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Tuolumne
Meadows Winter Conditions Updates
by Bruce & Tracey, 2003-04 Winter Rangers April
22, 2004 WEATHER:
(from April 15 to April 22) SKIING
CONDITIONS: The last week has been very cool and blustery. Westerly
winds have been blowing fresh snow around for days with a complete wind
direction swap to northeast winds on the 22nd (Thursday) blowing the
snow AVALANCHE/SNOW CONDITIONS: (above 8,000’) Avalanche danger is Considerable with a high potential for soft slab avalanches on leeward slopes above treeline. Slickrock areas with snow will have high avalanche potential during and just after thaw periods. DISCUSSION:
Cool temps and wind chilled the freeze/thaw cycle last week. The fresh
snow combined with the westerly wind has set up soft slab conditions
on leeward slopes and built soft cornices at the top of others. There
was also noticeable cross loading on other slopes. Most of this WILDLIFE:
The high winds and blowing snow drove even the ridgetop loving Rosy
Finches down to the Tuolumne area where we saw several large flocks
foraging on south facing road cuts which were snow free but still windy. WEATHER:
(from April 8 to April 15) SKIING
CONDITIONS: The spring snow is very dense and continues to be skiable
down to the last few inches. Some bare ground is showing on lower south
slopes and stream crossings are becoming a challenge but otherwise the
snow coverage is extensive. It is a good time to remember that our AVALANCHE/SNOW CONDITIONS: (above 8,000’) Avalanche danger is generally Moderate except where snow is present on granite domes and slickrock areas where the avalanche danger is High during and just after thaw cycles. DISCUSSION: Anywhere (all aspects) there is smooth rock we have seen thaw related avalanches, most of them slabs involving the entire snowpack depth. These will no doubt continue to slide until the rocks are snow free. The high density of the snow created by the March thaw has provided a lot of water to add to the snow weight and also helps lubricate the slick rock. With that combo don’t underestimate the small pieces of snow that are still clinging to areas like Olmsted Point or Polly Dome, they are equivalent to rocks in stature and will come down in a chunk or drip by drip. WILDLIFE:
The first Marmot tracks we’ve seen crossed the bridge near the
Tuolumne Lodge. Since then a few brown holes have appeared in the snow
in the high country indicating other Marmots coming out of hibernation.
Other WEATHER/SNOW:
(from April 1 to April 8) WEATHER/SNOW:
(from March 25 to April 1) SKIING CONDITIONS: Spring conditions prevail. A half foot of new snow on the 26th brightened the snow surface but otherwise is fast becoming corn snow, except for some pockets of remaining transitional snow (generally crusty) high on the north aspects. AVALANCHE/SNOW CONDITIONS: (above 8,000’) Avalanche danger is generally Low except where snow is present on granite domes and slickrock areas where the avalanche danger is High during and just after thaw cycles. DISCUSSION:
We have continued to see thaw cycle avalanches off slickrock and granite
dome areas. The melt/freeze cycle is the driving force throughout the
snowpack. Keep in mind that water is moving freely through WILDLIFE:
Not surprisingly we have started to see black bear prints, a good reminder
for backcountry travelers to tidy up their camps. If you’re viewing
this on the Yosemite website you’ll be able to check out the pine
“bone” photo. We’ve seen a lot of these green lodgepole
pine branch burls in which it appears that tree squirrels have methodically
removed all of WEATHER/SNOW:
(from March 18 to March 25) SKIING
CONDITIONS: Skiing along on sweet corn snow with butterflies flying
by, it must be springtime in the Sierra. Last week spring arrived both
metaphorically and by the calendar. The snow is still very firm and
corn snow can be found on most sunny exposures. Even the high north
exposures are ski friendly with a broken up dry crust or firm windpack.
