Snow and Avalanches in Utah
Annual Report 1999-2000
Forest Service
Utah Avalanche Center
In partnership with:
Friends of the Utah Avalanche Center
National Weather Service
Utah Division of Comprehensive Emergency Management
Salt Lake County
Utah State University
Utah State Parks and Recreation
Copies of this report can be obtained by writing or calling:
Forest Service Utah Avalanche Center
2242 W. North Temple
Salt Lake City, UT 84116
(801) 524-5304 ph.
(801) 524-4030 fax.
Or view online at:
The Forest Service Utah Avalanche Center -- An Overview
Our goal:
Help keep people on top of the Greatest Snow on Earth instead of buried beneath it.
Where do avalanche accidents occur?
Ninety nine percent of all avalanche fatalities occur in the backcountry—areas outside of ski area boundaries where no avalanche control is done. Ski areas and highway avalanche control crews routinely knock down avalanches with explosives before the public arrives each morning. They have done their jobs so well that since 1980, less than one percent of avalanche fatalities have involved general public on open runs at ski areas or on open highways.
What kind of people get caught in avalanches?
Ninety two percent of people
killed in avalanches since 1985 have been recreationists, and they are almost
always very skilled in their sport. In
almost all cases their skill in their sport significantly outpaces their
avalanche skills. Looking at the most
recent 5 years of national data, nearly twice as many snowmobilers have been
killed as any other user group, followed by climbers, backcountry skiers,
snowboarders and miscellaneous recreationists such as hikers and snowshoers
(see charts on page 21).
How do people get caught?
In over 95 percent of
avalanche fatalities, the avalanche was triggered by the victim or someone in
the victim’s party. As Pogo says, “We
have met the enemy and it is us.” Which
is actually good, because it means that, 95 percent of the time, we can avoid
avalanche accidents through our route finding and snow stability decisions.
In summary, avalanche
fatalities occur almost exclusively in the backcountry, almost always involve
recreationists, and almost all avalanche incidents can be avoided if we choose.
How we help solve the problem:
We give backcountry travelers
the weapon of knowledge. In order to
avoid triggering avalanches, backcountry travelers need:
Critical, up-to-date avalanche information.
We issue daily, recorded
avalanche advisories that give the public important avalanche information they
need to make their life-and-death decisions in avalanche terrain. And we also forecast snow stability and
weather trends into the future. Our information
helps the public to decide what kind of terrain is safe, what kind is dangerous
and we give them useful clues to look for when they venture into avalanche
terrain.
We provide information on
current avalanche conditions primarily through our avalanche advisories. People access these by:
w Recorded
telephone message updated each day
w Live
interviews each day on two different public radio stations
w The
Internet
w Faxes
sent out each morning to businesses and Forest Service offices
w In
times of extreme or unusual avalanche conditions, we issue an avalanche warning
that reaches all the broadcast and print media as well as NOAA weather radio.
Finally, we “preach the
avalanche gospel” as much as possible to the local, national and international
media. This season, for instance,
several documentaries played on national television including National
Geographic and several on the Discovery Channel and PBS. UAFC staff are featured in most of these
documentaries.
Avalanche education:
We teach about 25 free, basic
avalanche awareness classes each season.
These not only give the public an overview of the avalanche problem, but
also some basic avalanche skills. These
classes encourage them to take a more involved avalanche class offered by the
private sector.
Our Philosophy:
Just because people hear the
information doesn’t mean they listen.
Even good information, if presented in a boring way, wastes the
taxpayer’s money because no one will remember it. Therefore, we try to make the
advisories entertaining so that people will remember what they hear and enjoy
the experience enough to use the advisories regularly. We try and use all the standard tools of
effective writing and speaking such as using active voice, first person,
examples and stories to illustrate points, humor where appropriate and reading
the bulletins in a natural voice, like talking to a friend. The recorded bulletins are informal, chatty
and funny, yet informative. It also
makes our work fun.
We believe local forecasters do a much better job than distant forecasters.
Local people know local
conditions better. They can get out in
the mountains every day, they see it from their window and they talk with
people on the street about it. Because
of this, we believe that local people should issue avalanche bulletins for
local areas, as long as they have the avalanche skills to do so. For this reason, four crews of avalanche
forecasters operate in Utah, one in Logan, another in Salt Lake City, one on
the Manti Skyline and a fourth in Moab.
We believe in a strong field-based program.
Avalanche forecasting is more of an art than a science. And because of this, computers never have, and most likely never will, be able to forecast avalanche hazard as well as an experienced and skilled human being. Avalanche forecasting works best when the person putting out the forecast has an intimate, daily connection to the snowpack. We notice that the longer we spend in an office, the more out of touch with the snowpack we become. Therefore we always put in one or more field days before our forecasting shift, and we never have more than two forecast days in a row.
