Avalanche Forecast for Monday, February 11, 2019

This forecast was published 02/11/2019 at 6:57 AM.
A new forecast will be issued tomorrow.

NOT THE CURRENT FORECAST

This is an archived avalanche forecast and expired on 02/11/2019 at midnight.


The Bottom Line

Hard refrozen snow that dominates our terrain continues to present long sliding falls as a greater hazard than avalanches. If you do find soft snow without a crust in the alpine, you will have found a pocket of the very small and isolated wind slab that is our only avalanche concern. All forecast areas have LOW avalanche danger. Long sliding fall potential on our very hard and slick snow surface should guide your terrain choices today. Crampons, ice axe, and your ability to not fall are a must for travel on steep snow in the current conditions.

2019-2-11_printable_pdf

Forecast Area

Mountain Weather

Weather since the refreeze late Friday has done little to affect our snowpack. Summit temperatures hovered in the single digits below 0F yesterday, with our snow plots recording a high around 7F. High temperature on the summit should be just over 0F today. Wind from the WNW held in the 50-70 mph range and should remain at similar speeds while shifting NW through daylight hours. Summit fog for most of yesterday has cleared and skies should remain clear through the day. Tomorrow is forecast to be 10 degrees warmer with summit wind under 30 mph. An incoming storm will bring increasing cloud cover and significant snowfall late tomorrow into Wednesday.

Snowpack and Avalanche Discussion

Our surface snow is solidly refrozen and supportable in the alpine, with both breakable and supportable crust existing in the trees. Quite small and isolated wind slabs formed over the weekend may exist in our terrain; if you can find them, these are the only stability concern at this time. Most terrain is scoured to the robust melt/freeze crust. This crust is smooth and hard, presenting long sliding falls as our current key hazard. It is also likely to provide an ideal bed surface for slabs building Tuesday night into Wednesday. Avalanche paths are well developed on the east side of the range. Relatively smaller developed avalanche paths with significant terrain traps and nasty runouts can be found on the west side and at lower elevations. Keep these path development factors and the widespread smooth crust as a bed surface in mind for size and consequence of potential avalanches as significant snowfall arrives tomorrow night.

Snow Plot Information

DateHN24HN24W
(SWE)
Density (%)HSTTotalAir TT MaxT MinSkyPrecipComments
11/20/19
06:18
3 CM 9.4 MM 21%3CM19 CM-2.5 C1.5 C-2.5 COvercastNo precipitation
11/19/19
06:15
0 CM 5.9 MM0CM17 CM1.0 C2.0 C-10.0 COvercastRain
11/18/19
06:20
0 CM 0 MM0CM21 CM-6.0 C-4.5 C-11.5 CBrokenNo precipitation
11/17/19
06:20
0 CM 0 MM0CM23 CM-11.5 C-9.0 C-14.0 CClearNo precipitation
11/16/19
07:00
3 CM 2.3 MM 11%3CM23 CM-13.5 C-5.0 C-14.0 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
05/30/1946 F36 F 0 in 0 in27.9 MPH55 MPH

290 (WNW)

05/29/1947 F33 F 0 in 0 in20 MPH48 MPH

290 (WNW)

05/28/1934 F28 F .71 in 3.7 in20 MPH48 MPH

290 (WNW)

05/27/1940 F27 FTrace 0 in38.9 MPH68 MPH

300 (WNW)

05/26/1948 F39 F .77 in 0 in48.7 MPH75 MPH

290 (WNW)

05/25/1947 F31 F .42 in 0 in17.7 MPH63 MPH

240 (WSW)

05/24/1942 F32 F .66 in 0 in44.8 MPH105 MPH

05/23/1944 F30 F .16 in 0 in26.8 MPH71 MPH

270 (W)

05/22/1934 F21 F 0 in 0 in36.2 MPH115 MPH

330 (NNW)

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)

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 02/11/2019 at 6:57 AM.

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