756 FXUS04 KWBC 202157 QPFPFD QUANTITATIVE PRECIPITATION FORECAST DISCUSSION NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD 456 PM EST FRI NOV 20 2009 FINAL DAY 1...DAY 2 AND DAY 3 QPF DISCUSSION VALID NOV 21/0000 UTC THRU NOV 24/0000 UTC REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR THE 18Z NAM AND GFS CONTD TO SHOW THE SAME SOLNS THEY HAD ON THEIR RESPECTIVE 12Z RUNS..SO MADE ONLY MINOR CHGS TO THE PRELIM DAY 1 QPF..BASED MSTLY ON RECENT RADAR/SATL IMAGERY/TRENDS. DAY 1... ...NERN U.S.... CLOSED LOW AND ASSOC COLD FRONT WILL BE CLEARING NRN NEW ENGLAND EARLY IN THE PD. EXPECT SOME LGT WRAP-AROUND SHWRS THOUGH TO PERSIST OVER THE OROGRAPHICALLY FAVORED TERRAIN...FROM THE ADIRONDACKS OF NY NEWD UP INTO NWRN MAINE. ...WRN/CNTRL GULF COAST REGION.... SURGE OF DEEP MSTR NWD ACRS THE WRN GULF AHEAD OF S/WV TROF PUSHING EWD ACRS THE SRN PLAINS WILL CONTINUE TO FUEL LOCALLY HEAVY RAINS EARLY IN THE PD ALONG THE S TX COAST...BUT THIS FOCUS OF CONVECTION SHOULD TEND TO SHIFT RATHER QUICKLY OFFSHORE AS A COLD FRONT CLEARS THE REGION. MORE SIGNIFICANT UNCERTAINTY THOUGH WILL UNFOLD FOR THE CNTRL GULF REGION BY THE END OF THE PD AS THE MDLS SHOW A FAIR AMT OF SPREAD REGARDING HOW THE S/WV TROF LIFTS NEWD ACRS THE GULF COAST. THE 12Z GFS CONTINUES TO BE THE MOST PROGRESSIVE WITH THE ENERGY AND ESP THE SFC LOW THAT TRACKS ACRS THE NRN GULF OF MEXICO. THE NAM IS THE SLOWEST...WITH THE 00Z ECMWF AND 12Z GEM GLOB SPLITTING THE DIFF. THE NAM ALSO IS SUFFERING FROM AN EXTREME AMT OF CONVECTIVE FEEDBACK AND SINCE IT ALREADY IS MISHANDLING THE CONVECTION OVER SERN TX AND THE WRN GULF OF MEXICO...HPC OPTED TO DISCOUNT ITS SOLN ENTIRELY. GIVEN THE SOMEWHAT FASTER TREND SEEN IN THE GFS TO ADVECT MOISTURE AND ENERGY NEWD OUT OF THE GULF AND ACRS THE DEEP SOUTH ALONG WITH DECENT RUN TO RUN CONTINUITY...HPC OPTED TO LEAN MORE PROGRESSIVE WITH THIS SYS...WITH A SOLN ESSENTIALLY SPLITTING THE DIFF BETWEEN THE 12Z GFS AND 00Z ECMWF. THE GFS IS LIKELY PULLING ITS HEAVIER QPF A LITTLE TOO QUICK TO THE NORTH CONSIDERING THE AMT OF LOW LVL RIDGING/DRY AIR IN PLACE INITIALLY ALONG THE CNTRL GULF COAST AND WITH THE FACT THE MAIN BAROCLINIC ZONE IS CURRENTLY WELL SOUTH DOWN OVER THE CNTRL GULF OF MEXICO. THIS WILL GRADUALLY MOVE NEWD TWD THE COAST AS SFC LOW PRESSURE BECOMES BETTER ORGANIZED IN RESPONSE TO THE APPROACHING S/WV TROF...BUT THE STRONGEST FORCING IS LIKELY TO STAY ALONG OR JUST OFFSHORE THE GULF COAST INVOF THIS BNDRY AND SO THE HEAVIEST RAINS WERE KEPT SOMEWHAT MORE SUPPRESSED AT LEAST FOR THIS PD. ...WRN U.S.... MODELS ARE VERY SIMILAR HERE IN PROGRESSING FAIRLY HIGH AMPLITUDE UPR TROF EWD ACRS THE WEST COAST AND THRU THE GT BASIN REGION EARLY IN THE DAY 1 PD...WITH A SECOND UPR TROF QUICKLY FOLLOWING AND ARRIVING ALONG THE PAC NW COAST BY THE END OF THE PD. BEST MSTR INFLOW AND UPR DYNAMICS WILL FOCUS INITIALLY OVER THE NRN SIERRA-NEVADA AND INLAND ACRS THE SAWTOOTH/BITTERROOT RANGES OF THE NRN ROCKIES WHERE MDT TO LOCALLY HVY SNOW WILL BE POSSIBLE. THEREAFTER...MDT TO HVY OROGRAPHICALLY DRIVEN RAIN AND SNOW SHOULD IMPACT THE COASTAL RANGES OF WA/OR...INCLUDING THE OLYMPIC PENINSULA AND ALSO SPREADING INTO