This is our philosophy and it
seems to be working. More people access
the UAFC bulletin each season than any other avalanche advisory in North
America, and the number keep increasing by an average of 20 percent per
year. The numbers of people going into
the backcountry keep increasing exponentially, yet the death rate has risen
more slowly. We also see an increasing
demand for avalanche education and information, not only by Utahns, but by the national
an international media.
We are very passionate about
our work because it’s more than a job, it saves lives.
Nuts and Bolts
The UAC is operationally
separated into four entities:
·
Bear River drainage
(Logan area – northern Utah and southeast Idaho)
·
Wasatch Mountains
(Ogden, Salt Lake, Park City and Provo area mountains)
·
Manti Skyline (Fairfield
Canyon – Wasatch Plateau)
·
La Sal Mountains (near
Moab)
Mike Jenkins heads the Logan
operation with a staff of: Drew Hardesty and Spencer Logan. Mike Jenkins has taught a quarter-long
avalanche class for Utah State University for a number of years and he has
organized a fine consortium of local volunteers, graduate students and
workers. Their office is located at
Utah State University in the Department of Forest Resources and they are all
Utah State University employees.
In Moab, Faerthen Felix is the
program director with a part-time staff of Eric Trenbeath, (who works for Utah
State University) and several volunteer workers. The Moab office is located in the Moab Ranger District on the
Manti-Lasal National Forest.
Faerthen also oversees the
Manti Skyline forecast, which is issued by Craig Gordon and Eric Trenbeath,
both Utah State University employees.
Last, but not least, the vast
majority of the backcountry use occurs in the Wasatch Range of northern
Utah. A staff of six full time workers
cover the Ogden, Salt Lake City, Park City and Provo area mountains—arguably
the most heavily used mountain range in the U.S. Bruce Tremper, in his 14th season, is the
Co-Director along with Evelyn Lees.
This season, Tremper spent most of his time working on Olympic-related
avalanche problems while Lees oversaw the day-to-day operations. The rest of the very experienced staff
include: Tom Kimbrough, Seth Shaw, Ethan Greene and Jeff Brown. All are Forest Service employees under the
Intermountain Regional Office. The Salt Lake office is co-located with the
National Weather Service at the Salt Lake International Airport.
Lastly, a private, nonprofit
group, the Friends of the Utah Avalanche Center, contract the intrepid Bob
Athey as a full time backcountry observer.
Although Bruce Tremper and Evelyn Lees spend most of his time in the
Wasatch operation, they oversee all three operations to insure consistency in
quality.
The Utah Avalanche Center is a
Forest Service program under the Intermountain Region and the Manti-La Sal
National Forest, in partnership with Utah State University, the State of Utah
Department of Public Safety, Division of Emergency Management, Salt Lake County,
the National Weather Service and private contributions through the Friends of
the Utah Avalanche Forecast Center.
The public can access the
bulletins in the following ways:
Telephone:
Salt Lake City - (24 phone lines) (801)
364-1581
Logan (multi-line PBX system
at Utah State University) (435)
797-4146
Park City (multi-line PBX
system at Park City Resort) (435)
658-5512
Ogden (multi-line PBX system
at Weber State University) (801)
626-8600
Provo (multi-line PBX system
at Brigham Young University) (435)
378-4333
Alta (multi-line PBX system
through the Town of Alta) (801)
742-0830
Moab (single phone line) (435)
259-7669
Radio Stations (live on-air reports each morning around 8:00 am)
KRCL 91 FM
KPCW 92 FM
Internet:
http://www.avalanche.org
http://www.wrh.noaa.gov/Saltlake
http://www.csac.org
Fax:
We operate an automated fax
distribution of the bulletin for selected businesses and Forest Service offices
that post a hard copy for the public to read.
To contact our office: (801)
524-5304 (phone)
(801) 524-4030 (fax)
e-mail: uafc@avalanche.org
Season Highlights
Weather and
Snowpack
It was a very warm season with very stable snow. It was the seventh warmest winter on record at the Salt Lake Airport. The snow line remained about halfway up the mountain ranges for most of the season. High elevation areas experienced near normal snowfall but low elevation areas suffered a skimpy season.
Incidents and
Accidents
On a positive note, only two avalanche fatalities occurred this season, which is below the 5-year moving average of 3.4 fatalities per year for Utah. This reflected the national trend of below normal avalanche fatalities. Nationally only 22 avalanche fatalities occurred this season (as of this writing). This is below the national average of 26. Low fatality numbers are attributed to the very warm winter experienced throughout most of the West, which creates stable avalanche conditions.