Several AVALANCHE/SNOW
CONDITIONS: (above 8,000’) Avalanche danger is generally Low. Avalanche
danger is Moderate to High where snow is present on granite domes and
slickrock areas. Avalanche potential is highest during thaw cycles and DISCUSSION: In the last week avalanche activity has been mainly associated with granite domes and slick rock areas with the exception of a few rollies here and there and a cornice collapse we saw in the Rafferty Creek area (which just happened to overhang smooth granite). Skiers report seeing and hearing afternoon avalanches off Cloud’s Rest’s west face. There have also been at least two climax (to ground level) slides across the Tioga Road just north of Olmsted Point. The smooth granite will keep shedding its snow (and there is still plenty to shed) now that we have entered a strong freeze/thaw cycle. Remember the entire snowpack is hovering around the freezing point and may stay “thawed” well into the evening when the air temperature has dropped below freezing. WILDLIFE:
Every day is filled with birdsongs from new arrivals and those, like
Mountain Chickadees, which wintered here but are finding great occasion
for song. New arrivals include Red-winged Black birds, Robins, many
more Juncos, more than the usual one or two Stellar’s Jays and
Violet Green Swallows who seem to be on the same flight path as the
now more numerous Painted-Lady Butterflies. We think the Swallows fly
up from lower elevations for the day. We also saw our first chipmunk
since the one rogue sighting in January. A Bushy-tailed Wood Rat has
been seen the last couple mornings coming out from under the neighboring
cabin. We have not seen signs of our bushy tailed neighbor all winter
but spring seems to be bringing it out, perhaps in search of shiny treasures. WEATHER/SNOW:
(from March 11 to March 18) SKIING
CONDITIONS: The March thaw continues with most days reaching near 60
and night temps from mid teens to mid twenties. The snow is fast for
traveling except for the heat of the day when water tension (suction)
can slow down the fastest skis. An early starter can make some miles
while AVALANCHE/SNOW CONDITIONS: (above 8,000’) Avalanche danger is Low to Moderate. Avalanche potential is highest during thaw cycles particularly on domes and slickrock areas or areas of thin snow coverage (a couple feet or less) DISCUSSION: We have seen a few loose, wet avalanches. This prolonged warm spell has been settling the snow and we are fast approaching the melt/freeze cycle for avalanches. The other day we were surprised to find the snow temperature the same throughout the snowpack at 10,000’ on a NE aspect on Unicorn Peak. Except for the top 6” which fluctuate with the nighttime temps the snowpack was 31.8. This “Isothermal” condition will allow water to move much more freely through the snowpack. Although this settles the snow rapidly the snow cohesion is poor when temperatures are above freezing during the day increasing avalanche potential. Should the temperature stay above freezing overnight the possibility of a large avalanche is high. Fortunately the nights have been freezing but be cautious should you find yourself out during the seasons first warm nights. WILDLIFE:
March 14th the first Painted Lady Butterfly came low through the trees
heading west. The Clark’s Nutcrackers are still gathering in flocks
and being very vocal, sometime soon they become very secretive as they
go about the business of raising another brood. The other day while
we were skate skiing on the morning’s solid snow we saw a Great
Horned Owl soaking in the morning sun near the Ski Hut. We also saw
our first ground squirrel hole, which came up through 4 ½ feet
of snow out in Tuolumne Meadows. WEATHER/SNOW:
(from March 4 to March 11) SKIING
CONDITIONS: We have been hit by warm spring-like weather since Saturday
the 6th and the snow has been trying to catch up since. The snow has
settled more than a foot in the last week. Exposed areas are generally
firm or icy but can be very soft by midday. Watch for rotten spots around
trees or near rocks. There is not a proliferation of corn snow yet in
the high country but timing can provide some good spring-like conditions.