THE CASCADES AS THE NEXT FRONTAL BAND AND ASSOC UPR SUPPORT ARRIVES. A CONSENSUS OF THE HIGHER-RES 12Z NAM/00Z ECMWF WAS FOLLOWED HERE FOR THE QPF DETAILING. DAYS 2/3... ...PAC NORTHWEST INTO INTER-MOUNTAIN WEST... A STRONG PAC H5 SHRTWV WILL ALREADY BE AFFECTING THE NORTHWEST AT THE START OF THE PD LATE SAT...ACCOMPANIED BY A STRONG CDFNT SWEEPING THROUGH THE REGION SAT NIGHT/SUN. A RATHER PERSISTENT/STRONG ONSHORE FETCH BEHIND THE FNT WILL RESULT IN HEAVY RAINFALL AND MTN SNOWS ACROSS WA/OR THROUGH SUNDAY. HPC HAS INDICATED 1-2 INCHES IN THE HIGHER ELEVATIONS...AND A HALF INCH ACROSS THE LOWER ELEVATION. THE MSTR/INSTABILITY AXIS WILL SHIFT EWD SUNDAY/MONDAY THROUGH THE NRN ROCKIES ACCOUNTING FOR UP TO A HALF INCH OF RAINFALL OR SNOW-LIQUID-EQUIV. ACTIVITY WILL TAPPER OFF FROM W TO E SUN EVENING/MON AS A SHRTWV RIDGE BUILDS BACK OVER THE WEST. YET ANOTHER SYSTEM WILL IMPACT THE NW LATE IN THE PD...BUT THE SIGNIFICANT RAINFALL WILL STILL BE IN B.C. MONDAY AFTERNOON. MODEL GUIDANCE OVERALL IS IN DECENT AGREEMENT AND HPC GENERALLY FOLLOWED THE 00-12Z ECMWF AS A BASE WITH HELP FROM THE ENSEMBLE QPF AND PRISM. ...NRN/CNTRL PLAINS... UPR TROF WILL PROCEED INTO THE PLAINS DAY THREE AND INDUCE SFC CYCLOGENESIS LEE OF THE CNTRL OR NRN ROCKIES...MODELS ARE NOT QUITE SURE YET. REGARDLESS...A BAND OF WAA PRECIP SHOULD DEVELOP ACRS ERN DAKOTAS/MT ON MONDAY AS THE UPR TROF APPROACHES...THEN MORE DYNAMIC PRECIP WILL DEVELOP UNDER THE TROF ON MONDAY FROM CNTRL ROCKIES EWD DEPENDING ON THE SFC CYCLONE EVOLUTION. HPC USED A 12Z ECMWF/ENSEMBLE BLEND HERE. ...CNTRL GULF COAST THROUGH SOUTHEAST AND MID ATLANTIC... TREMENDOUS DIFFERENCES CONTINUE REGARDING THE PROGRESSION OF A SFC WAVE AND UPR ENERGY INVOF NE GULF SPREADING UP THROUGH THE SOUTHEAST AND OFFSHORE MID ATLANTIC. GFS CONTINUES TO BE THE FAST OUTLIER...YET THE TREND IS TO BE MORE PROGRESSIVE THAN BEFORE WITH THE 12Z CAN GLBL/UKMET AND 15Z SREF LENDING SOME SUPPORT TOWARDS A FASTER SOLUTION. MEANWHILE THE 12Z ECMWF HAS TRENDED IN THE OPPOSITE DIRECTION WHILE THE NAM REMAIN SLOW. ALL THIS ADDS TO A HIGHLY UNCERTAIN DEPICTION OF POTENTIALLY MDT RAINFALL FOR A SIZABLE PORTION OF THE SOUTHEAST AND CAROLINAS. HPC HAS CHOSEN TO TAKE AN APPROACH FASTER THAN THE ECMWF...BUT NOT AS FAST AS THE GFS...EVEN THOUGH NONE OF THE DETERMINISTIC MODELS TAKES THIS APPROACH. DRASTIC DIFFERENCES ALSO EXIST UPSTREAM IN THE NORTHEAST/SRN NEW ENG ON MONDAY AS THE FASTER SOLUTION ALLOW PRECIP TO SPREAD NWD...WHILE THE SLOWER SOLUTIONS SHUNT PRECIP OFFSHORE. FOR NOW...HAVE GONE DRY IN THE NORTHEAST. ORRISON/TERRY/SOWKO GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV 24HR QP VT 22/00Z 0.01 522684 519674 516667 513660 511658 508645 505636 502628 498619 494614 488609 479605 475605 471606 453620 435625 425633 421638 419641 418646 417652 419659 422666 430672 436673 447673 454677 458684 458693 457696 451700 449705 441710 439713 440721 440732 438737 433742 431746 431753 432758 434761 437763 442760 448751 451748 454746 457745 463751 469759 473763 476766 482766 485765 493758 502748 508738 513728 518715 520706 522693 522684 0.01 525256 522253 518251 516244 514238 514233 513228 506219 500208 496204 