FXUS04 KWBC 041000 PAA
QPFPFD
 
QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
458 AM EST FRI APR 04 2003
 
FINAL DAY 1...DAY 2 AND DAY 3 QPF DISCUSSION
VALID APR 05/1200 UTC THRU APR 07/1200 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR
 
DAY 1...

BOTH THE 0600 UTC ETA AND GFS WERE SLIGHTLY SLOWER WITH THE SFC
LOW FCST TO WORK ITS WAY ACROSS THE NRN OH VLY/LOWER LAKES
DURING THE PD.   THE FINAL DAY1 QPF ACCOUNTED FOR THIS MINOR
TREND...AN MORE IMPORTANTLY...CURRENT OBSERVATIONAL DATA.

...ERN HALF OF THE NATION...

MODELS ARE IN GNRL AGREEMENT THAT A  BROAD SHRTWV TROF WILL
ADVANCE EWD FM THE CNTRL U.S. DURING THE FCST PD WITH SOME
AMPLIFICATION EXPECTED IN THE NRN PORTION OF THE SYSTEM AS IT
MOVES INTO THE GREAT LAKES REGION.   DESPITE GNRL MODEL
AGREEMENT ON MASS FIELD FCSTS...THE QPFS ARE NOT IN GOOD
AGREEMENT.   PREFER THE ETA QPF OVER THE UPPER LAKES...THE NRN
PORTION OF THE OH VLY...AND THE NERN U.S.   IT SEEMS HERE THE ETA
HAS A BETTER HANDLE ON DEFINING TWO STRIPES OF PCPN.  THE FIRST
SHOULD BE ASOCTD WITH THE DYNAMIC FORCING EXPECTED WITH THE
MID LVL CLOSED LO FCST TO BE OVER THE GREAT LAKES BY THIS EVNG. 
MUCH OF THIS PCPN WILL BE IN THE FORM OF SNOW...PLEASE SEE LATEST
CCCQPFHSD DISCUSSION AND ASOCTD GRAPHIC PRODUCTS. 
MEANWHILE...THE ETA QPF ALSO SEEMS TO DO BE DOING A BETTER JOB 
HANDLING PCPN EXPECTED ALONG THE STRONG BAROCLINIC BAND AHEAD
OF THE SFC LOW WHICH IS FCST TO TREK NEWD ACROSS THE OH VLY
INTO THE LWR LAKES AREA.   STG MSTR CNVGNC SHOULD BE SUSTAINED
ALONG THIS BNDRY AS FVBL SOUTH TO SWLY LLVL FLOW RESULTS IN A
SGFNT MSTR FLUX IMPINGING ON THIS FEATURE.   FINALLY...BOTH THE
ETA
AND GFS INDC THAT SGFNT SHWR ACTVTY WILL DVLP AHEAD OF THE
TRAILING CDFNT AS IT ADVANCES ACROSS PORTIONS OF THE OH...LWR
MS...AND TN VLYS.   BASICALLY MODELED THE QPF TO REFLECT THE PSN
OF THE CDFNT WHICH WILL HAVE THE AID OF FVBL UPPER LVL DIV TO
ENHANCE SYNOPTIC SCALE FORCING.   IN ADDITION...THE SPEED MAX NOW
BEING OBSERVED IN STLT IMAGERY MOV ACROSS THE SRN ROCKIES
SHOULD SERVE TO ENHANCE LIFT ACROSS THE LWR MS AND TN VLYS
ENHANCING CNVCTV RAINS THERE. 

...WRN U.S..

MOST SGFNT ACTVTY IS EXPECTED WITH THE UPPER VORT EXPECTED TO
BE OVR NRN CA BY THE BEGINNING OF THE FCST PD.   THE MODEL QPFS
ARE IN RELATIVELY GOOD AGREEMENT ON THE QPF GENERATED BY THIS
FEATURE.   OTHERWISE...WE WILL SEE LOTS OF VERY LGT TO LGT PCPN
ACROSS MUCH OF THE WRN U.S. AS GNLY WEAK PIECES OF SHRTWV
ENERGY ACT ON MARGINAL PW TO GENERATE SHWRS.

DAY 2...

...PAC NW...
GFS IS MUCH STRONGER AND SLIGHTLY FASTER WITH VORT
APPROACHING PAC NW CST TWD THE END OF THE PD.  CAN AND UKMET
ARE MORE SUPPORTIVE OF THE ETA SOLN.  HOWEVER...THE DIFFS IN THE
QPFS ARE MINIMAL.

