FXUS04 KWBC 170652 PAA
QPFPFD

 
QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
251 AM EDT FRI SEP 17 2004
 
PRELIM DAY 1 AND DAY 2 QPF DISCUSSION
VALID SEP 18/1200 UTC THRU SEP 19/1200 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR
 

DAY 1...


...ERN U.S....
HEAVY RAINS ASSOCD WITH TD IVAN WILL CONTINUE TO SPREAD NEWD
FROM THE TN VALLEY INTO ERN PORTIONS OF THE OH VALLEY INTO THE
MID ATLC REGION AND SRN NEW ENGLAND.   MODELS CONTINUE TO COME
INTO BETTER AGREEMENT IN TAKING MID LEVEL CENTER NEWD ACRS THE
SRN APLCNS BEFORE SLOWING/STALLING OVER VA/NC AS HEIGHTS BEGIN
TO BUILD RAPIDLY OVER THE CNTL U.S.  SYSTEM WILL CONTINUE TO TAKE
ON MORE OF A BAROCLINIC LOOK WITH UPR TROF MOVING ACRS ERN
CANADA ALLOWING HIGH PRES TO BUILD OVER THE GT LAKES AND
STRENGTHENING FRONTAL ZONE TO THE NORTH OF IVAN ACRS OH INTO
SRN NY.  THE ABOVE FRONT WILL EVENTUALLY BECOME A STG FOCUS
FOR HEAVY RAINS AS STG SELY FLOW TO THE EAST OF IVAN DRAWS
DEEPER TROPICAL MSTR INTO THE BNDRY.   THOUGH ITS QUITE CLEAR
THE MORE SIGNIFICANT RAINS WILL SET UP TO THE N AND NW SIDE OF
THE MID LEVEL LOW TRACK...THE BIG QUESTION AT THIS POINT IS WHERE
WILL THE STG DEFORMATION BAND SET UP.  WHILE THE GFS HAS SHOWN
THE BEST CONSISTENCY...BELIEVE IT IS A BIT TOO FAR NORTH WITH ITS
DEFORMATION BAND.   THE MM5 AND NGM BOTH SUPPORT KEEPING
HEAVIER RAIN AXIS SOUTH OF THE GFS.  AMOUNTWISE..THE ETA LOOKS
UNDERDONE GIVEN ITS POOR INITIALIZATION OF PWS IN THE SE.  
CONSENSUS OF NGM..MM5..AND GFS SUGGEST POTNL FOR A STRIPE OF 4
TO 5 INCH PLUS RAINS FROM SERN OH THRU MUCH OF SRN PA INTO NRN
NY/SE NY.  FARTHER SOUTH...SOME UPSLOPE COMPONENT WILL
CONTINUE INTO THE MTNS OF WRN NC AND WRN VA AS LOW CROSSES
TO THE EAST SIDE OF THE APLCNS...SUGGESTING A SEPARATE QPF MAX
THERE UNDER PERSISTENT MOIST INFLOW..THOUGH NOT QUITE AS HEAVY
AS OVER THE NRN MID ATLC.  EVEN THE WEST SIDE OF THE SRN APLCNS
IS EXPECTED TO SEE A PD OF MOIST WLY/NWLY UPSLOPE CONDS AS LOW
TRACKS NEWD...AS THE MODELS SEEM TO CAPTURE FAIRLY WELL.   

...PAC NW...
WEAK TO MDT POST FRONTAL ONSHORE FLOW ALONG WITH AMPLIFYING
S/WV TROF FCST TO MOVE INTO THE PAC NW COAST FRI NIGHT WILL
COMBINE TO PRODUCE SOME  LIGHT TO MDT RAINS AND PSBL HIER ELEV
SNOWS PRIMARILY FROM THE CASCADES WWD TO THE COAST.   EXPECT
ADDITIONAL RAINS/HIER ELEV SNOWS  FARTHER INLAND OVER THE NRN
INTERMOUNTAIN REGION WHERE A WEAK WAVE IS LIKELY TO DVLP ALONG
THE FRONT IN RESPONSE TO APCHG S/WV TROF.   USED A MODEL BLEND
GIVEN DECENT MODEL AGREEMENT AND MINOR QPF DIFFERENCES.  

CNTL U.S...
EXPECT SOME SCTD SHWRS/TSTMS TO DVLP ACRS ERN PORTIONS OF THE
CNTL PLAINS LATE IN THE PD IN RESPONSE TO STRENGTHENING LOW
LEVEL JET/WARM ADVECTION PATRN.    MODELS GENLY AGREE
THAT ACTIVITY WILL NOT BE VERY WIDESPREAD..THOUGH
SOME .25 INCH AMOUNTS ARE PSBL VCNTY NE KS/NW MO.