More protected slopes have thaw crust of varying thickness and some
windpack and AVALANCHE/SNOW CONDITIONS: (above 8,000’) Avalanche danger is Moderate. Avalanche potential will increase during thaw cycles particularly on domes and slickrock areas. DISCUSSION:
There was some thaw avalanche activity early in this present warm cycle
mostly on west or south facing slopes. We saw some areas of loose wet
slide activity in the Horse Creek drainage out of Twin Lakes. Otherwise
most activity was confined to rollies. We did see some slopes in WILDLIFE:
We recently mentioned that we wondered what the coyotes have been feeding
on these past weeks or even months. With the firm snow conditions we
have observed coyote tracks for many miles up drainages, over passes
and WEATHER/SNOW:
(from March 1 to March 4) SKIING
CONDITIONS: Snow is settling rapidly with temperatures rising above
40 degrees for the first time since early February and expected to rise
over the weekend. While the warmer temps may feel springy the snow will
have to go through the crust and mashed potato transition for a few
days. Right now there is still powder in the protected areas. A group of seasoned backcountry skiers from Mammoth Lakes that spent last week skiing the steeps near the hut told us about a website they maintain for local backcountry skiers it is www.SierraBackcountry.org; it is interactive and they hope to build on the information base over time. AVALANCHE/SNOW CONDITIONS: (above 8,000’) Avalanche danger is Moderate with caution advised on leeward slopes where loading has occurred. Avalanche potential will increase during thaw cycles particularly on dome and slickrock areas. DISCUSSION:
Our last storm on the 2nd put down a half foot of new snow with relatively
strong winds from the SW. More significantly though the following day
we had light snow with strong NE winds. Look for suspect wind slabs
and shaky cornices formed from this NE wind which had plenty of new WEATHER/SNOW:
(from Feb 24 to March 1) SKIING
CONDITIONS: Snow coverage is as good as it has been this winter since
we are at our deepest snow depth. We just completed snow course measurements
for March 1st, Tuolumne Meadows is just shy of 7 ft of snow (there is
always about 10 more inches of snow in the meadows than at our cabin).
The Snow Flat Course near the May Lake Trailhead was the deepest at
10 ½ ft. Powder conditions have prevailed with mid-calf or shallower
trailbreaking. Warming conditions predicted for later this week may
crust AVALANCHE/SNOW CONDITIONS: (above 8,000’) Avalanche danger is Considerable after being High over the last weekend. Expect increase in avalanche potential with additional snow or during a thaw cycle. DISCUSSION:
We have been focused on doing snow surveys the last few days and have
not done a significant amount of snow analysis on steeper aspects. We
have observed the remnants of several natural slide cycles since last
Wednesday the 25th. One slide blew through the trees on a north aspect
of The Lamb and deposited snow across the Tioga Road. What has caught
our attention most though is the absence of slides on some of the “ole
reliable” avalanche areas like Polly Dome, Tenaya Peak, and Olmsted
Point area. It’s not that these areas are without some avalanche
activity, we WILDLIFE:
Our first February without a Blackbird sighting although we heard that
at least one was seen in Yosemite Valley. The White-Breasted Nuthatches
that we are suddenly seeing here and there daily may have returned from
a short winter sabatical or just stayed out of our sight for months.
We still see occasional coyote tracks and always wonder what they find
to sustain themselves (the biggest critter around besides skiers) in
the deep snow. In past winters coyote scat seemed to consist almost
entirely of juniper berries. We have not noticed an abundance of juniper Returning
one evening through Tuolumne Meadows we noticed a pile of plucked feathers
in the middle of the meadow in the middle of the trail. The feathers
were that of a pine siskin or female crossbill judging from the yellow
feathers. It appeared as though a Northern Goshawk had killed the bird
then decided to pluck it out in the middle of the meadow. We figured
the hawk would probably not be bothered by all the bird’s friends
and relatives if it perched in the open rather than if it perched in
a tree where the smaller birds have the heckling advantage. Of course
the other PS: Thanks again to Tioga Pass Resort for picking up our mail and special thanks to the handful of skiers who have carried our mail from the Resort to Tuolumne. WEATHER/SNOW:
(from Feb 13 to Feb 24) SKIING
CONDITIONS: Wow, have we had great snow. Lots of new snow, which has
settled quickly but cool temperatures for a soft surface. It sounds
like we are in for a blast of snow Wednesday the 25th so we will try
to update again in a couple days. We experienced some technical difficulties
last AVALANCHE/SNOW
CONDITIONS: (above 8000’) Avalanche potential appears to be Moderate,
with considerable consequences should a human caused slab avalanche
