Table Of Content

A57.46/3:2000/1 Montana —Natural Resources Conservation B~"W "Vas•m Outil"| oo"k| R~%eport, January 2000 1 , Basin Outlook Reports and Federal -State - Private Cooperative SnowSurveys Formorewatersupplyandresourcemanagementinformation,contact: SeeAttachedList Howforecastsaremade MostoftheannualstreamflowintheWesternUnitedStatesoriginatesassnowfallthathas accumulatedhighinthemountainsduringwinterandearlyspring. Asthesnowpack accumulates,hydrologistsestimatetherunoffthatwilloccurwhenitmelts. Predictionsare basedoncarefulmeasurementsofsnowwaterequivalentatselectedindexpoints. Precipitation,temperature,soilmoistureandantecedentstreamflowdataarecombinedwith snowpackdatatopreparerunoffforecasts. StreamflowforecastsarecoordinatedbyNatural ResourcesConservationServiceandNationalWeatherServicehydrologists. Thisreport presentsacomprehensivepictureofwatersupplyconditionsforareasdependentupon surfacerunoff. Itincludesselectedstreamflowforecasts,summarizedsnowpackand precipitationdata,reservoirstoragedata,andnarrativesdescribingcurrentconditions. SnowpackdataareobtainedbyusingacombinationofmanualandautomatedSNOTEL measurementmethods. Manualreadingsofsnowdepthandwaterequivalentaretakenat locationscalledsnowcoursesonamonthlyorsemi-monthlyscheduleduringthewinter. In addition,snowwaterequivalent,precipitationandtemperaturearemonitoredonadailybasis andtransmittedviameteorbursttelemetrytocentraldatacollectionfacilities. Bothmonthly anddailydataareusedtoprojectsnowmeltrunoff. Forecastuncertaintyoriginatesfromtwosources: (1)uncertaintyoffuturehydrologicand climaticconditions,and(2)errorintheforecastingprocedure. Toexpresstheuncertaintyin themostprobableforecast,fouradditionalforecastsareprovided. Theactualstreamflowcan beexpectedtoexceedthemostprobableforecast50%ofthetime. Similarly,theactual streamflowvolumecanbeexpectedtoexceedthe90%forecastvolume90%ofthetime. The sameistrueforthe70%,30%,and10%forecasts. Generally,the90%and70%forecasts reflectdrierthannormalhydrologicandclimaticconditions;the30%and10%forecasts reflectwetterthannormalconditions. Astheforecastseasonprogresses,agreaterportionof thefuturehydrologicandclimaticuncertaintywillbecomeknownandtheadditionalforecasts willmoveclosertothemostprobableforecast. TheUnitedStatesDepartmentofAgriculture(USDA)prohibitsdiscriminationinitsprogramsonthebasisofrace,color,nationalorigin,sex,religion, aalgtee,rndaitsiabvielimtey,apnoslitfiocralcobmelmiuenfiscaantdiomnariotfaplroorgfraammiliianlfosrtmaattusi.on((NBoratilallel,plraorhgiebiptreidntb,aasuedsioatpappley,teotca.l)lsphroouglrdamcso.n)taPcterUsSoDnAs'wsitThAdRisGabEilTitCieesntwehroatre2q0u2ir-e720- 2600(voiceandTDD). 