General Bulletin issued on Tuesday, May 14, 2019

This forecast was published 05/14/2019 at 7:02 AM.
A new bulletin will be issued when conditions warrant.

The Mount Washington Avalanche Center will no longer issue daily avalanche forecasts for the 2018/19 season. Read more

The Mount Washington Avalanche Center will no longer issue daily avalanche forecasts for the 2018/19 season. Instead, we will post an updated General Bulletin as needed, in case of significant snow or weather events that might vary from the typical daily changes that come with spring weather. We will also keep you informed about the official closure of the portion of the Tuckerman Ravine Trail from Lunch Rocks through the Lip and Headwall as well as the switch from the Lion Head Winter Route to the summer trail. Observations from the field will continue to be a valuable resource, so please keep submitting photos, videos and observations here and we will do the same. Check the Forecast page for update on Sherburne Trail closures, which are imminent as spring snowmelt continues.

The switch to a General Bulletin does NOT mean that the mountains are now a safe place to ski. The hazards which emerge in the spring are significant and require careful assessment and strategic management. If you have never skied Tuckerman, peruse our Incidents and Accidents page for spring related incidents involving avalanches, long sliding falls, icefall, crevasse and moat falls, and other incidents related to diurnal changes in the snowpack. These will help you understand and plan for these hazards.


The Bottom Line

Avalanches will become possible as late season snow accumulates in our well developed slide paths on Tuesday. Small and relatively harmless loose avalanche types are likely to occur in the steepest terrain but thicker storm slabs could be triggered on larger slopes and in steep gullies if the upper end of the forecast 6-12” of snow falls, particularly if the snow is further loaded into wind slabs. Be on the lookout for these wind slabs to develop as wind speed increases on Wednesday. Wind slab size should be limited by the lack of snow available in the currently melted out alpine zone but could still be large enough to carry you and possibly bury you. Also, the new snow may be subjected to rapid warming as skies begin to clear Wednesday which could make wet snow avalanches increasingly possible.

Danger Rating by Zone

Bear in mind that any avalanche activity this week will be particularly dangerous due to the state of the snowpack. Rocks, holes, slots and trees have all reemerged over the past few weeks of melting and will serve as terrain traps and obstacles to strike in a sliding fall on the old, refrozen snow beneath the new. Evaluate the snow and terrain carefully and employ standard safe travel techniques such as moving one at a time on steep slopes, carrying probe and shovel and wearing an avalanche beacon. If you do not have any of those things, wait until this new snow and wind slabs have settled, hopefully by the weekend.

2019-5-14 General Bulletin

Mountain Weather

A storm in the Gulf of Maine is bringing new snow to elevations above 2000 feet with 10cm (4”) of new snow recorded on Monday night at Hermit Lake (3,800’). Initially, winds are forecast to remain in the 20-35 mph range from the east before shifting north and increasing in speed on Tuesday afternoon. By Wednesday, winds will be from the northwest at 30-45 mph with higher gusts. Temperatures on Tuesday will hover in the high 20’s at Ravine elevations during the snowfall. Anticipate temperatures pushing above freezing later in the week though continued unsettled weather may bring more light snow and rain at Ravine elevations.

Snowpack and Avalanche Discussion

Snowfall totals from this storm will vary widely by elevation and aspect within the Presidential range but certainly enough snow will fall to restore concerns about avalanches, adding complexity and challenges to skiing or hiking. Prolonged periods of melt have opened deep cracks in Tuckerman Ravine and holes have grown elsewhere in the snowpack near rocks and over streams in steep gullies. New snow will obscure these hazards from view. Keep the following hazards in mind as you make terrain decisions in our dynamic spring backcountry conditions:

Steep snow and ice in gullies and trails, such as the Lion Head Winter Route, become very hard during any frozen periods in our spring melt/freeze cycles requiring crampons and an ice axe to climb with security. The tops of many ski descents also fit this description.

Additional Concerns

Due to heavy snow and wind loading this winter, the Lion Head Winter Route remains the preferred, easier route to the summit from the east side. The new snow on the Lion Head Summer Trail makes this option particularly poor. The Sherburne and Gulf of Slides ski trails have little snow cover below Hermit Lake. Expect ice, open stream crossings, rocks, bare patches and plenty of mud all barely concealed by new snow. If you attempt to ski further than the rope set to direct ski traffic to the Tuckerman Ravine Trail, be conscientious of erosion damage caused by walking on soft ground by moving over to the Tuckerman Ravine trail using one of the crossovers when needed. Please remove your skis and walk down the Tuckerman Ravine Trail to avoid collision with the many hikers on the trail.

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.

The young man who was last seen heading up the Winter Lion Head Route on March 8 remains missing.  It is thought that he may have been intent on taking his own life. If that is the case, his remains may be somewhere with the Cutler River Drainage,  around the summit or within a few hours hike on the steep part of Lion Head Winter Route. Please report any potential clues to the NH Fish and Game officers at 603-271-3361 or to USFS Snow Rangers at mwactucks@gmail.com or via AMC Front Desk staff at Pinkham Notch Visitor Center. If it is clear that you have found him, please call 911.

Avalanche Safety Information Study

Please contribute to the effort to improve backcountry avalanche forecasts! Researchers in Canada devised a study to better understand how we communicate the avalanche risk, and we need your help. Please fill out this survey. It will take a few minutes, but it will help us as we work on new ways to give you the most important avalanche information.

Snow Plot Information

DateHN24HN24W
(SWE)
Density (%)HSTTotalAir TT MaxT MinSkyPrecipComments
05/21/19
05:25
0 CM 4.2 MM0CM60 CM2.0 C15.0 C2.0 COvercastNo precipitation
05/20/19
05:30
0 CM 20.4 MM0CM68 CM11.0 C12.0 C3.5 CObscuredNo precipitation
05/19/19
05:25
0 CM 0.0 MM0CM72 CM4.0 C6.0 C2.0 COvercastNo precipitation
05/18/19
05:20
0 CM 7.6 MM0CM80 CM1.0 C6.0 C1.0 COvercastNo precipitation
05/17/19
05:25
0 CM 0.8 MM0CM84 CM4.0 C10.0 C0.0 CClearNo precipitation

Avalanche Log and Summit Weather

Daily Observations


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
05/19/1951 F34 F .6 in 0 in34.2 MPH66 MPH

250 (WSW)

05/18/1934 F26 F 0.06 in 0.5 in39 MPH74 MPH

300 (WNW)

05/17/1940 F28 F .22 in .05 in37 MPH81 MPH

300 (WNW)

05/16/1932 F25 F .03 in 04 in22.8 MPH40 MPH

310 (NW)

05/15/1926 F20 F .05 in .4 in32.1 MPH67 MPH

330 (NNW)

05/14/1928 F17 F .2 in 2 in19.1 MPH57 MPH

100 (E)

05/13/1928 F19 F .07 in 0.9 in34.6 MPH67 MPH

100 (E)

05/12/1931 F17 F 0 in 0 in20.5 MPH47 MPH

330 (NNW)

05/11/1932 F18 F .1 in 0 in53.6 MPH84 MPH

300 (WNW)

05/10/1944 F27 F .85 in 0 in50.1 MPH88 MPH

220 (SW)

05/09/1942 F20 F .04 in 0 in18.6 MPH44 MPH

190 (S)

05/08/1927 F18 F 0 in 0 in38.3 MPH65 MPH

330 (NNW)

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 05/14/2019 at 7:02 AM.

Frank Carus, Snow Ranger
USDA Forest Service
White Mountain National Forest