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<br />Wyo,ling. :''WSw3cnlngssrecaIledtotheconsc!ltsnt,IoIho, lntc!ra,
<br />furnishes spotter reports.
<br />
<br />d"velopi~.g self-contained local IoI>>r"ing systems. the ",xtent 0< these
<br />proars." t. limited byllvailllble reaource". In the C8.chel<.tPo"dre
<br />RiVer ~aatn, " XWS forec~~ting ,able hs, been developed for Ruattc,
<br />Eor1nt"r""1,,seby the Denver 'il3FO. The t"hle relates" range of
<br />""nerall.edrainfalldtstri.butlo""onlhebasinupstre.l<lfroclRustict0
<br />resulting snealllfto'" "t 1!.uHic. to help c"librate the tables, the
<br />'''''SllS City RFC issues, t",ice ",eokly, a aotice of the ratnfdl needed
<br />over a period of 3 hours or So to produce ban~full stage. In various
<br />Front ~nge canyon <lrea3. This is kn""'n as a Headwater Guidan".. Advtsory.
<br />
<br />Ratnfllll report" "'".e fragmentary or no"nxtlltent ~cause of
<br />telep~one faIlures during the 1971; Hig Thompson iU.H flood. tn the
<br />sparsely populat..d ~untains, if the diatance hetween spotters is more
<br />than<lbo'Jt>nUles, the:najorpart of a Big Thoill.pson Rtver ryp"storlll
<br />:nay not be reported.
<br />
<br />Experience ~ith the XWS .potter tlCt"'ork indiCllte. regular telephone
<br />eontacrisnec..ssarytokeepthe.ysteOlllctiveandthis l.snotal"'ay.
<br />possible. (lntervte", ",ith Mr. Larry Tunnel, nenver '~eather Service
<br />Forecast Office, 20 Dece~ber 1979). The spotter networks have proved
<br />useful in the more densely populated plains area around the City of
<br />119)
<br />FortCoHins.' lnthe Boulder area, the
<br />ters declined 1n the last few
<br />
<br />spot-
<br />years to about one-third of theort,!:1nal
<br />the Boulder County Fire Depan..e"t).
<br />
<br />"um~er of interested
<br />
<br />Records are published for strea~ gages on the main stem at the
<br />canyon ~outh and on the South Fork near its mouth. The streaa gage at
<br />the C":'Iyon ~outh 15 read by the State of Colorado. It i. also read by
<br />the XWS by ..atelttte. Aitogether the ~ational We"ther Service Owns ""d
<br />oper"te~ five 8-inch ratn gauges, t"'o automated rai" gauges and one
<br />auto~ated stre"~ gaug.. on the C,"che la Po"dre River tn Larimer County.
<br />Data fro~ the <luto~ated gauges are .vailable at Denver approximately
<br />eve'y 2 hours and dau froathe8-1nchr"ingauges isavatlableupon
<br />request. Ihis data ts shared ",tth L"ri~er County's private weather
<br />consultant. Costs of flash flood detectio"alternHive" ""re cOlllpllted
<br />.iehollt as.u~1ng the use of c~t.ting gng~s.
<br />
<br />number (with the exception of
<br />
<br />The ~S forecast1n" .ygte~ is ""other ~easure for flash flood
<br />dete~tton. At the Nnt10nal Meteorological Center in ~~ryland, ~eather
<br />l"""...ly..,donasy"opti<:scale (iarilesc..le) basis and rain fore C30ts
<br />are issu..d to River Fore<:ast Cent"r~ (RfC's) and ~eather servtce fore-
<br />casr offt~eo (WSFO's) .cross ehe country. The RFC's prepare stage
<br />forecasts prilll1lrily for ,.ajor ri...en "'ith lead U1lIeS of 12 hnurs or
<br />mar". The RFC Can provide fla.h flood guida:'lce for use by th~ WSFO
<br />based on ~asln configurattQn "nd antecedent mlnfan. However, the
<br />
<br />local IISPO 10
<br />\o1<1rnlnl\".(28)
<br />
<br />reopon$ibl" fot 1S9Ui,,& fla~h flood "'atche. and
<br />for the Cache 1... P"udre River Main, the RFC is at
<br />
<br />Satellites. Tech"iques for e~t1~ating ~onvectivc 01 thunders eon.
<br />rainfall using satellites have been developed ia recent yeaes. One
<br />~1dely used technique use" infrared a"d vloihle image" of cloud pat-
<br />tern, from ~ geosynchronous (sta~tonary) sa(~Lllte. Two satetlit~~
<br />operated hy NOAA ~re referr~d to as GOES, (G~ostattonary ~p~ratton<ll
<br />Environmental Satellite). Re~olution Is t~'R cap.,btlity of dtst~n8utsh-
<br />ing elMely adjacent object". In photography, it telat"s to the ftne-
<br />nes~ of detail ~i~ible, ~esolu:lon of GOES satellltas facit1tie. i"
<br />
<br />K3~sas C~ty, ~is"c~r~. ~o ~SfO 15 at D"nv"r.
<br />
<br />I'I addition to spotter "et~orks and foreRIIsts, the NWS ",lght aid
<br />\1\ fL1Sh flo~d det~c:io" by ~rovidin" flash. :~~('~ " ,._ .
<br />F '" ~ ., ~,~. '. Sc rea", gag"s,
<br />'-['ll~'lif!ed f_~r~castI1g charts f?r h)~,,1 '_\~", and ,lSst.tllnc~ In
<br />
<br />1 kilnr-oeter (0.6 ",i1e) at "1slhle ~av~ lengths ~"d S :dlo",.,t~u (5.0
<br />"'tl~s) h 1nfnr"d. 1!.,li-'lOurly ~lct~<"s "ho.. (h~ growth ()f ~')ld t""'p~r-
<br />atllre dQ"d top. and ralnhll h related to this updraft. Th~ tal"fall
<br />
<br />"
<br />
<br />;g
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