occur in some areas. Most granite domes and slickrock areas are DISCUSSION: Last week we received two significant snow falls on the 16th and 18th with scattered snow showers other days. Both storms were relatively wet with the first storm producing slides on all aspects above and below treeline. The slides occurred on an old sun/wind crust. The second storm laid down over two feet of moderately heavy snow but without the wide spread slide action. A test pit on the 23rd around 10,000 ft, north aspect of Johnson Peak area showed several weak layers with clean shear surfaces down through the top three feet of the snow pack. One shear at 10” another around 24” and a disturbingly deep shear around 40”. This deep shear layer had small spherical crystals with flat (faceted) sides but very thin or nonexistent connection (necks) between crystals. A group of “regulars” staying at the ski hut have found similar results and have been cautious about hanging themselves out on the “big stuff”, like slopes where a small slide could trigger a deeper one. Wednesday’s (25th) predicted snow could produce slides in and of itself and could also add the load necessary to trigger some of the buried shear layers already present. WILDLIFE: Despite the stormy weather we usually see or hear our first Red-winged Blackbird this time of year. The snow is nearly as deep as it has been all winter and will probably go over the top this week. Perhaps we will have to wait a while longer for the first spring arrivals. I should mention that the first Red-winged Blackbird I saw last year was during a snow storm. WEATHER/SNOW:
(from Feb 6 to Feb 13) SKIING CONDITIONS: Strong north and east winds early in the week scoured meadows and left windpacked and windcrusted slopes above treeline. Cold temperatures have helped maintain powdery snow in protected areas and provided light snow for the wind to move around. Trail breaking has generally been boot top deep except for firm wind pack or cardboard like windcrust. AVALANCHE/SNOW CONDITIONS: (above 8,000’) Avalanche danger is generally Moderate. Stay alert for wind loaded slopes and newly created cornices. Any granite domes and slickrock areas have avalanche potential when snow covered. Expect increased avalanche danger if we get any significant warming. DISCUSSION: Snow banners waved all day long off peaks and ridges for several days early in the week. These strong north and east winds loaded many leeward slopes and double corniced many ridges such as Unicorn Peak.We have not seen any natural releases in the last week but evidence would have been quickly erased or just hard to pick out on the scoured snow surface. WILDLIFE:
We have been seeing large flocks (6 to15) of Clark’s Nutcrackers
in and around Tuolumne Meadows the last couple weeks. We noticed the
Nutcrackers becoming very gregarious about this time last year instead
of the usual 1 or 2 birds sighted the rest of the year. We were also
fortunate enough to see a Pine Marten as we sat down to breakfast, it
was well into its morning rounds as we were just preparing for ours.
The Marten appeared light on its feet in the powdery snow. WEATHER/SNOW:
(from Jan 30 to Feb 6) SKIING CONDITIONS: It was a lot like winter this last week. Fresh powder snow and cool temperatures. AVALANCHE/SNOW CONDITIONS: (above 8,000’) Avalanche danger still appears to be CONSIDERABLE on north or near north aspects. Any granite domes and slickrock areas have avalanche potential when snow covered. DISCUSSION: The north aspects of the Cathedral Range are full of slides, sloughs and surface cracks, left from the 1 to 2 feet of fresh snow we received early this week. Besides the larger slides off peaks like Unicorn, smaller slides too numerous to count, have come off short slopes and banks of 35 degrees or more. Even more numerous are the stress fractures or surface cracks found where terrain steepens or becomes convex. Most of this action was early to mid week but we still found several weak spots within the top 24” of the north aspect snowpack. We found shear layers within the new snow, most easily detected by holding a column of new snow on a shovel and tapping the shovel from below. We suspected its presence by the natural slides at that depth but many shear tests that work from the top of the snow down would not easily reveal this weakness. There was also a weak layer several feet down in the snow that appeared to be an old surface, possibly associated with buried surface hoar. In some areas we heard whumping of the snow surrounding our skis. We assume this was settling on recrystalized snow that left weak hollows under light crusts before this new snowfall. During this last storm we had winds from the south that built cornices and loaded many near north aspects, no doubt adding to the above mentioned slides. We have not had any significant warming since this last good storm so be alert for the first warm days on this new snow. WILDLIFE:
Last week we mentioned the Red Crossbills which we had seen for the
first time this winter. It has been very noticeable where these flocks
have been feeding by the cone litter and whole pinecones scattered under
various lodgepole pines. Although the Mountain Chickadees, Pine Siskins
and Cassin’s Finches have also been hitting the lodgepole smorgasbord,
