Snowpack and Avalanche Information for Friday, May 08, 2020

This information was published 05/08/2020 at 7:34 AM.
A new bulletin will be issued when conditions warrant.


The Bottom Line

Winter conditions have returned once again with summit temperatures dipping into the single digits with 4-8” of new snow Friday night and Saturday. Our existing snowpack is mostly isothermal and icy on the surface at mid and upper elevations and will remain that way into next week. Expect new wind slabs to develop Saturday as very strong northwest winds load east facing terrain. The new snow and loading on an icy, smooth bed surface will create the potential for natural releases, particularly on slopes and gullies downwind of a large fetch. Wind speeds will approach 100 mph from the northwest on Sunday resulting in a mix of scoured terrain, hard wind slabs and more natural avalanches in lee terrain. Temperatures will warm early next week and rise above freezing at middle elevations and below as skies clear creating the possibility of wet snow avalanches in sunny locations.

Danger Rating

Mountain Hazards

Despite the date on the calendar, new snowfall and winter conditions have returned to higher elevations in the Presidential Range. A cold front followed by a coastal storm will bring upslope snowfall, cold temperatures and high winds to the alpine. Plan accordingly for these changes by reading the weather forecast before you head out (MWObs Higher Summits and NWS Hourly forecast).

One tool to help reduce the chance for unwelcome surprises is the hourly weather information produced by MWObs summit staff. The NWS displays the hourly data going back 7 days here.

Forecast Discussion

Recent snowfall earlier this week was underwhelming and did not do much more than create some thin pockets of new snow over a hard surface. Some recreational ski traffic is finding a mix of hard, edgeable surface up high with softening snow at middle elevations. Travel conditions in a single day could vary from the need for floatation in rotten lower elevation snow to crampons and ice axes on hard névé. 

Overall, there’s still lots of snow at mid and upper elevations with few of the typical spring crevasse, moat and icefall hazards yet to emerge. This means there are expansive and connected slopes which could produce large avalanches if the upper reaches of snowfall totals pans out. Don’t put away your beacon just yet!

 Keep the following spring mountain hazards in mind as you make terrain decisions:

Additional Information

The Sherburne and Gulf of Slides ski trails are no longer entirely snow covered to Pinkham Notch with water bogs rocks and dirt below around 3,000′. That said, a rescue litter will slide easily all the way to the parking lot with 4-5 rescuers.

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.

Snow Plot Information

DateHN24HN24W
(SWE)
Density (%)HSTTotalAir TT MaxT MinSkyPrecipComments
04/13/20
06:15
0 CM 0.1 MM0CM206 CM-3.5 C7.5 C-7.0 COvercastRain
04/12/20
06:20
Trace 1.8 MMTrace216 CM-7.0 C-4.0 C-7.0 CFewNo precipitation
04/11/20
06:20
14 CM 23.1 MM 14%62CM222 CM-8.0 C-6.0 C-8.0 COvercastNo precipitation
04/10/20
06:30
53 CM 49.5 MM 12%NC200 CM-6.0 C-2.0 C-6.5 COvercastSnowView
04/09/20
06:25
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
05/21/2053 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)

05/14/2035 F19 FTrace 0.1 in42.8 MPH85 MPH

300 (WNW)

05/13/2022 F9 F 0.0 in 0.0 in66.3 MPH98 MPH

300 (WNW)

05/12/2018 F12 F .51 in 3.5 in58.5 MPH100 MPH

310 (NW)

05/11/2034 F18 F .65 in 5.1 in35.1 MPH73 MPH

280 (W)

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 05/08/2020 at 7:34 AM.

Frank Carus
USDA Forest Service
White Mountain National Forest