493203 483200 477201 473203 467205 462203 451207 450205 449200 454197 460190 464187 468182 471179 475179 478180 482185 489187 491189 493194 497195 504194 508198 512202 516204 519209 523214 528213 533209 535203 536198 536193 535186 530179 529172 526164 522161 517154 512151 500142 495138 491132 487128 480125 477123 473119 472113 472108 471103 467101 460099 455096 450092 444092 440091 433091 427089 420102 418107 414106 410102 406102 400111 398113 398118 404121 414130 417133 419137 419141 417147 415150 412157 411168 410177 412185 414190 423195 431189 435194 437201 437207 435209 432210 429207 426203 424200 422200 417204 410205 402202 388194 373185 363181 361184 360186 362190 366196 364201 360204 354205 351205 350211 353215 357217 380214 385215 392217 401224 400227 397228 394230 393235 396241 400245 406248 412250 414252 410257 397276 395282 395288 398296 401301 404304 407304 412303 422298 429294 438289 457279 463277 468277 474278 480279 486281 489284 496290 503296 507297 510296 0.01 441129 442125 440122 434124 431125 428128 425135 423139 422146 423154 425159 429162 432160 430155 430147 432140 434136 437132 441129 0.01 367965 366958 364956 359950 355946 352944 349944 346942 340943 336944 332944 328939 327934 328931 336918 340911 341905 340884 340874 341868 345859 345850 344845 342840 337836 331833 325831 318829 311829 304827 298823 289816 283811 287809 288804 281800 276798 269797 266798 266802 271806 275808 271812 269817 274822 279826 285832 289838 290843 290848 289853 285860 280865 274868 268873 260885 254896 249910 242921 240927 239936 240942 242947 246952 247957 246961 244968 245974 250982 254985 260987 267988 275988 280991 287996 293998 307991 315988 319985 325979 332976 336977 339979 345980 354978 360975 365969 367965 0.25 489635 486630 481625 476624 471626 468631 467635 468640 472648 477652 481656 485665 484681 481694 480702 482707 484708 489708 493704 497697 500689 500681 499673 494656 490638 489635 0.25 512280 513273 513268 511261 509253 508243 506234 503227 496213 493210 489208 482206 475207 469210 466211 462211 457213 451215 446217 439218 434222 435226 439229 442231 441235 439239 437242 435250 430256 426259 421265 418270 417276 418278 421280 426280 436275 446269 457263 463260 469259 477262 484267 493277 499283 505285 510283 512280 0.25 520187 518180 515176 507168 499168 490162 485156 473152 470149 466145 459144 451150 447150 443149 438148 436152 435153 435157 438160 445166 451174 456164 461161 465166 469171 470171 475169 481172 483175 489175 495178 498181 503183 508187 511189 515190 520187 0.25 487228 486226 483224 481222 478223 475223 472224 474226 477226 480227 483230 485231 487228 0.25 489139 486136 485134 483133 480133 478133 475133 477136 480136 483137 483138 486141 489140 489139 0.25 409230 411222 410218 405215 401212 397208 394205 391206 392210 396213 399217 404220 405225 405231 408231 409230 0.25 388205 388201 387199 384197 381194 379193 376193 374195 375196 376199 378201 379203 380204 383206 385207 388205 0.25 325870 324864 322862 317859 310855 303855 297867 292871 289872 282875 277879 272884 268890 265896 262903 260909 257915 255922 253929 253938 257945 263950 269952 272956 270962 268966 271970 