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occasionally usesthisterrainforspecial eventssuchas
the powder eight competitions in Cody Bowl.
Within the boundaries of the resort are many restricted
access areas that are not presently accessible from the ski
lifts.Much of this terrain is comprised of the startingzones
of majoravalanche paths that overhang open areas of the
resort and therefore the reduction of the avalanche hazard
ontheseslopesispartofthedailyavalanchehazard
reduction effortsof the resort.Thisterrain is not part of
the alpine touring area anda separate accessmanagement
plan has been developed forthis terrain.Public access to
these areas is believed to improve the safety of the resort
due to the increase insnowpack stability achieved by skier
compaction.
ACCESS MANAGEMENT CRITERIA
Criteria have been established forthe management of pu-
bic access to the touring areas.The primary condition for
access requires thegeneral regional avalanche hazard to
be evaluated as low by BTNF avalanche forecasters.The
definition oflowhazard is mostly stable snowexist and
avalanches are unlikely except in isolated pockets.
Secondary criteria foraccess assessvisibility,skicon-
ditions andmanpower(incidentresponse)capabilities. The
touring terrainconsists of cliffs, rockbands, cornicedridges
and steepsnow-coveredslopes many of whichendin hang-
ing snowfields.No routes are marked andno warningsigns
existsinthisterrain,thereforegoodvisibilityhasbeen
establishedasone ofthe conditionsforpublic access to
theseareas. In addition,the availabilityof patrol manpower
for in-areaand out-of-arearesponse is a consideration with
respect toopening the touring areas.An incident in the
touringareastypicallyrequiresfourpatrolpersonnelto
address anyinjury.Thedispatchingofmorethanfour
patrollers to the backcountry has a significant impact on
theresponsecapabilities ofthepatroltotoppriorityin-
area incidents.
Poorski conditions in the backcountry which are not
hazardous with respectto avalanches may greatlyincrease
thepotentialforuserinjuryand associatedpatrolman-
powercommitment.Therefore,incasesofpoorsnow
conditions accessto the touringterrain may beclosedsolely
forpotential injury hazard.
FORECASTING
Daily avalanche forecasting is conducted at the laboratory
locatedatthe baseoftheresort.Thebackcountryfore-
casts are an extension of the daily forecast required by the
forest service to manage the avalanche hazard within the
resort.
Avalancheforecastsare developedbasedon dataderived
from snow study plots located at the base of the resort and
remotelyobtaineddatafromsnowstudyplotsand
instrumentation located upon the mountain.Thisinfor-
mationissupplementedbyweatherforecast,snowpack
stability considerations and by observations of avalanche
activity within the forecast region.
A base elevation study plot allows forthe observation
of24hoursnowfallaccumulations and associatedsnow
density on a snowboard.Daily snowpack depth measure-
ments are recordedto determine 24 hour snowpack settle-
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ment.A modified tipping rain gauge at this plotrecords
the moisture associatedwith newprecipitationevents.The
correlation of the moisture data from the rain gauge with
the snowfall,temperature and density measurements ob-
tained from this study allows the forecasters to judge the
reliability of the raingaugemoisture datafor specificevents
and to relate this data to remotely obtained data from other
study plots inaccessible in the early morning hours.
Three other study plots are located upon the mountain.
Instrumentation at these remote locations transmit a con-
tinuous recordof temperatureand moistureassociatedwith
snowfall to the laboratory.At one of these plotsa television
camerafocusedonalightedsnowstakerecordsnew
snowfallwithinthelast24hours.Wind speedisalso
continuouslytransmittedtothelaboratoryfromthissta-
tion, and a continuous record of wind direction and speed
parameters is obtained from instrumentation near the top
of the resort.These instruments continuously record total
miles of wind and the intensity of wind gusts.
These data sources are supplemented by communica-
tion with snow grooming personnel who are on the moun-
tain allnight, instrumentationon thetramwaytowers which
record temperature, wind speed and wind direction at six
locationsandvisualobservationsifpossible.Afterthis
datahasbeenobtained,evaluatedand processedintoa
forecast,hazardreduction measuresaredevisedforthe
resort and instituted byski patrolhazard reduction team
leaders.The results of these efforts are documentedby the
forecasters,entered into the historical record and consid-
ered in the re-evaluation ofthe forecast forthe next day.
Studyplotsare thenvisitedtocompare theremotedata
obtainedtorealtimedataobtainedfrom24hour
snowboards and snowstakes.
A computerhistorical search program has been devel-
oped based on accumulated data obtained during 31 years
ofoperation.Byinserting storm-specificmeteorological
data and snowpack information, this program allows fore-
casters to obtain information regardinghistorical avalanche
eventsintheresortandthe backcountryduring similar
conditions.This program provides a good forecasting tool
especiallywhencomplexconditions arisefrom an extended
active avalanchecycle.
Backcountry forecasting was developed in 1975 forthe
BTNF in a standard format and is provided to the public
on a phone message and on a form which is transmitted by
facsimile to various public and private entities located in
western WyomingandeasternIdaho. Theseentities include
the local media, sports shops, ForestService districtoffices,
snowmobile clubs, theNational Outdoor LeadershipSchool
(NOLS),motelsand sponsors.Theforecast isbroadcast
daily on the local radio station and is also accessed via the
Internet.Forecastsareissuedby7:00AM.Forecasts
providegeneralavalanchehazardconditionsforthe
morningandafternoonatthelower,midandupper
elevations.The forecast region is comprised of an area of
approximately 15,000 square miles.During the1995-1996
seasonabout90,000telephonecallsweremade bythe
public to obtain the forecast report.
The forecast laboratory isentirely financed by private
donations and corporate sponsors.The funds provided by
these entities are placed in an account which is used by
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