Media
The national and local media continued its fascination with avalanches. National television documentaries about avalanches continued to play on the Discovery Channel TBS and PBS. Most of these documentaries feature Utah Avalanche Center staff featured in a very positive light. In addition, Bruce Tremper was interviewed this season for yet another national TV avalanche documentary for the Discovery Channel and was the featured guest of the hour-long NPR radio program “Talk of the Nation” and Ethan Greene was interviewed by NPR’s “The Savvy Traveler.” The UAC staff logged 56 media contacts which include one national television interview, fourteen national television requests for information, two national radio interviews, seventeen national print interviews, five local television interviews, six local radio interviews and eleven local print interviews.
Education
Utah Avalanche Center staff taught 54 classes avalanche classes this season, directly reaching a total of 2242 people. These classes range from hour-long avalanche awareness classes to multi-day Level II classes. Each of these classes was specifically tailored to the group ranging from grade school and Boy Scout classes to professional ski patrollers and university scientists.
Snowmobile outreach
Thanks to a grant from the National Recreation Trails Program, we hired Craig Gordon and Eric Trenbeath, to do avalanche education and forecasting specifically for snowmobilers. They taught 18 snowmobile avalanche courses reaching 556 people and issued a weekend avalanche advisory for the Manti Skyline, a popular snowmobile area in central Utah. We hope that this will help to stem the rising tide of snowmobiler avalanche fatalities.
Use of UAC Products – Changing Technologies
Because it was such a dry, warm year, public access of UAC products was down compared to previous years. With rain and green grass in town for most of the winter it’s hard to get very excited about heading into the mountains. Still, the UAC avalanche advisory and mountain weather forecast received more use than for any other avalanche center in North America.
Because of the rise in popularity of the Internet, we have noticed in recent years, that more and more public access the advisories electronically than listen to the telephone recording. We live in an increasingly time-constrained society and now that over half the households have home Internet connections and most people have access to the Internet at work, we can expect the trend to continue. Other avalanche centers have noticed these trends as well.
Technology has changed the way we do business. Although telephone recordings are more personal, about twice as many people access the advisories over the Internet. And a format that works for the telephone does not translate very well to the Internet. Web surfers rarely take the time to read a long-winded page of text. They would rather linger on graphics-intensive pages or bulleted, concise information. This is especially true with young, Internet and MTV-addicted audiences who are also the most likely people to get killed in avalanches. To effectively serve the public, we must change with the times.
This season, we have experimented with web pages that use icons, images and short, bulleted text to convey critical avalanche information. We are also experimenting with a GIS display of avalanche danger. The user sees a computer generated, oblique view of a mountain massif on which the avalanche paths and avalanche danger ratings are draped over the terrain. For instance, the forecast might call for a “high danger on all northwest through northeast-facing slopes above 10,000 feet steeper than 35 degrees.” It’s hard, especially for inexperienced users, to visualize exactly what this kind of terrain looks like or where they would find it. But when displayed graphically, it’s easy to visualize. Avalanche danger is almost never the same in all parts of a mountain range. It varies by aspect, elevation, slope steepness, exposure to wind, anchoring and terrain shape—all very hard concepts to describe with words but very easy to describe with imagery.
The development of this kind of display has so far proved to be too expensive and complex for our meager budget and limited time, but we hope that we will finally have a version suitable for public display by the 200-2001 season.
Use of UAC products has
fallen slightly this season due to the warm, dry winter. As Internet access of the products
increases, call counts decrease.
Season History – Northern Utah
Like most
places in the west, it wasn’t much of a winter. It was slow to start, soon to end and it fell asleep a couple
times in the middle. In addition, at
least at the Salt Lake Airport, it was the seventh warmest winter on
record. The snow line hovered about
halfway up the mountains for most of the winter and significant snow fell in
Salt Lake City only a couple times.
Down in the valleys the grass remained green for much of the winter with
rain more common than snow—nearly as miserable as a winter in Seattle. Elevation was the key. Higher elevation areas ended up with a near
normal snowpack but low elevation areas suffered throughout the winter. As a final insult, April set a record for
the percentage loss of snowpack through melting.
Also,
because of the warm temperatures, the snowpack was solid and stable for an
uncharacteristically large percentage of the winter. There were only two avalanche fatalities in Utah, one in
southern Idaho and only one injury—much below normal for Utah.
