General Bulletin for Tuesday, December 24, 2019

This information was published 12/24/2019 at 2:46 PM.
A new bulletin will be issued when conditions warrant.

The Bottom Line

It has been 5 days since the last measurable snow and the snowpack is generally stable. The exception to this would include unsupported wind slabs found on steep terrain where triggering even a small avalanche could result in a slide-for-life above rocks and cliffs. Identify these wind slabs by looking for convex pillows of snow drifted into wind protected areas. Minimize your exposure to this hazard by traveling on low angle terrain, or snow supported by the surrounding terrain: concave or planar slopes. Travel one at a time and be extra cautious with crampons or ski turns continually considering the consequences of a fall. Fair weather is expected for the next few days. Enjoy the holidays and be safe.

2019-12-24 General Bulletin printable

Danger Rating

12/22 Tuckerman Ravine

General Bulletins are issued when unstable snow may exist within our forecast areas but before conditions warrant or available resources allow 5-scale avalanche forecasts. Thank-you to everyone who has submitted observations! We will start 5-scale forecasts on Wednesday, January 15 or earlier, if possible. Please remember that avalanches can and do occur before 5-scale avalanche forecasts are issued.

The summer Lion Head Trail remains the safer choice for accessing the summit of Mount Washington from the east.

The Tuckerman Ravine and Huntington Ravine trails are challenging climbs with significant avalanche hazard during winter. An ice axe and crampons are needed near treeline and above. The Winter Lion Head Route still needs more snow. The Sherburne ski trail has snow coverage to the parking lot though rocks and the occasional open water bar should be easy to avoid.

Mountain Weather

Temperatures in the 20s the next few days will continue to increase stability in the snowpack and no additional snow is expected until Friday when an approaching low may bring snow showers with low snow totals expected. Skies will be clear or partly cloudy with moderate winds at least until Thursday.  The longer range forecast suggests the potential for a larger storm and increasing avalanche hazard on Sunday & Monday. Be sure to check the Higher Summits forecast when making plans.

You can keep tabs on daily details of snow on the ground and 24 weather at our snowplots at the bottom of the forecast page of this website along with the weather resources, including a daily F6 report, produced by the Mount Washington Observatory on the summit.

Forecast Discussion

The Presidential Range has not had any significant precipitation since the 19th and none is expected until Friday. Surface conditions consist of wind slabs formed from 22cm of snow that fell the middle of last week, and to a lesser extent December 15 refrozen rain crust. Observations in the alpine report more widespread rain crust, though a surprising amount of  snow remains available for wind transport on the SE snowfields above Tuckerman Ravine.

Video taken Dec 22, a full 5 days after the last recorded snowfall. Small amounts of snow actively transported from the fetch of the Alpine Garden into the lee of Tuckerman Ravine.

Additional Information

Overall, our terrain remains poorly filled in with exposed early season hazards.

  • Rocks, trees and bushes lurk in the snow and in the fall line. Skiing or sliding into obstacles can ruin your day or worse. New snow may just barely cover a season ending stump or boulder.
  • Terrain traps and cliffs make burial and significant injury a real possibility, heightening the consequences of a fall or small avalanche.
  • Long sliding falls are a threat despite the appearance of new, soft snow on your approach. Wind can easily scour parts of your climb or hike down to a hard bed surface. What you thought would be a mellow snow climb can turn into something much more exciting. Don’t count on self-arrest to save you. Consider using a rope in third class terrain or sooner than normal due to the slick surface.

Snow Plot Information

Density (%)HSTTotalAir TT MaxT MinSkyPrecipComments
0 CM 0.1 MM0CM206 CM-3.5 C7.5 C-7.0 COvercastRain
Trace 1.8 MMTrace216 CM-7.0 C-4.0 C-7.0 CFewNo precipitation
14 CM 23.1 MM 14%62CM222 CM-8.0 C-6.0 C-8.0 COvercastNo precipitation
53 CM 49.5 MM 12%NC200 CM-6.0 C-2.0 C-6.5 COvercastSnowView
0 CM 0.0 MM0CM158 CM-1.0 C8.0 C-4.5 CClearNo precipitation

Avalanche Log and Summit Weather

Thank you Mount Washington Observatory for providing daily weather data from the summit of Mount Washington.

DateMax TempMin TempTotal (SWE)24H Snow & IceWind AvgWind Fastest MileFastest Mile DirAvalanche Activity
05/25/2054 F46 F 0.0 in 0.0 in18.7 MPH44 MPH

260 (W)

05/24/2054 F40 F 8.3 in 21 in8.3 MPH21 MPH

280 (W)

05/23/2055 F43 F 0.0 in 0.0 in15 MPH45 MPH

300 (WNW)

05/22/2055 F40 F 0.0 in 0.0 in37.4 MPH67 MPH

290 (WNW)

05/21/2053 F38 F 0.0 in 0.0 in29.4 MPH59 MPH

280 (W)

05/20/2050 F34 F 0.0 in 0.0 in29.4 MPH59 MPH

280 (W)

05/19/2041 F27 F 0.0 in 0.0 in15.3 MPH36 MPH

100 (E)

05/19/2050 F34 F 0.0 in 0.0 in11.4 MPH25 MPH

30 (NNE)

05/18/2045 F30 F 0.0 in 0.0 in14.7 MPH36 MPH

70 (ENE)

05/17/2040 F30 F 0.0 in 0.0 in17 MPH35 MPH

270 (W)

05/16/2037 F28 F .16 in 0.0 in38.8 MPH101 MPH

310 (NW)

05/15/2042 F32 F .95 inTrace 31.5 MPH95 MPH

250 (WSW)

Please Remember:

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 12/24/2019 at 2:46 PM.

Jeff Fongemie, Snow Ranger
USDA Forest Service
White Mountain National Forest