...GRT BASIN...
GFS IS MUCH STRONGER WITH A S/WV MOVG FROM THE SW TO THE CNTRL
PLAINS THAN THE ETA.  THE ETA HAS MORE S/WV ENERGY OVER WY/NE/SD
BY 60 HRS THAN THE GFS.   THE GFS APPEARS TO BE HAVING SOME
FEEDBACK PROBS...SO HAVE GONE CLOSER TO THE ETA SOLN.  THE CAN IS
MORE SUPPORTIVE OF THE ETA WHILE THE UKMET SUPPORTS THE GFS.

...SRN PLAINS...
MDLS DEVELOP A SFC LOW IN CO AND MOV IT SEWD TO THE SRN PLAINS
BY 60 HRS.  THE GFS IS FURTHER N AND DEEPER WITH THE LOW.  THE
STRONGER AND MORE NLY SOLN IN THE GFS IS A RESULT OF THE
STRONGER S/WV IN THE GFS MOVG INTO THE SRN PLAINS.  ALL OF THE
MDLS INCREASE MOISTURE OVER THE AREA ON GOOD SLY FLOW IN
EXCESS OF 40 KTS IN SOME AREAS.  PWS INCREASE TO 1.25 INCHES OR
GREATER.  HOWEVER...DESPITE THE MASS FIELD DIFFS...QPFS ARE
SIMILAR IN THE AREA.

...SERN CONUS...
GFS IS HAVING SOME LARGE FEEDBACK PROBS ERLY IN THE PD...AND
HAVE GONE CLOSER TO THE ETA HERE WHERE THE OTHER MDLS
SUPPORT THE ETA SOLN.

...NERN CONUS...
THERE ARE SOME TIMING DIFFS WITH THE UPR TROF AND S/WV MOVG
OVER NEW ENG.  THE GFS IS FASTER AND STRONGER WITH THE SYS.
THERE IS GOOD VV ACRS THE AREA AND JET SUPPORT.  AGAIN...DESPITE
THE MDLS DIFFS...MDL QPF AMTS ARE CLOSE.
 

DAY 3...

MAIN WX STORY THIS PD IS THE SFC LOW MOVG INTO THE SERN CONUS
AND TN VLY.  GFS IS FASTER/FURTHER N WITH THIS FEATURE.  LL JET
WINDS IN EXCESS OF 40 KTS IN THE SE WILL BRING MOISTURE INTO THE
REGION.  GOOD LL CONV AND UPR DYNAMICS ARE ALSO PRESENT AND
WILL HELP ENHANCE PRECIP TOTALS.  GFS DEVELOPS MANY SPURIOUS
VORTS AND IS HAVING FEEDBACK PROBS.  IT HAS A VERY STRONG VORT IN
AL/GA TWD THE END OF DAY 3 AND THIS S/WV LIKELY ACCOUNTS FOR THE
MORE SLY PLACEMENT OF THE PRECIP MAX IN THE GFS. HVY RAINS LIKELY
IN THE SE WITH AMTS AOA 3.00 INCHES IN TN WITH AMTS ABV 2.00
INCHES
OVER ERN AR/NRN MS/NRN AL/NRN GA AND TN.

ELSEWHERE...SOME RIDGING MOVES INTO THE W WITH THE NEXT SYS
APPROACHING THE PAC NW AND SWRN CAN.  OMEGA IS VERY STRONG IN
THIS REGION AND UPR JET SUPPORT AND ONSHORE FLOW IMPROVE WITH
TIME.  