they have left a cleaner plate. WEATHER/SNOW:
(from Jan 22 to Jan 29) SKIING CONDITIONS: A couple light snowfalls have refreshed the snow surface. The single digit lows and many cold days has also helped soften (recrystalized) the snow surface with only the south tilted slopes showing much suncrust. AVALANCHE/SNOW CONDITIONS: (above 8000’) Avalanche danger is generally Moderate but a High potential for avalanches exists on any steep slopes from the newly fallen snow. The few inches of newly fallen snow is weakly bonded to the previous snow surface. Steep slopes with longer runs are dangerous do to vertical accumulation of newly fallen snow. Any steep granite domes or slickrock should always be considered as potential avalanche terrain. DISCUSSION: We have seen many loose snow avalanches all involving the new six inches of snow we received earlier this week. These surface sloughs help illustrate the poor bond and/or the sliding surface present on or near the surface of the older snow. We did not have significant winds with either of the light snowfalls. Strong winds could easily move this new snow, loading lee slopes. Keep in mind the old ice surface and recrystalized snow which is still poorly bonded to this new snow especially as these weak layers get buried inch by inch or faster. Last weeks single digit nights and near freezing highs have continued recrystalizing snow near or on the surface. WILDLIFE:
We have recently seen a couple small flocks of Red Crossbills taking
advantage of the abundant lodgepole pinecone seeds. While their bill
is well adapted for removing seeds from stiff pinecones we have also
seen them pluck entire cones and fly to a perch with cone in bill. WEATHER/SNOW:
(from Jan 15 to Jan 22) SKIING
CONDITIONS: Ski conditions have changed very little over the week. Effects
of wind or sun have extended to all surfaces except for a few inches
of recrystalized snow on protected tree slopes. This quiet snow is punctuated
by icy areas directly under the trees. The settled snow has made AVALANCHE/SNOW CONDITIONS: (above 8,000’) Avalanche danger is generally Moderate to Low with the highest potential for avalanches on any steep granite domes or slickrock areas. DISCUSSION:
We have seen little evidence of natural releases this past week. The
most recent notable slides we have seen have been climax (to the ground)
slabs off granite. One slab went across the road just northeast of Olmstead
Point and several large wet slabs came down off Polly Dome. The most
recent avalanche news is occurring in and on the surface of the snowpack.
There are many firm surfaces around from windpack to melt/freeze ice
crust. These could be future sliding surfaces when buried. There has
also been wide spread recrystalization of surface and subsurface (just WILDLIFE: One calm sunny day on Tresidder Peak we heard the distinct clucking of a White-tailed Ptarmigan. Try as we might, we could not locate a black eye or beak that would give away the location of this otherwise white bird introduced to the Sierra a few decades ago. We were also surprised to see a chipmunk out and about near Snow Flat. Chipmunks do not accumulate fat for true hibernation like ground squirrels. They generally remain inactive during winter except for raids on their food stores, equivalent to a midnight raid on the refrigerator. The Chipmunk we saw was not moving at top summer speed and is probably fast asleep by now. PS: We
have been asked several times and the answer is: Yes! If you pass by
the Tioga Pass Resort, stop and check it out and ask if they have any
mail to deliver to Tuolumne. We often ask skiers to take our outgoing
mail out with them. WEATHER/SNOW:
(from Jan 8 to Jan 15) SKIING CONDITIONS: Sunny days and cool nights have left us with a variety of snow conditions. Strong SW winds late last week scoured some high exposed areas and left some moderately soft wind crust in others. Protected slopes (from wind and sun) have several inches of recrystalized snow from cool nights and overnight surface hoar formation. We have been enjoying this “fast powder” in the north facing trees. There is some sun crust on very sunny exposures. AVALANCHE/SNOW CONDITIONS: (above 8,000’) Avalanche potential is generally MODERATE with some pockets of higher instability due to wind loading. Any granite domes or slickrock areas should be considered HIGH avalanche potential when snow covered. DISCUSSION: In the past week we have seen evidence of a variety of avalanche types on all aspects: wet point release off south slopes, soft slab off a west facing granite dome, and loose snow slide caused by cornice failure on a NE slope. Not a significant amount of natural slides, just a wide range of conditions reflected in the avalanches we have seen. In our most recent stability tests we found several weaknesses at 6” and also 1 ½’ deep on near north aspects. Both seemed moderately unstable but vary from location to location. Friday the 9th we had strong SW winds all day moving a tremendous amount of snow. I would be wary of NE aspects that look loaded, they probably are. Here is a very interesting photo of an avalanche near Cathedral Peak.