November:
November
set the tone for the early season of this below average winter. As late as November 15 there was almost no
snow on the ground at Alta. Several
small storms in the second half of the month added up to about 30 inches of
snowfall, with 20 inches on the ground at the Guard Station at the end of the
month. The east side of the range and
the Ogden and Provo Mountains fared even worse. Snowbasin and Sundance were not open in November and Park City
lost the America's Opening World Cup races, which it has reliably hosted for a
number of years, because it was too warm to even make artificial snow. On the positive side, the lack of snow
equaled a lack of avalanches. In some
years, the early part of the season is a dangerous time, with many people eager
to get out despite unstable snow conditions.
This year, with the lack of snow, people just weren't getting caught. The month ended with 32 inches of snowfall
at the Alta Guard Station.
December:
The snow
pack difference between the Cottonwood Canyons and other parts of the range
became more prominent during December.
Alta had slightly above average snowfall for the month, at 97 inches,
finishing with about 40 inches on the ground at the Guard Station. This provided decent backcountry touring
conditions at mid and upper elevations in the central Wasatch. The eastern side of the range had about half
as much on the ground. Sundance in the
southern Wasatch was able to open with the aid of snowmaking. In the Ogden Mountains, poor Snowbasin was
still constructing their new snowmaking equipment and they lost the entire
Christmas season.
Storms in
the first two thirds of the month finally produced a few avalanches but conditions
were never too serious and no avalanche accidents occurred. There was no precipitation during the final
10 days of the century, giving a restful Holiday Season to the Wasatch
avalanche workers.
January:
The thin
snowpack during November and December provided ideal conditions for developing
the dreaded depth hoar, or sugar snow, near the ground, especially outside of
the Cottonwood Canyons where thin snow provided the perfect metamorphic
conditions. Then the clear weather at
the end of December added a layer of weak snow to the surface of the pack. The missing ingredient was a blanket of more
cohesive snow on top of the various weak crystals. The first 11 days of the new millennium provided just that
blanket.
Most areas
around the Wasatch just about doubled their snow pack during this period,
although that is not saying much for this skimpy season. Unfortunately, the avalanche danger also
increased dramatically. Human triggered
slides became more common and on January 11 tragedy struck. On the 10th the danger rose from
"moderate" to "considerable" and, on the morning of the
11th, to "high." In a very
tragic accident, a married couple, skiing the lifts at The Canyons, decided to
leave the boundaries of the resort and triggered a large avalanche in the
backcountry. They failed to pick up
their young child at the day care that night, and a search team located night
and their bodies the following afternoon.
A couple of warm storms with high elevation rain/snow lines helped stabilize the deeper weak layers in the snowpack during the second half of January. But there always seems to be a trade-off. The warmth also formed slick and hard sliding surfaces. Fortunately a long series of human-triggered slides occurred almost daily, but had no unhappy endings, despite a few close calls.
At the
month's end, winter had returned to the Wasatch—albeit briefly. The snow line was down to the valley floor
and the Alta Guard Station snowfall total for the month hit 114 inches, 18
inches above average.
February:
For the
month of February, the much-anticipated and well-funded IPEX project set up in
the National Weather Service office.
IPEX (Intermountain Precipitation Experiment) funded by a consortium of
federal and university entities, was designed to intensively study winter
storms in Utah for the month of February—not coincidentally, the same month as
the Olympic Games. Dozens of scientists
descended on the National Weather Service office, which we share, armed with a
truckload of computers, a portable Doppler radar and storm chaser aircraft—most
of which sat idle for during the first half of February. The normally reliable computer models
forecasted several storms that failed to materialize over the Great Basin. The scientists in charge of the operation
were looking rather pale as their expensive equipment collected deeper and
deeper layers of dust waiting for the first February storm.
At last a
series of storms arrived that became the largest snow producer of the winter,
although—and it goes without saying--relatively warm for Utah. They didn't provide quite the usual
"greatest snow on earth" but the warmth did reduce the avalanche
danger by speeding the stabilization process within the new snow.
The weak
early season snow, still hiding underneath the January and February deposits
tossed in isolated wild cards.
Occasionally someone would trigger a slope that would break down into
these deep layers, a fact that we grew tired of repeating in our avalanche
advisories. Several people had close
calls from these deep slab avalanches and on February 19 a snowmobiler was
killed just north of the Idaho border as a large avalanche broke to the
ground.
This
season's snowiest month finally pushed the total depth at the Alta Guard
Station over the 100-inch mark with a well above average 119 inches.
March:
The winter
began tapering off in March. One decent
storm arrived on the 8th and 9th of the month, along with several weaker
systems evenly spaced over the remaining weeks. Temperatures were rather warm (of course) and the high sun angles
triggered shallow wet slides as skies cleared after the storms passed but
generally avalanche activity was at a minimum.
