry skiing should not be among them now.
Yesterday, moisture lingered over the mountains keeping clouds in place for the day but produced no precipitation beyond the 1” that arrived before daylight. Temperatures stayed in the teens F with wind from the NW between 50 and 60 mph.
Today, high pressure will create a pleasant day in the mountains. Skies cleared overnight and should remain clear until the afternoon. Temperatures will warm through the day with the summits peaking in the upper 20sF late afternoon. Morning wind from the NW at 40mph will shift to the SW and decrease to under 20mph.
Tomorrow, the approaching warm front is bringing a good amount of moisture with it. Temperatures on the summits will start cold enough for snow but likely close in on the freezing mark mid-morning. An inch of liquid is forecast, with maybe 1-3” of snow before possibly mixing with rain. Wind will be from the SW, increasing from 20-30mph to 50mph.
Primary Avalanche Problem – Wind Slab
Small wind slabs formed from the inch of snow that arrived Thursday night. This snow fell on westerly wind around 50mph and should be easy to identify from a distance by it’s white color compared to the dirtier looking older snow. Up close, this will be the only snow that has not been affected by the sun until today heats up. These isolated pockets should be easy to manage. If skiing today, watch sluff management both with these small wind slabs and the older snow once the refrozen snow softens.
What is a Windslab Avalanche?
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
While our snowpack is generally stable, safe travel techniques can still have a good application today. When deciding where to ski, consider choosing your descent based on people as well as terrain. Many people may view getting into the backcountry today as a way to distance themselves, something that you may infringe upon by booting or skinning up right behind them. Giving people space can easily be done by choosing a line to ski that has fewer people. On top of that, it will also vastly increase your safety by cutting down on your overhead hazard. Please remember that others may have differing opinions about distance and travel choices and giving everyone some space in the outdoors is always a good thing.
The Sherburne and Gulf of Slides ski trails are snow covered to Pinkham Notch.
The Lion Head Winter Route remains the easiest route to the summit from Pinkham Notch but requires an ice axe, crampons (not just micro-spikes) and possibly a rope. This is a mountaineering route and requires solid skills for a safe, timely ascent.
Details on daily snowfall totals, precipitation type, total depth of snow and other information can be found on our page devoted to snow study plot data. Click here to check it out.
Recent snowpack and avalanche observations can be found here and on Instagram. Your observations help improve our forecast product. Please take a moment and submit a photo or two and a brief description of snow and avalanche information that you gather in the field.
Safe travel in avalanche terrain requires training and experience. This forecast is just one tool to help you make your own decisions in avalanche terrain. You control your own risk by choosing where, when, and how you travel.
Avalanche danger may change when actual weather differs from the higher summits forecast.
For more information contact the US Forest Service Snow Rangers, AMC visitor services staff at the Pinkham Notch Visitor Center, or the caretakers at Hermit Lake Shelters or seasonally at the Harvard Cabin (generally December 1 through March 31). The Mount Washington Ski Patrol is also available on spring weekends.
Posted 03/28/2020 at 7:00 AM.
USDA Forest Service
White Mountain National Forest