276974 281977 294970 298963 302963 307962 309961 312958 313954 315939 318923 319905 320896 321889 324879 325870 0.50 505277 507272 507268 505262 501257 499251 495245 492240 488236 482236 478229 474229 468230 464230 463227 464224 469219 472219 485219 488215 485211 482209 478209 474211 464217 459217 455220 456224 459227 461229 459229 454234 451236 447237 446240 445249 442254 440258 440261 447262 451260 459255 463254 470254 476256 482260 491269 499277 505277 0.50 471158 470157 468153 467153 465151 462151 459152 461154 463157 464158 467160 470161 471158 0.50 451221 448220 445220 444220 445223 448224 451221 0.50 314884 314875 310869 307865 302863 296872 286877 281881 278884 276890 273894 269898 267903 263913 259923 259929 261936 263940 267943 276945 278953 278957 274962 274966 282971 287968 291964 296954 302946 306941 308936 312924 314914 314906 314901 313890 314884 1.00 499265 496259 495254 493249 490243 487240 484242 480239 477234 475233 471236 470240 472243 474247 480249 485253 487256 492262 495265 499265 1.00 305903 304899 303894 303891 302887 299885 297889 292893 289896 284899 280900 277902 273906 271911 266919 266926 269933 275931 279928 290927 297926 301923 303918 305913 305903 1.00 298937 297934 296935 292940 291943 287946 285946 283950 281956 279963 281966 285965 289959 291954 294948 297941 298937 1.50 296912 295909 293906 292906 289906 286906 284908 281909 280909 281912 281916 282916 286918 288917 291916 292916 294916 295915 296914 296912 1.50 287959 287955 286953 285956 285959 287959 287959 24HR QP VT 23/00Z 0.01 524261 522250 519238 515228 512217 512213 515214 517217 523223 531227 536221 537215 537204 530184 525168 523163 520160 514153 508148 499142 486130 475124 468119 471111 470106 466103 463101 459102 454099 447093 433092 428089 426089 424092 428100 421103 415111 412110 410107 410101 406100 403106 400108 398113 398118 403119 411121 414122 417126 418132 417140 416144 414146 406152 404155 406156 408155 412156 414172 413178 415183 418188 424192 428191 431188 435189 435195 436199 435205 429203 426199 421198 411200 408202 405203 395201 392202 390206 390210 392213 395220 395222 392223 385225 384231 386235 395249 400254 406257 410260 414262 419263 423262 430263 435262 440263 446261 455261 458261 463260 469262 480266 488274 494282 498287 503290 508291 512290 0.01 495877 495874 491869 488870 484872 475882 469888 465890 460891 453893 447899 442906 437913 432916 429918 426921 421928 416934 408945 405952 404958 402961 396973 390979 389983 391988 395992 401993 407989 412984 421974 431962 441954 448948 456946 463945 472940 484930 490925 490922 490915 490908 492904 495895 496885 495877 0.01 437132 437126 434124 431124 428130 427135 424142 423146 423154 426156 427151 430145 433140 435136 437132 0.01 382757 378751 372746 362738 357733 353730 348726 344724 339724 336727 332735 331741 330749 330755 329762 327768 324772 321778 316784 309790 306792 300791 295790 290789 287790 284798 283806 283814 282819 277821 271820 267818 262813 259809 256809 254812 255817 259823 265831 262839 260846 261851 263856 262863 261869 260876 261880 265885 270887 293896 312906 322916 327920 333922 340921 345916 352907 359892 362885 363877 365872 