WILDLIFE:
A week without new snow and a strong wind day has scattered the tiny
winged lodgepole pine seeds across the surface of the snow and allowed
us to see the tracks of those that feed upon the abundance, from Mountain
Chickadees who come down from the trees and mice who come up from under
the snow. Tuesday the13th was our lucky day when we spotted a Golden
Eagle soaring near Gaylor Ridge then it perched on a rock near the ridge
crest. It was an unusually calm day and the mature eagle was in no hurry
to leave, perhaps its eyes were following the multitude of Whitetail
Jackrabbit tracks in Dana Meadow. WEATHER/SNOW:
(from Dec 31 to Jan 8) SKIING
CONDITIONS: Just in the last few days trail breaking has become more
reasonable then epic, staying somewhere below the knees. The snow has
remained powdery but we seem to be out of the major storm series we
were in AVALANCHE/SNOW CONDITIONS: (above 8000’) Avalanche danger is still CONSIDERABLE on steep exposed slopes. DISCUSSION:
We have received just under 100” of new snow in the last two weeks.
Although settling has taken place it has been slow. While ski penetration
is not quite knee deep, boot penetration is crotch deep to the tallest
Tuolumne Winter Ranger. We found a common shear buried about 1 ½ WILDLIFE:
Last week we suggested “hunkering” as a good skier survival
method for travelers during snowstorms. We saw evidence that at least
one of the local birds, probably a Blue Grouse or bird that size judging
from its droppings, was doing just that during the New Years first snow
storm. WEATHER/SNOW:
(from Dec 24 to Dec 31) SKIING CONDITIONS: Snow city! A series of storms has left several feet of unconsolidated snow. Trailbreaking has been thigh deep or to just below the knee, depending on how many days since the last snowfall. Good timing will be necessary to navigate the storms predicted in the coming days. Its always worth having flexible enough plans to be able to “hunker” for a day or two until travel is possible and much safer. AVALANCHE/SNOW CONDITIONS: (above 8,000’) Avalanche danger is CONSIDERABLE and could easily return to HIGH with more new snow, warming temperatures or substantial winds. All steep granite dome areas remain HIGH for avalanche potential. DISCUSSION: Tuesday (12/30/03) was a high avalanche activity day. With several new feet of powder snow we saw many natural loose snow avalanches starting on overloaded slopes or from rock & tree sloughs. There was definitely more action on slopes that received some afternoon warming from the mostly veiled sun like Lembert dome. The shear amount of new unconsolidated snow has bumped the avalanche potential up. Some areas like the east flank of Cathedral Peak showed vast areas of rippled snow left from side slope winds. The settling rate and stabilization of snow is not staying up with the new snowfall at these cooler temperatures. There is also a great deal of fresh snow available for wind transport at these cooler temps. We are in a cycle of snow accumulation and increased avalanche potential. WILDLIFE:
We are still seeing Cassin’s Finches around and have had our fourth
Goshawk sighting in the Tuolumne area. We are always surprised to see
the Pine Marten tracks so prolific even in the fresh, deep powder. It
is also notable how accessible the lodgepole pine cones are (hanging
under the branches) even when every tree branch is loaded with snow. WEATHER/SNOW:
(from Dec 19 to Dec 24) SKIING CONDITIONS: Skiing has been a good balance between fresh snow and firm enough snow to allow headway while trailbreaking. Forecasters are calling for several storms in the next few days so the balance may tip. We have
been asked about our mail service and since it is directly tied to snow
conditions we will share it here. Things have changed since Snowshoe
Thompson carried the mail through the high Sierras, but not much. From
Tuolumne Meadows we ski nine miles east over Tioga Pass to the Tioga
Pass Resort (TPR) and back. We usually need to break a trail but enjoy
the parts of the broken trail on our return that have not blown back
in. This, though, is only a long day’s ski; the real heroics start
at TPR. Those of you that have traveled up or down Lee Vining Canyon
have some feel for its AVALANCHE/SNOW CONDITIONS: (above 8,000’) Avalanche potential will increase dramatically during and just after the new snowfall. Be cautious around steep windward slopes. DISCUSSION:
In general the snow has been settling well with some weaknesses showing
in the newer snow layers. Windward slopes vary widely in stability but
all show recently built features with lots of soft formations that could
collapse under stress. If we receive the new snow forecast over Two of
this season’s first avalanche fatalities were snowshoers. If you
travel in the snow (even in your car) it would behoove you to have some
level of avalanche knowledge. There are books and classes and a good
way WILDLIFE:
Last week on a mail run I heard, then saw, a Belted Kingfisher next
to Ellery Creek near the Tioga Pass Resort. Some of the TPR crew has
seen it more recently although the creek is freezing over in many spots.