DAY 2...
IVAN WILL DISSIPATE IN THE SOUTHERN APLCNS...VIGOROUS S/W AND
DEEP MOISTURE FROM IVAN INTO COLD FRONT WILL BRING PCPN INTO
NEW ENGLAND EARLY SATURDAY THEN CLEAR...JAVIER WILL BRING PCPN
INTO THE SW...MARITIME LOW PRES MOVING INTO NW WILL GENERATE
PCPN IN COASTAL ZONE AND CASCADES OF WA/OR.

BOUNDARY LAYER MOISTURE CONVERGENCE INDICATES THAT PCPN IN
SOUTHERN NEW ENGLAND WILL END EARLY SAT AND BE PRIMARILY
OFFSHORE BY SAT AFTN. THE GFS TAKES THE REMNANTS OF IVAN A LITTLE
FURTHER NORTH THAN THE TPC/HPC FORECASTS AND PROBABLY BRINGS
THE MOISTURE A LITTLE FURTHER NORTH THAN EXPECTED. HENCE WE
WILL TREND A LITTLE LESS WITH QPF OVER SOUTHERN NEW ENGLAND.

EVEN WITH IVAN DISSIPATING IN THE SRN APLCNS THERE WILL STILL BE
AMPLE MOISTURE AND TERRAIN ENHANCEMENT. INLAND CAROLINAS ARE
NOT DONE WITH IVAN AS QUICKLY AS THE ETA WOULD HAVE YOU BELIEVE.
WE WILL TILT MORE TOWARD THE GFS FROM SC TO VA.

THE IMPACT OF JAVIER IN THE SW...SPCLY IN AZ...COULD BE
SUBSTANTIAL.
CURRENT TRACK IS A LITTLE SLOWER THAN THE GFS...BUT THE GFS IS
MOVING IN THE RIGHT DIRECTION. ETA LOSES THIS FEATURE AND SHOULD
NOT BE THE BASIS FOR QPF IN THE SW. THE FLOW THROUGH THE
BOUNDARY LAYER IN THE GFS AND THE PW VALUES ARE NOT
SIGNIFICANTLY HIGHER IN THE GFS...BUT THE DYNAMICS INDICATE THE
GFS IS MORE ON TRACK WITH THE QPF. QPF WILL BE LESS THAN
INDICATED IN THE GFS DUE TO TIMING...BUT SUBSTANTIALLY MORE THAN
INDICATED BY ETA.

SAT INDICATING A SECONDARY SHOT OF COLD AIR SUPPORTING THE LOW
OFF THE NW COAST. ALTHOUGH THE COLD SHOT MAY CAUSE THE LOW TO
STALL OFF THE COAST THERE SHOULD BE ENOUGH ENERGY TO PROVIDE
PCPN...SNOW...INTO THE CASCADES. HEAVIEST PCPN IN COASTAL OR...BUT
A SECONDARY MAX IN THE WA CASCADES. MOISTURE ADVECTION INTO
THE INLAND NW LOOKS WEAK