365866 367859 370851 372847 376838 380823 390800 390796 389792 385787 382781 380773 382757 0.25 515272 517267 516263 515254 512241 509230 505219 500205 497199 500194 505193 510196 519202 522201 523196 522192 520187 517180 513175 510172 502165 494155 490153 486152 476153 468147 465146 461146 456150 453151 449150 441145 438145 435148 434152 434156 438161 445170 448179 447183 444187 441195 441206 440210 437211 431211 427211 425215 422220 421225 416228 410230 408233 407238 408245 411249 414252 419254 425255 435254 444253 452251 463251 468251 472250 476252 482254 487260 492267 499278 504281 506282 510280 514275 515272 0.25 476189 476185 474180 470179 465182 462184 458187 455191 454197 457198 460198 466197 469195 472193 476189 0.25 359781 350766 348763 344763 340766 338769 331784 325797 321803 313808 306811 297814 295817 294821 292828 288841 284848 283855 284863 287872 292880 296885 300888 306890 321894 331900 335899 338897 342889 344882 349877 353871 358863 359857 359848 357837 357826 361814 362810 361803 359800 355799 354798 357794 360788 359781 0.50 510270 511262 510256 507245 503229 499218 495208 492203 489198 486197 484199 477203 471206 465208 459207 453209 449210 446212 440214 432216 426222 426231 420232 414233 411237 412242 419248 425251 431251 440249 447248 460246 464245 468242 471240 475240 479242 483240 483235 481231 478228 477224 482225 485228 486229 489227 491230 492235 493239 496245 499250 503252 508259 507265 500261 499266 503271 507273 510270 0.50 492248 493244 493242 490242 487242 489244 492248 492248 0.50 350822 347809 338810 334809 328811 324814 318815 309815 301817 298825 296833 295838 294843 290850 290856 292862 296870 299875 303877 309880 316880 321877 325875 331873 337871 342869 347863 351859 353854 354846 353838 351831 350822 1.00 499232 498225 496220 490216 488213 485209 481209 476211 473213 471215 472217 478219 484221 490222 492226 494231 497234 499232 1.00 464238 464233 462229 465223 464217 462215 458215 453218 456226 455231 449234 442236 438238 439241 447241 454240 460240 464238 1.00 430244 430243 430240 428237 425236 422237 420237 419237 417240 418242 421244 423246 426246 430244 430244 1.00 341830 338825 333823 321823 316822 312822 310827 309833 306845 304850 300854 301861 303864 308867 313864 318861 324859 331855 334851 337846 339841 341834 341830 1.50 334836 334832 332830 328829 324829 319829 317832 315836 314841 314847 317852 320854 326852 330848 331844 333840 334836 2.00 325839 325836 324836 323836 322837 320840 319841 320845 321845 324844 325843 325839 325839 24HR QP VT 24/00Z 0.01 524252 520245 517239 513227 509220 502208 504201 505201 510203 515209 520217 525220 529220 533212 534205 534200 532191 529185 524179 513170 506165 499163 485161 482161 481159 479155 476154 474148 474145 476145 485147 491151 498154 500154 500149 500145 498140 494136 489131 484129 475124 469123 464128 460131 456130 451133 449135 445134 443138 440140 437142 436147 436153 441156 445157 454165 457168 457170 455176 446187 446191 449193 456190 465182 469177 472171 478165 480170 481173 482178 487182 491184 492187 492193 489195 484197 479199 472202 468205 464206 460205 454211 452213 450216 450219 451222 454225 