| Good morning, this is Sue Burak with the Inyo National Forest Eastern Sierra Avalanche Center with the last advisory of the season.
Letters of support for the avalanche advisory service are welcome! Please send your comments and suggestions to sburak@psln.com or sburak@fs.fed.us.
MOUNTAIN WEATHER
Spring has finally arrived in the high Sierra. Highs today at the 8,000 to 9,000 ft elevations will be in the low 50’s. Higher elevations will be in the upper 40’s and breezy northwest winds around 30 mph will continue through the weekend. Night time lows will be right around freezing, 32F at most elevations with the exception of the higher terrain above 11,500 ft.
The temperature trend is for gradual warming through Sunday with daytime highs possibly reaching 70 F in the mountains.
SNOWPACK AND AVALANCHE DISCUSSION
Recent large wet snow avalanches on Mammoth Mountain and steep northeast facing terrain in the Tioga Pass area is the obvious, in your face clue that avalanches big enough to ruin your day are still possible. Snowline is moving up to about the 10,000 ft elevation an dif you are willing to hike and begin the descent before noon, steep terrain has good skiing conditions until treeline. Bottomless snow is always a possibility in areas where the snowpack is shallow and the old depth hoar from December and January still remains.
Despite balmy nighttime temperatures in the mid 30’s, the snowpack still freezes because the snow loses energy to clear skies. However, the freeze is not as deep compared to the hard freeze when temperatures are in the low to mid 20’s. Pay close attention to how deep the overnight freezes penetrate the snowpack. The gradual warmup this weekend could lead to increased avalanche danger.
Signs of an increased risk of wet snow avalanches are extensive snowballing, mushy snow and point release avalanches Avoid steep slopes, big bowls, cornices in the afternoon when sun angle is the highest.
Safe travel practices should be followed. Expose one person on a slope at a time, closely watch each other, carry avalanche beacons, probes and shovels and be well practiced with them.
BOTTOM LINE
The avalanche danger rating in spring conditions is LOW in the morning, increasing to MODERATE in localized areas in the afternoon. It still is possible to trigger a wet slide in the afternoon. This danger rating applies to the Rock Creek north to Tioga Pass. This is the last avalanche advisory for the season.
Please note that the avalanche danger rating in this advisory expires in 24 hours. This advisory is our best interpretation of snow pack conditions and NWS forecasts issued today. Backcountry travelers should be aware that elevation and geographic distinctions are approximate and that a transition zone exists between upper and lower elevations.
Avalanches do not happen by accident and most human involvement is a matter of choice not chance. Most avalanche accidents are caused by slab avalanches that are triggered by the victim of member of the victim's party. Even small slides can be dangerous. Always practice route finding skills and carry avalanche rescue gear. Remember that avalanche danger ratings are only general guidelines. Distinctions between geographic areas, elevations, slope aspects and slope angles should be made.
| This
month's advisories are brought to you by... |
|
Sponsor a month's worth of advisories and get your logo and tagline here.
Click here for more information. |
|