SULLIVAN/KELLY

GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV
 
24HR QP VT 18/12Z
 0.01 533215 535209 535202 534195 530178 528168 524162 520156 
      515149 509147 503143 498140 495132 495125 499117 505101 
      506082 506070 506067 504068 495079 491083 487083 483081 
      479081 476086 473093 468098 465105 462112 459118 455125 
      450129 446130 442132 441135 437141 435158 428171 425176 
      424181 424185 426190 430194 437197 441202 443203 442207 
      434207 429209 423213 419217 410222 408224 408229 408233 
      409238 411242 416247 428254 435257 443258 471263 474264 
      479269 484273 490279 494282 500282 503283 506282 511277 
      513267 514261 513256 515250 516247 515228 513218 510208 
      514206 517208 522213 525216 529218 533215 
 0.01 450652 442653 436653 432656 430659 422668 418674 410683 
      405690 397698 381711 373717 364723 350732 334746 278790 
      272796 267799 260799 252804 249806 251812 252817 254821 
      254823 252828 252830 254831 260826 263826 265828 272831 
      274840 273846 270852 267860 265870 268880 270882 273880 
      284870 289865 296860 310848 312847 315848 320851 331861 
      338866 344868 351872 360872 376868 382864 384861 388858 
      391854 394853 400844 410830 417814 421805 424797 429780 
      436759 440743 443733 444724 443704 444690 446679 448666 
      450652 
 0.01 518978 518970 518962 517953 515945 511913 507903 501893 
      497884 493873 491870 487870 485872 480878 477886 474895 
      472905 472914 475920 476923 479928 484935 490942 494951 
      497954 499960 504967 510976 513979 517981 518978 
 0.01 470197 472189 470185 468184 462185 458186 455190 451192 
      447195 445203 447208 453210 456209 459206 463203 466200 
      470197 
 0.01 466936 466931 466927 463919 461915 459910 455905 452903 
      449902 443903 440906 440913 442917 443925 446928 450936 
      453939 457940 463939 466936 
 0.01 419963 420955 418947 416944 411941 407939 404939 401936 
      398937 395937 392935 389935 386936 380934 377935 375938 
      376945 379950 386957 392960 395963 398963 401966 404966 
      410968 416967 419963 
 0.01 343157 340154 336152 324148 321146 319140 321124 323118 
      325114 328110 332107 335105 338099 338093 336089 335085 
      329082 322083 316082 310082 305085 303090 300094 296104 
      296113 300123 303133 303139 302146 304152 307156 315162 
      319165 325167 334163 339162 342159 343157 
 0.25 520191 519186 518181 517175 514170 510165 501158 494155 
      488152 485149 482144 480138 480129 480124 481121 480119 
      477115 472118 465124 457135 445154 440165 439171 443170 
      446171 450176 453176 457171 464161 470159 476161 479164 
      482170 485176 489179 500186 505190 511192 517193 520191 
 0.25 498255 500248 502241 501232 500228 497217 495211 491208 
      485203 480203 477205 464213 448220 441220 436221 433222 
      427242 437245 446245 454246 463247 472249 479252 488257 
      493258 496256 498255 
 0.25 438676 438670 435667 432668 428671 419683 414690 411696 
      405710 398723 393735 389741 385747 379751 374752 351747 
      345749 337753 324761 314769 311773 307779 307781 309781 
      315780 321778 328778 331780 329786 326793 326799 327803 
      327805 323812 319816 314821 304829 301832 296838 297841 
      298840 303836 310832 314829 321825 326821 332821 335826 
      336835 340842 349851 359859 365859 372858 379854 384849 
      390845 395840 399835 403828 409816 415804 421790 425776 
      428762 431746 435715 436705 437694 437682 438676 
 0.25 406950 405949 403947 402946 399945 396947 395949 396950 
      398952 400953 403954 405952 406950 
 0.25 283815 280813 279813 277811 276811 273809 270809 267809 
      264810 264813 266815 266816 269816 271817 272817 275817 
      277817 278817 281818 284817 283815 
 0.50 434688 433684 431681 427683 421692 413702 408712 399731 
      394742 392747 389751 384756 379757 369757 361757 356754 
      352753 343755 333760 324766 321770 325770 333768 338769 
      339777 343783 345788 346796 346802 347813 346825 346836 
      349841 353845 359852 362854 368854 379850 389843 396835 
      401826 407817 412806 420787 423774 425765 427751 429741 
      431717 434688 
 0.50 482245 482240 481239 479235 477234 476233 475233 473234 
      471236 471241 472242 474245 477246 480246 482245 
 0.50 470136 469131 466133 463135 459139 456143 453147 450153 
      449159 452163 458160 461156 463153 466149 468140 470136 
 1.00 427711 426705 423704 419706 416709 411715 408724 403737 
      395751 391756 384762 376767 368772 363783 358790 359799 
      358806 354812 352818 351825 351831 352835 357838 363841 
      368844 374846 382844 389840 394834 401822 408807 414793 
      420777 422763 425745 427730 427719 427711 
 1.50 425717 423713 421712 416714 413719 409727 403739 398752 
      393758 389763 380774 378780 375786 365797 361810 357815 
      354820 354825 357829 362830 365831 367833 373835 379836 
      378840 385839 389838 392835 395830 399824 405812 411799 
      416785 419772 422755 424741 425726 425717 
 2.00 422719 419716 416717 415720 409733 404744 397756 391764 
      383776 379787 376792 369795 367798 366801 366807 366815 
      361820 363822 370821 373824 373828 379829 384827 386830 
      385832 386835 390835 394830 397825 402814 408802 413789 
      416777 419764 421751 423736 423726 422719 
 2.00 386806 385805 382807 381808 380810 379812 377817 376819 
      380818 381815 384812 385811 385808 386806 
 3.00 419726 418725 416727 414731 409741 405750 399759 394766 
      390777 389781 391784 393790 393795 393801 391806 394814 
      392823 391827 394827 402810 407800 411790 413781 415771 
      418748 420738 419726 
 3.00 375803 374800 371801 371802 370806 373808 375804 375803 
 5.00 409762 408762 406763 405764 404767 403769 402772 401774 
      404777 406773 406772 407768 408767 409762 409762  
 