We WEATHER/SNOW:
(from Dec 11 to Dec 18) SKIING CONDITIONS: We have been enjoying an abundance of maritime powder, which has gotten heavier the last few warm days. The snow level on the east side is near the gate at 7,000' a few miles from Lee Vining. AVALANCHE/SNOW CONDITIONS: (above 8,000') Avalanche potential is generally Moderate with higher potential on granite domes and steep rock slabs. DISCUSSION:
We noticed that a few small avalanches had occurred early in the week,
mostly involving last Sunday morning's new snowfall. Sunday's storm
had strong SW winds and several slides had started from wind-deposited
snow off of steep rocky starting zones. We have also seen evidence in
some steeper, rocky areas of other small slides, which appear Our snow
pit tests on Unicorn Peak, near last weeks test area, showed weaknesses
about 6" down (bottom of freshest snow) and another weakness several
feet down on top of the old November ice crust. Both a stuffblock test
(dropping a ten-pound bag on an isolated shovel size snow column) and WILDLIFE:
Flying Squirrels? Actually they are falling squirrels. After a new snowfall
we've noticed that Chickaree or Douglas Squirrels will jump from branches
(sometimes 10'-20' high) into the snow then swim their way through the
snow looking like wound up rubber band toys with much effort and little
forward motion. Then they will climb another tree and launch The falling
squirrel prints look similar to snowball impressions in the snow since
their landing is in a tight four-point stance. While working one winter
in Glacier National Park we would use a much more revealing impression
left by Pine Martens and Fishers when they leaped from a tree indicating
body length and width, even head and tail impressions in favorable conditions.
The dimensions would often help determine which WEATHER/SNOW:
(from Dec 5 to Dec 11) SKIING CONDITIONS: We received a very wet snow last weekend with a lighter snow on Tuesday night. The new snow coverage has opened up the ski possibilities while requiring trail breaking (knee deep on Wednesday) to fulfill those possibilities. AVALANCHE/SNOW CONDITIONS: (above 8000') The chances of a human-triggered avalanche are CONSIDERABLE. Particularly on steeper slopes above 9,500' where wind slabs have developed or a rotten snow base exists. DISCUSSION: The first 3" of soggy snow we received last weekend had a water content of over 1". This snow (at times rain below 9,500') has developed a thick crust 4-5" of varying hardness (elevation dependent). The next 10" of snow we received had a water content of just over 1". On Tuesday we received 12" of powder snow with a water content just over ½". It seems like a good progression of solid to fluff, except for that ever haunting and now buried faceted layer which developed in November. We also had strong south and west winds with both storms, producing some very deep wind deposits. The snow could still be seen blowing on the Unicorn saddle as the sun set Wednesday night. Here is
a snow profile from the lower slopes of Unicorn Peak which was taken
before the last light dump of snow: elevation 9,900', aspect NE snow
depth 28", ski penetration was 6", boot penetration was 12"-28"
(to the ground). There was 14" of new dense snow with a hardness
of three fingers WILDLIFE: It has been stormy, readily covering mammal tracks and bird voices. We did see the Scrub Jay again near our cabin, it will be the first time we have had such a winter resident in our four winters here. WEATHER/SNOW:
(from Nov 28 to Dec 5) SKIING CONDITIONS: We were very excited to get those 2" of snow last Tuesday since it had been over two weeks since we received any measurable snow. It sounds like all of that may change this weekend if the predicted snow arrives. What snow we have will provide a good base for any fresh fluff on the flats, but if we get enough snow to lure skiers to the steeper slopes, caution is advised since the base layer may be very weak (see discussion). AVALANCHE/SNOW CONDITIONS: (above 8000') Avalanche potential could rise dramatically in the next few days with the addition of new snow on older faceted snow and old wind packed snow. DISCUSSION:
We have had some warm temperatures the last week, enough to form a surface
melt crust even in the shade. The faceted (loose sugary) snow still
exists below the crust in most areas. The facetes provide little support
for the overlying snow and make a poor ground anchor for snow on a WILDLIFE:
We are still seeing good sized flocks of Cassin's Finches, we think