KORTY/NIERENBERG

GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV

24HR QP VT 05/12Z
 0.01 536206 538198 538191 535184 528169 525164 523159 521158 
      514152 510147 505144 498141 487131 484128 481126 478126 
      470125 468123 467119 472117 473114 476107 475101 479098 
      481093 481087 477078 474072 471068 452053 451030 448026 
      443023 424005 417002 412003 410008 412014 414021 416024 
      415029 408035 403038 394040 386034 382035 380037 378044 
      377052 381055 384071 381076 380082 383087 385085 388083 
      392086 397088 401086 404086 405090 401098 395102 392107 
      383113 380115 378118 374123 372129 372134 373138 376143 
      381147 385149 391155 392157 391160 388164 385170 386178 
      391179 396180 403180 411181 413183 413188 409193 405188 
      393193 388190 382186 369181 364182 360181 357184 359188 
      363192 366200 368204 360202 355202 351200 348203 350210 
      354220 358226 362230 371236 379239 386241 396250 407252 
      415253 422253 429254 434253 441254 446254 459255 467257 
      475261 482264 488269 498279 502282 506283 510280 514275 
      516272 518265 519260 519253 516246 512232 508227 506220 
      502213 499208 495205 494201 493196 490194 485193 482196 
      475196 469197 466200 460199 460194 461190 465183 469179 
      475180 478183 489191 496193 501191 505191 509192 512194 
      513197 519205 522208 526211 533210 536206 
 0.01 464698 461686 458677 455669 450662 446654 442649 437644 
      433640 428640 424644 419655 413668 409678 406686 405692 
      402703 398715 396728 395741 392751 388762 384773 380781 
      377785 371794 363802 354811 345817 340820 336824 330831 
      326834 322836 316836 308840 304844 300852 294863 291867 
      288871 286879 285883 286886 290889 298892 308896 311897 
      312901 311906 308918 308931 307937 307943 306956 305961 
      305969 308972 314972 317974 324972 329968 332964 337956 
      344947 347943 354939 363936 366937 367945 371950 374952 
      377949 384943 389938 396936 401936 404939 408957 408967 
      408976 407980 409989 411992 417990 422988 426985 434976 
      440965 443958 444954 448948 452947 457951 461956 475976 
      482984 491990 497992 501992 504991 506990 506986 505976 
      504969 502959 496942 485914 483906 482898 482882 482862 
      482846 480827 480811 479794 478778 476764 472744 470732 
      468719 464698 
 0.01 445088 443084 438083 434080 433074 431072 433069 434064 
      434060 433058 432064 429068 424071 421075 419080 415082 
      414087 414095 415101 421103 426101 427095 426092 424087 
      424083 430082 433086 436090 438085 442089 445088 
 0.01 413137 413135 413133 411132 408133 407133 405134 402136 
      400136 402137 403140 404141 407142 410141 413138 413137 
 0.01 296813 292808 286805 281802 276801 270800 261802 260808 
      263813 268818 274821 279823 286823 293819 295817 296813 
 0.25 452712 449696 445685 442679 437673 432667 429667 425671 
      422679 419686 417697 413713 411732 408751 405759 403765 
      398775 394782 391791 387798 383804 377810 372816 365822 
      358827 350831 340837 335842 330848 327854 325860 324869 
      325880 324888 324894 323898 320906 318912 320920 321931 
      325931 334919 341911 346906 352904 355908 359913 360913 
      367908 373902 376900 380899 386903 388906 390912 392915 
      395916 399916 404915 413912 418911 420913 423919 423926 
      423934 424941 426944 432942 434939 444925 456913 461905 
      463898 466886 468876 468863 468854 466841 465831 462804 
      463782 462770 460757 458747 456737 452712 
 0.25 455240 455234 453230 453222 449218 443217 437217 428218 
      424218 420221 418225 415225 414223 413220 410222 407225 
      408232 410237 415244 421246 426247 435246 443244 452243 
      455240 
 0.25 406217 402211 397205 392201 384197 379194 373191 373194 
      377202 379208 384214 392217 398221 402221 404219 406217 
 0.25 372223 374220 372218 370219 371223 372223 
 0.50 447715 444701 439692 436687 432685 430686 427689 425695 
      424703 421720 418738 416756 414765 412772 406784 401793 
      397799 386812 382817 378822 372828 365833 337851 333857 
      330864 331879 329895 328904 328909 330911 338901 341896 
      346891 351888 356888 362890 366889 374884 379879 386876 
      393877 399883 401896 404899 408897 412895 413891 416884 
      419876 422871 426864 430861 434862 436865 437870 438879 
      439885 439892 438902 437909 438914 439914 448902 453893 
      456885 459875 459864 458843 455827 453817 451805 449794 
      449782 450773 451766 452758 452749 450729 447715 
 0.50 397211 397210 395207 394206 392205 389205 386204 384200 
      383200 381199 380200 381201 383203 384204 386205 388206 
      391208 392210 394211 396212 397211 
 1.00 441742 440735 437729 434728 432730 430750 427760 424770 
      418786 411802 410807 410813 411820 413825 416830 419831 
      426828 431820 436812 438802 439792 439770 441751 441742  
 