24HR QP VT 19/12Z
 0.01 224071 239092 247102 255110 257113 257117 250119 243121 
      239125 235132 234138 234145 235152 238158 241165 244169 
      250174 258176 266178 276179 284179 300178 306178 314176 
      328172 339166 346162 353160 370158 376158 381158 385155 
      388148 390142 392130 397124 410116 416112 419109 421104 
      421091 427084 432078 438072 442065 445058 445051 445046 
      443043 438041 429041 391044 382043 375040 370040 363041 
      350049 337055 330058 323060 317062 308063 301061 294057 
      283049 272041 267038 260036 253036 245036 228038 
 0.01 569945 566942 563943 556945 551945 547940 543933 539928 
      536924 535919 534918 531918 529921 526925 519936 514949 
      512956 511960 511971 513982 518995 522008 523013 523019 
      521025 514035 511041 508049 503059 502063 497068 489074 
      485077 479080 468081 466081 463084 459089 452097 449101 
      444105 435124 431135 428142 427152 426160 428167 433171 
      440171 443170 447174 450179 454184 459184 462181 469173 
      472171 476170 479172 483176 485183 486185 485189 482191 
      474199 454202 445205 441207 435206 429207 425207 414209 
      404211 395214 390217 386223 382233 382239 384244 390251 
      395255 402258 404264 404269 405276 407281 410285 415287 
      418288 420290 424299 427303 430304 435304 441302 445300 
      454296 463290 470285 479279 495272 500270 504267 512261 
      521253 525247 527242 532227 534216 535210 534204 534197 
      533187 533169 532150 530139 523127 515119 507113 505108 
      506099 509095 513100 519108 525116 531126 538151 542161 
      544165 546167 549166 
 0.01 408627 405635 404640 400645 391653 381661 362676 354683 
      348689 338697 332704 325710 316718 305730 299737 293744 
      267770 256782 244793 236799 233807 230813 231819 234822 
      241828 248831 253836 259840 262840 267838 274832 285819 
      288813 290809 290805 291801 295797 302792 313787 323781 
      325779 326782 324785 321794 317802 315813 317817 319822 
      325828 332831 335832 339836 343846 350853 376829 391815 
      394810 397808 399804 402802 404797 415781 424766 429756 
      432747 441727 444717 449705 454687 460664 463654 465643 
      467631 469618 470608 467599 464597 460597 451598 436599 
 0.25 565052 563047 559042 557037 554027 553011 551005 548005 
      546007 540018 535028 530039 526049 523055 521063 529070 
      538074 546078 552081 555085 559087 562083 
 0.25 456616 452611 446610 439612 433614 426619 418627 412637 
      407646 400658 389670 375685 368690 358697 343706 329718 
      317729 311735 305742 301747 297753 293766 287778 286781 
      285784 288786 291786 296784 323769 332764 339761 348760 
      355760 347771 342784 338791 332796 328803 326807 326811 
      327814 331819 338823 343827 346834 348835 353834 361829 
      367822 375815 384805 393794 396784 397776 395754 394749 
      397747 403747 414754 420751 425744 431726 436710 442694 
      453656 456647 458637 458626 456616 
 0.25 515238 515229 514219 512211 510207 509203 506196 502197 
      496200 489202 482202 477203 464210 454214 447216 440218 
      436222 432228 429233 426235 422235 416236 414238 413243 
      414251 416260 418266 421271 426277 428280 431282 435280 
      439276 449266 459258 470251 480245 486243 495245 504248 
      509248 512245 514240 515238 
 0.25 520196 520192 520187 520182 519177 519174 517172 516170 
      513169 512171 510173 509175 507179 506180 505183 505188 
      506193 507197 510198 511199 513202 516202 519201 519200 
      520196 
 0.25 481116 482111 481108 480106 476103 472101 467103 463106 
      458112 451122 442133 440137 436144 436149 436154 438157 
      441158 450155 459145 467136 475127 479122 481116 
 0.25 410083 410076 407072 405071 397069 389069 364053 357054 
      354060 350067 347071 345073 341072 336072 327075 319077 
      311077 305078 293083 287084 282081 276077 270072 265061