Avalanche Forecast for Monday, April 6, 2020

This information was published 04/06/2020 at 6:25 AM.
A new forecast will be issued tomorrow.

NOT THE CURRENT FORECAST

This is an archived avalanche forecast and expired on 04/06/2020 at midnight.


The Bottom Line

Solar gain and above freezing air temperatures at mid elevations will be the driving factors for loose wet avalanches today. The danger level is rated as MODERATE. Be mindful of areas that may acquire solar gain faster than others: rock buttresses, exposed rocks and south facing slopes. Indicators of wet snow instabilities appear in the form of roller balls, rapidly warming temperatures and melting snow. In addition to avalanche hazards now is the time of year that crevasses are opening up and creek crossings are undermined by flowing water. Conditions under foot can change rapidly in the spring.


Mountain Weather

Yesterday intermittent clouds allowed for strong solar gain at times throughout the day. Ambient air temperatures topped out at 32F at the summit at noon.  W wind increased from single digits to 38 mph. Precipitation started in the evening with mixed precip continuing during the overnight hours 0.7” of new snow was recorded at the summit.

Today  A cloudy morning will pass making way for clear skies the rest of the day. Temperatures will be in the low 20sF at the summit and 50-60mph wind will be present from the W.  Solar gain, and warm ambient air temperatures will  have a strong influence on today’s travel plans.

Tomorrow Mostly cloudy skies will persist for most of the day, Summit temps will be in the low 20sF and a NW wind will vary in speed between 35-50mph.

Primary Avalanche Problem – Wet Loose

Wet Loose

Aspect/Elevation

Likelihood

Size

Warm ambient temperatures and Solar gain today will weaken bonds in our snowpack. Surface instability will be present on steep slopes. Any new snow that did accumulate at higher elevations likely did not bond well to the old surface and will further create instability. Sluff management will be the key. A loose wet avalanche is more likely to carry you into unwanted terrain than bury you.

  Wet Loose avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.

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
05/25/2054 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 04/06/2020 at 6:25 AM.

Joe Soccio
USDA Forest Service
White Mountain National Forest