24HR QP VT 06/12Z
 0.01 493642 492638 490635 487631 484629 483625 481617 478609 
      474603 470601 465601 460601 454603 442606 440606 437608 
      435614 429626 425636 421641 415647 410652 407656 395668 
      391673 389679 384691 383703 385715 386721 389728 391732 
      391736 387737 382739 378739 365743 357748 347757 329774 
      323781 316790 310799 304806 300809 296809 286806 276802 
      270801 263806 261808 262813 265817 269819 286827 290830 
      293833 299845 302852 304860 305874 305880 305886 308900 
      316925 315937 319950 322956 325963 325968 324971 319976 
      313980 310984 315986 326987 340987 351988 355991 358995 
      365004 371016 374029 375034 372041 371046 372053 372057 
      371061 369065 370071 374086 377102 377105 375111 373122 
      373128 376133 379134 385132 389129 391122 397108 401103 
      406106 404110 403116 402122 405127 408130 414133 413138 
      410142 406147 402154 406159 413160 417162 421159 423154 
      424149 427132 431127 435128 437132 436140 437150 437158 
      440163 444166 448172 447176 443180 442185 443190 446193 
      451189 459178 463176 467175 471176 484180 497185 517200 
      522202 523194 527182 528173 526168 524163 520158 515152 
      509144 502134 490111 483098 482089 481085 480079 482074 
      485077 489077 492073 494065 496058 499054 505053 510057 
      512056 513052 511046 506033 505026 500019 497017 493018 
      490023 485028 482028 478025 474020 470019 466021 462026 
      459026 449022 442021 436024 432029 429031 426030 423023 
      421015 415003 409996 403986 399983 396979 391973 389967 
      386961 385951 387942 388934 387926 383910 381904 379896 
      375883 369872 363863 361856 363850 369841 377832 385822 
      393813 400805 406803 411805 414809 418820 419828 422837 
      427849 433863 441875 444880 449885 456891 459893 464894 
      467891 470886 471878 472868 473833 475820 480806 484794 
      488780 491765 493754 494739 496719 496706 495695 494688 
      493662 493652 493642 
 0.01 512271 514266 515260 515251 514242 512235 505220 502215 
      497209 493206 486204 474204 463208 453210 440214 436215 
      431218 426219 421222 417226 414232 410237 409242 411249 
      416255 426263 430265 437268 449270 456271 463274 477280 
      484283 489283 495286 499291 502291 504290 509283 512271 
 0.25 476653 475647 472642 466637 462630 459623 455621 448624 
      442629 437636 434643 427651 424657 421667 420674 420681 
      423701 420716 421722 424725 429728 434764 437772 439776 
      442781 447784 454786 459785 466781 469774 472764 477747 
      479740 481729 482713 481691 476653 
 0.25 507268 510260 511251 510245 508238 504228 497218 494216 
      488214 479213 461216 442222 436225 432229 429236 427243 
      427246 428250 431253 436256 442257 451258 469257 481260 
      489266 494270 498274 501278 504277 506272 507268 
 0.25 412026 412020 411017 407011 403004 400002 396003 392009 
      390016 388024 386034 386043 388050 391052 395053 399051 
      401048 403045 406042 411037 412028 412026 
 0.25 354805 351803 348804 346807 344811 343818 342822 341826 
      342833 345839 348841 350840 352836 352830 353824 353821 
      354814 355809 354805 
 0.25 375938 374925 371913 369903 365893 360887 355889 352893 
      352899 354911 354917 354920 349926 340931 334936 331942 
      332947 335950 340956 343966 348971 356973 363969 367966 
      369962 372955 374946 375938 
 0.25 339862 336856 334854 331849 327847 323854 319862 318873 
      318883 318894 318899 319901 322899 326892 330884 334874 
      337866 339862 
 0.50 465658 465654 464649 459646 455644 451644 446646 443644 
      441645 437651 429660 428670 430683 432689 436696 439704 
      442719 444731 444743 444749 447756 449759 453761 459762 
      462762 465758 467752 468728 468714 467707 465702 462685 
      461675 463664 465658 
 0.50 504267 506261 506254 506244 503236 497231 489227 484222 
      480220 476220 469221 460219 454223 450227 441227 439234 
      435246 439250 444250 450248 456248 465250 473251 482254 
      495265 500270 504267 
 0.50 406030 406023 405019 401015 399013 397015 395020 394024 
      392030 389035 390042 392045 395046 398045 400042 402038 
      404034 406030 
 0.50 369936 368931 364928 359930 356932 353936 352940 350947 
      351954 350957 351960 354959 358959 362959 365955 366951 
      367947 369939 369936  
 
24HR QP VT 07/12Z
 0.01 485701 482689 478676 474666 471662 466663 453664 448666 
      444669 441674 441682 445694 445701 442710 439716 437725 
      437733 437737 440743 443749 446752 449751 457737 464731 
      469723 472716 4