it has to do with the healthy crop of Lodgepole Pine cones, at least
that is where we've spotted them. WEATHER/SNOW:
(from Nov 20 to Nov 28) SKIING
CONDITIONS: You know that feeling when you open the fridge door and
although your appetite is expecting a surprise your eyes are not surprised
to see everything like it was last time you looked? Well, when we open
our front door we are not surprise to see things looking like they did AVALANCHE/SNOW
CONDITIONS: (above 8000') Avalanche potential exists where few slope
anchors occur such as grassy slopes or granite domes and slabs. Also
rock fall danger exists due to ice wedging (freeze/thaw cycle) in DISCUSSION:
While I eluded to the fact that the snow conditions have stayed the
same for weeks, most savy snow watchers know that such a statement is
far from the truth. With no major snow fall in weeks the snow depth
has changed little, but the individual flakes of snow have undergone
immense change. With a fairly steady ground temperature of freezing
(which does not change much through the winter) and an air temperature
which has been WILDLIFE:
Ours are not the only lingering tracks. It is very obvious which trees
the squirrels prefer or where the Pine Martens hunt. The individual
lodgepole pine seeds have been slowly collecting on the old snow surface.
We noticed some interesting curly-cue tracks left by Jays or Clark's WEATHER/SNOW:
(from Nov 13 to Nov 20) SKIING
CONDITIONS: While our snow depth has stayed steady for almost two weeks
the snowpack has been consolidating and providing a more solid base
with every snowfall. On sunny, south slopes that base has gotten very
thin but everywhere else the low angle sun has had little effect except
for some crusting of the surface. We still lack a generous enough base
to ski off road or trail without rock skis. On Wednesday the 19th we
skied past Tenaya Lake which showed no sign of freezing up yet. It usually
freezes AVALANCHE/SNOW
CONDITIONS: (above 8000') Avalanche potential exists where few slope
anchors occur such as grassy slopes or granite domes and slabs. Also
rock fall danger exists do to ice wedging (freeze/thaw cycle) in areas DISCUSSION: Warmer temperatures and a few more inches of snow have slowed the development of depth hoar in the shallow snowpack. We have noticed some ice forming on all but the most southerly facing rock slab and dome areas. Everything from icicles to large thin "veraglass" ice sheets. Some of these could get covered in the coming snow storm forcast for this weekend. Keep in mind the possibility of these ice sheets buried under the snow. We have also seen many rocks the size of car engines or larger wedged out of road cuts by expanding ice and then melting temps. WILDLIFE:
We saw bear tracks in the snow in the Tenaya/ Olmstead area wandering
along the road for several miles. A good reminder to bear-proof your
food even though there is snow on the ground. The bear scat we saw indicated
that the bear may have been raiding squirrel caches or finding WEATHER/SNOW:
(from October 31 to November 13) SKIING
CONDITIONS: Ever been to a Halloween Party were everyone came in the
same costume? Well, Halloween herewas
just like that, everyone was dressed like a ranger and was scurrying
around all day closing things up and AVALANCHE/SNOW CONDITIONS: (above 8000') Avalanche potential exists wherefew slope anchors occur such as grassy slopes or granite domes and slabs. DISCUSSION:
The snow is still thin on many of the steeper slopes but don'tbe caught
in that "its too early for a slide" mode. Many terrain anchors,like
trees and rocks that stick out on the slopes, are still visible. If
a slope looks smooth and skiable in this early season it would be good
to know what type of ground and/or vegetation lies beneath. Already
a wide variety of snow conditions exist which will determine stability
for the coming weeks of winter. We have had a relatively thin snow pack
in the Tuolumne area with cold temperatures (many single digit lows
and just above freezing highs), while just a few miles to the west the
snow pack is WILDLIFE:
It is incredible how we spot deer every day until the road-closing storm
and then there are no deer or at least no tracks. We did find the remains
of a Mallard that had been eaten/plucked on the meadow's edge possibly
by a resident Goshawk or even the Falcon I glimpsed several weeks ago
by Lembert Dome. Whoever it was perched in a large tree on the Bruce &
Tracey,
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