Snowfall
numbers remained slightly below average 88 inches for Alta. The total depth at the Guard Station dropped
below 100 inches on March 22, beginning an inexorable decline.
April:
Following
the tapering off period in March the winter came to an early close in
April. April is often a wet month in
Utah, but not this season. Only 15 inches
of snow fell at Alta, over 50 inches less than normal, off by 78 percent. So what else is new?
The sunny
days did provide a fine melt-freeze cycle and mostly cool nighttime
temperatures gave good corn snow skiing and boarding for the first half of the
month. The warm winter also had
increased snow pack densities increasing the quality and distribution of the
corn. But there was the inevitable
trade-off; the hot sun had baked off most of the southerly facing slopes by the
end of the month.
For a seemingly
short and warm winter the final numbers weren't that bad. The average total snowfall at Alta is right
at 500 inches. This year's inches added
up to 446, only down by 11%. But the
numbers were very elevation dependant.
The lower elevation resorts had significantly below normal snowfall,
especially at their base.
The
snowpack in April melted at a record pace.
Which didn’t surprise anyone.
Season History – La Sal Mountains – by Faerthen Felix
September
Labor Day’s customary snow appears a couple of days later than expected, and much heavier than is usual: 8” instead of the expected dusting. Taken as a sign of things to come, this harbinger hits the nail on the head with the timing of winter’s arrival, which was considerably later than normal. In fact, we wouldn’t see another snowflake until late November. When winter finally arrives, will it be as heavy as the early snow predicts?
October
The summer lingers, not that anyone seems to mind. Perpetually cloudy July and August gave us more than our annual precipitation needs, so the late-season sun is embraced by everyone. Surprisingly, there is no new snow in the mountains this month, and the September snow gradually fades away, leaving a clean (and stable) slate for winter’s eventual arrival.
November
A spectacular Indian Summer persists and, pleasant as it is, it begins to feel unnatural and creepy as the end of the month approaches. Finally, a trace of snow touches the high mountains on the 20th, followed by 9” on the 22nd. Temperatures remain mild, so the snow settles rapidly rather than faceting into a dangerous weak layer. Some skiing and sledding can be done on the Geyser Pass road, but the pack is far too shallow to allow backcountry turns or avalanches.
New staff arrives at the MLSAFC for the season. Peter Hawkins from the University of Bath joins us as our intern, and Eric Trenbeath takes on the role of Assistant Forecaster and Snowmobile educator for Southern Utah.
December
Snow begins to gradually slink in as the month progresses, but it’s more of a fan-dance tease than anything else. A trace falls on the 1st, 7” arrives on powerful winds on the 3rd and 4th, another trace on the 8th. It’s always two steps forward and one back as the new snow settles, rots or blows away before it can fill in the ground surface texture.
4” on the 10th, 1” on the 12th, 4” on the 13th and 3” on the 20th provide enough snow to keep the roads covered above the parking areas. It’s not enough to keep the 4WDs and ATVs out, so tempers flare as motorized and non-motorized recreationists find themselves in close proximity. On the positive side, the additional traffic helps pack the snow on the roads and keep it in place. New Year’s Eve brings the last storm of the Millennium and 4” of new snow, but avalanche hazard remains spotty and confined to cross-loaded gullies way above timberline.
January
The New Year’s Eve storm lingers and delivers another 19” before it’s done. Some steep pockets run during the storm and on test slopes immediately after, but even with the copious new load the surface texture provides anchoring and the lack of a smooth bed-surface holds most of the new snow in place, despite weak facets on the ground.
A bureaucratic snafu results in the MLSAFC Avalanche Forecasters being laid off on the 14th. The UAFC sends Forecaster Jeff Brown down from Salt Lake City to cover while the US Forest Service--led by Moab/Monticello District Ranger Glen Casamassa--performs miracles to resolve the problem. What could have served as a convenient excuse to axe the entire program turns into a great day for the MLSAFC as the District commits to create a permanent seasonal position for the Lead Forecaster.
During the administrative tempest, 5” of wet, heavy snow arrives on the 17th, ahead of a cold snap that finally creates a supportable base. Jeff presides over the season’s first off-road turns as 2” falls on the crust on the 20th. The regular staff returns to 4” on the 21st and another 1” on the 23rd. Avalanche conditions become devious, considerable and widespread with the new snow load on the fragile buried slab. The straw that breaks the camel’s back comes with 8” of new snow on the 25th and 26th and cold temperatures that chew away at the new snow bond. Large natural avalanches release on virtually all aspects, some stepping down to the ground. Plenty of slabs remain, jus