7T2o0-fi1le1a27co(mTpDlDa)i.nt,UwSrDitAetisheanSeecqrueatlareympofloAgyrmiecunlttuorpep,orUt.uSn.itDyepeamprltomyeenrt.ofAgriculture,Washington,D.C.,20250,orcall1-800-245-6340(voice)or(202) UnitedStatesDepartmentofAgriculture NaturalResourcesConservationService(formerlytheSoilConservationService) Bozeman,Montana Where to Get More Information BeaverheadCounty FallonCounty LewisandClarkCounty VictorHager AnnFischer LexRiggle 683-3805 778-2217 449-5278 BigHornCounty FergusCounty LibertyCounty DicksieMichael TheodoreHawn DawnWickum 665-3442 538-7401 759-5778 BlaineCounty FlatheadCounty LincolnCounty MatthewCrampton MaryPochelon KirkSullivan 357-2320 752-4242 296-2233 BroadwaterCounty GallatinCounty MadisonCounty KellyMorris GordonHill MikeBarron 266-3146 522-4018 842-5741 CarbonCounty GarfieldCounty McConeCounty GregoryEvertz ClarenceClayton ReganFanning 962-3641 557-2232 485-2744 CarterCounty GlacierCounty MeagherCounty WayneYost MarkJohnson OttoOhlson 775-6355 873-4292 547-3633 CascadeCounty GoldenValleyCounty MineralCounty MartyMetz JohnRouaneJr. JoeWang 727-7580 323-2103 251-4826 ChouteauCounty GraniteCounty MissoulaCounty SandySmith AnnetteJohnson JoeWang 622-5627 859-3291 251-4826 CusterCounty HillCounty MusselshellCounty TerryHeck JamieSelting JohnRouaneJr. 232-7905 265-6792 323-2103 DanielsCounty JeffersonCounty ParkCounty StanleyFrench LaurelOvitt RonHoagland 487-2872 287-3215 222-2899 DawsonCounty JudithBasinCounty PetroleumCounty LindaPeterson-Lohse RickCaquelin KarenBrady 365-5566 566-2311 429-6646 DeerLodgeCounty LakeCounty PhillipsCounty GlenGreen DavidWolf LornaPhilp 846-1703 676-2841 654-1334 (over) PonderaCounty RosebudCounty TooleCounty LannyWalker RockySchwagler MistyPeterson 278-3922 356-7333 434-5234 PowderRiverCounty SandersCounty TreasureCounty CarolHilliard DonFeist StewartGreer 436-2417 826-3701 342-5510 PowellCounty SheridanCounty ValleyCounty GlenGreen TimSolberg NormaVanNostrand 846-1703 765-1801 228-4337 PrairieCounty SilverBowCounty WheatlandCounty BobProngua LaurelOvitt JohnOiestad 635-5381 287-3215 632-5534 RavalliCounty StillwaterCounty WibauxCounty LaneJohnson PhilipSandoval KatrinaJohnson 363-5010 322-5359 796-2211 RichlandCounty SweetGrassCounty YellowstoneCounty KimWhipple DanGlasgow ShadWeber 433-2110 932-5160 657-6135 RooseveltCounty TetonCounty RobertBray DanBloedel 787-5232 466-5722 p 11 U.S.r^/^ENTOFACKICULTURE NATURALRESOURCESCONSERVATIONSERVICE! O Z 3O»5 >•i « ':\>*PO»t CoO jI>1 > — m m O y\ 1° (to m SNOWWATEREQUIVALENT "On EXTREMELYABOVEAVERAGE(OVER150%) MUCHABOVEAVERAGE(130-150%) 1I0SO0SKTIALTOUMTEETEMRISLES CURRENTASOF ABOVEAVERAGE(110-130%) o AAlpteprrso*EqSucaalleA:re1a'Projection JANUARY 1,2000 HINBEEALROWAVAEVREARGAEGE(9(07-01-1900%%)) —> SInOfUoRrCmEationprovided NDPoaRttOeaV:IuSsIaOdNAtoLgaannderSaUtBaJtEhCisTmTaOpCHoArN*GE. 1^MUCHBELOWAVERAGE(50-70%) > byNRCSSnowI HflEXTREMELYBELOWAVERAGE(BELOW50%) Personnel FT1NOMOUNTAINSURVEY NRCSSTATEOmCE.BOZEMAN.MT.CRASS/UAPCEN«.1/mtn»ww.lOOAw JANUARY2000 IU.S.DEPARTMENTOFAGRICULTURE NATURALRESOURCESCONSERVATIONSERVKEI CANADA CO H 00 v-/ "0 «i Q 7oJ §. co tO m | o 1 TJ CO O 2. 73 STREAMFLOWPROSPECTS EXTREMELYABOVEAVERAGE(OVER150%) MUCHABOVEAVERAGE(130-150%) > ABOVEAVERAGE(110-130%) CURRENTASOF AlbersEquolAreaProjection JANUARY1,2000 NEARAVERAGE(90-110%) > oxScale:1:4,300,000 BELOWAVERAGE(70-90%) Note: SbIyOnUfNoRRrCCmEaS:tiSonnopwrSouvirdveedy DPaRtOaVIuSsIeOdNtAoLgaennderSaUtBeJtEhCiTsmTaOpCHaArNeGE. MEUXTCRHEBMEELLYOWBEALVOEWRAAGVEER(A5G0E-7(0B%E)LOW50%) Personnel. NOTFORECAST NRCSSTATEOFFICE.BOZEMAN,UT.CRASS/MAPCEN4,1/«tmo».100.bw JANUARY2000