456227 456231 451231 445232 443234 442239 444246 448250 453251 461255 464260 470267 478276 484282 494290 502294 511296 0.01 501889 501880 501875 499872 491869 485868 480870 471880 467888 461895 450909 443916 440922 442929 441936 438947 433956 426961 419965 413970 411973 406976 398979 395979 392983 389987 387991 386997 384017 382027 378036 379042 381046 382052 386056 387060 384064 383065 378061 379054 375050 373050 370055 367065 369069 370074 371081 373086 377090 380090 383094 387096 390095 395094 400096 401099 392109 389112 384113 379115 377120 374125 374129 375132 379135 385135 388135 393132 401130 405130 408129 412128 414128 417129 422140 423135 424132 427128 431124 435122 440122 445124 448125 451123 455122 458116 458113 465115 469115 470112 470106 465102 456098 454092 454083 453079 450073 446067 442065 437065 433065 430060 425054 421050 421047 423042 427038 429035 429031 427024 425020 425014 425001 426998 429996 436992 446988 456985 461983 467979 475973 481966 486957 489948 492938 494926 497909 501889 0.01 422702 422697 419693 418692 415693 407705 388723 381726 376725 365721 361721 355724 349728 344732 337740 330752 322771 319777 316781 305791 302794 299799 299809 296814 293819 282828 277835 279840 283842 287844 295843 303839 308839 310845 314849 321855 331861 341865 351866 358866 363862 365857 366853 364849 361843 360836 369829 372824 377820 382820 385817 389810 391804 394798 395793 398780 400775 404769 411757 416746 417740 417732 415723 415717 417713 422702 0.01 439084 439080 438080 434082 432080 428078 424079 418084 416091 415099 415103 418103 423099 424094 422089 424084 433087 436088 439084 0.01 419158 419154 419150 421146 418145 418146 418150 417153 416157 417161 419158 0.25 520264 518258 515251 508237 505230 501224 494214 490214 486211 483208 478211 475216 474221 472225 468231 464236 463239 465243 467246 471250 480262 488270 498282 505287 512287 516284 0.25 479905 479901 478901 476906 476907 479906 479905 0.25 477959 474955 470954 469952 469947 469942 468935 467936 462940 460942 454951 448961 442967 439972 439975 440977 443978 447977 452975 463972 472966 475963 477959 0.25 390772 389764 385755 378747 375744 370741 363740 356742 350745 341753 334762 331770 327782 326786 322790 314798 312806 313814 316822 323830 326832 332831 337828 342827 354825 359822 361819 369810 375803 383792 387783 390772 0.25 414010 415006 413003 410003 407005 406007 406011 406015 408019 411017 413014 414013 414010 0.25 415072 414064 410061 407060 403061 399064 398068 395071 392071 389072 387077 386083 389086 395085 401084 404080 407079 411076 415072 0.25 410034 410030 409026 408026 406024 405026 403030 403031 401034 400036 399038 400039 403039 406039 408038 409036 410034 0.50 515277 516271 516266 514258 512251 509245 501233 497231 495235 495240 487237 484237 480236 476233 472236 472242 476248 480253 489265 496276 500281 507284 512281 515277 0.50 369756 367751 363749 359748 354749 348752 342760 337770 333778 332787 332790 335792 339794 347794 351793 354791 358786 363783 366776 368765 369760 369756 1.00 508264 508258 506251 504247 501249 495247 490243 486242 484245 485251 488256 492262 495267 497271 499275 504277 505267 508264 $$