Avalanche Forecast for Saturday, February 9, 2019

This forecast was published 02/09/2019 at 7:08 AM.
A new forecast will be issued tomorrow.

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

A drop in temperature by nearly 50 degrees since yesterday is creating a hard, slick crust as our dominant snow surface. You may be able to find isolated and small pockets of wind slab from the trace of new snow overnight. That said, long sliding falls on our refrozen snow surface and brutally cold weather conditions should be of greater concern than avalanches today. Remember that the current unforgiving cold and wind quickly make small problems into big problems. All forecast areas have LOW avalanche danger.

The term Long Sliding Falls is mentioned in this forecast from time to time when a wet snow surface refreezes. The significance and danger of a small stumble on seemingly benign terrain cannot be overstated. If you have not practiced self arrest with an ice axe you should. If you have practiced, know that the effectiveness of this skill is limited in the hard icy snow you’ll encounter in the mountains this weekend. Self arrest is a last resort and may only serve to slow you down on your way to the floor of the ravine. In these conditions, very careful movement is necessary to prevent a fall from happening in the first place. Put crampons on before slopes steepen and get your ice axe out and ready before you expect to need it. Crampons and ice axes cause injuries almost as often as they prevent them, so never practice self arrest with crampons on or on a slope without a clean and flat runout.

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Danger Rating by Zone

Mountain Weather

The recent warm and wet weather quickly gave way to cold with extreme winds overnight. Temperatures are below or near to 0F throughout our terrain. The current summit temperature is -11F and forecast to drop a few more degrees before rebounding slowly to single digits below 0F tonight and tomorrow. A trace of snow fell last night and snow showers this morning could produce additional though minimal accumulation before our mostly cloudy skies trend towards mostly clear. Summit wind near 100 mph since early last night should shift from W to NW today while holding at just over 100 mph with stronger gusts. Wind speeds will decrease overnight towards 60 mph by tomorrow.

Snowpack and Avalanche Discussion

Our recently wetted snowpack is mostly refrozen and will continue to gain stability as the snow deeper in the snowpack refreezes. A crust on the surface is likely to be already supportable, especially in steep terrain, though may remain breakable in the trees or at low elevations. You may be able to find very small pockets of new wind slab, but by and large, our terrain is void of an avalanche problem. Today marks the formation of another crust that will become a factor in future snowpack stability. On the east side of the range, avalanche paths are well developed and now have a widespread smooth bed surface for future avalanches.

Additional Concerns

The Sherburne and Gulf of Slides ski trails are snow covered and firm to Pinkham Notch. Just in time for these low tide riding conditions, we’ve added a “Learn” tab to our website menu. Use these quality online avalanche education resources to prep for our next round of elevated avalanche danger.

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
05/22/19
05:25
Trace 6.2 MMTrace60 CM0.5 C2.0 C-1.0 CClearNo precipitationView
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

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
05/21/1934 F23 F .57 in 1.9 in73 MPH135 MPH

330 (NNW)

05/20/1951 F33 F 0.57 in 0.0 in48 MPH82 MPH

250 (WSW)

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)

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 02/09/2019 at 7:08 AM.

Ryan Matz, Snow Ranger
USDA Forest Service
White Mountain National Forest