FXUS04 KWBC 302220 PAA
QPFPFD
 
QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
619 PM EDT FRI APR 30 2004
 
FINAL DAY 1...DAY 2 AND DAY 3 QPF DISCUSSION
VALID MAY 02/0000 UTC THRU MAY 04/0000 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR
 
THE 18Z MDLS WERE IN VRY GOOD AGREEMENT WITH THE 12Z MDLS..AT
LEAST
MASS FIELD-WISE..SO MADE ONLY MINOR CHGS TO THE PRELIM DAY 1 QPF.
  
     
DAY 1...       

...SRN PLAINS..MIDWEST..GT LAKES...

AMPLIFYING NRN STREAM TROF IS EXPECTED TO COMBINED WITH WEAKEN
CLOSED LOW LIFTING OUT FROM THE SRN ROCKIES TO PRODUCE AN EXPAND
AREA OF RAIN/TSTMS ALONG AN ASSOCD COLD FRONT WHICH IS EXPECTED TO
PUSH EWD INTO THE OH VALLEY AND LOWER MS VALLEY BY LATE SAT.   
INGREDIENTS SHOULD COME INTO PLAY OVERNIGHT FOR A SIGNIFICANT
CNVTV
OUTBREAK ACRS ERN PORTIONS OF THE SRN PLAINS AS ENERGY EJECTING
OUT
OF THE CNTL ROCKIES INTERACTS WITH INCREASING LOW LEVEL JET
FEEDING
INTO NE/SW ORIENTED FRONTAL BNDRY LOCATED OVER ERN PORTIONS OF THE
SRN PLAINS.   HEIGHT FALLS AND STRENGTHENING RT ENTRANCE REGION
JET
SUPPORT SHOULD PROVIDE EXHAUST FOR DVLPG TSTMS ALONG THE BNDRY
WHILE THE SLY FLOW OF INCREASING HIGH PW AIR OF GREATER THAN 1.5
INCHES PROVIDES MSTR/FUEL FOR DVLPMENT.  THE GFS AGAIN DISPLAYING
USUAL GRIDSCALE FEEDBACK PROBLEMS...BUT USUALLY WHEN THEY DISPLAY
THEM WITH DECENT DYNAMIC SUPPORT...ITS USUALLY A SIGN OF
SIGNIFICANT
RAINS SOMEWHERE IN THE VCNTY.   THERE WILL BE SOME POTNL FOR
TRAINING
WITH MEAN UPR WINDS PARALLEL TO SFC FRONT...THOUGH OVERALL TREND
OF
FRONT SHOULD BE SLOWLY PROGRESSIVE.  MAIN ADJUSTMENT WAS TO SHIFT
ETA MAX SLIGHTLY NEWD ACRS NE TX/SE OK TOWARD THE MORE CONSISTENT
GFS.   WITH SFC WAVE EXPECTED TO DVLP ALONG THE BNDRY...SOME MDT
TO
HEAVY RAINS SHOULD SPREAD NEWD ACRS PARTS OF NRN AR INTO SRN IL
AND
IN WHERE AGAIN GOOD RT ENTRANCE REGION JET SUPPORT WILL EXIST TO
SUPPORT HEAVIER RAINS.   

...SERN U.S..
AXIS OF DEEP LAYERED MSTR..PWS IN EXCESS OF 1.75 INCHES..IS
EXPECTED TO
FOCUS ALONG THE SE COAST AHEAD OF SEVERAL WEAK UPR LEVEL
DISTURBANCES AND WEAK UPR LEVEL DIFFLUENCE.   IN ADDITION..MDL
INDICATE WEAKLY CONVERGENT 85H FLOW ACRS THIS AREA WHICH COMBINED
WITH THE HI MSTR..UPR DISTURBANCES AND ANY SEABREEZE ACTIVITY
SHOULD SUPPORT SOME WIDESPREAD SHWR/TSTM ACTIVITY ACRS THIS
REGION. 
GFS ALSO SHOWING GRIDSCALE FEEDBACK PROBLEMS HERE WHICH MAY BE
PREVENTING MSTR/SHWRS FROM SPREADING FARTHER N IN THE MODEL. 
ENDED UP GOING WITH A BLEND...BUT KEEPING HIEST AMOUNTS ALONG THE
GA/SC/NC COASTAL AREAS IN AXIS DEEPEST MSTR. 

DAY 2...

MODELS ACTUALLY NOT TOO TERRIBLY DIFFERENT WITH SPEED OF THE
UPPER TROF MOVING FROM THE MIDWEST INTO THE GREAT LAKES REGION
THIS PERIOD...ALTHOUGH THE ETA IS SLIGHTLY FASTER BY FHR 60. 
DIFFERENCES WITH THE FRONT ARE MORE NOTICEABLE THOUGH.  HPC
PREFERENCE IS THE FASTER ETA SOLUTION AS THIS IS SUPPORTED BY
THE CMC/UKMET.  IN ADDITION...THE GFS QPF APPEARS SUSPECT ALONG
THE GULF COAST AND IN THE LOWER MS VALLEY DUE TO GRID-SCALE
FEEDBACK.  STILL...ABUNDANT MOISTURE AVAILABILITY AHEAD OF THE
FRONT WILL LEAD TO A WIDE AREA OF .25 TO .50 INCH AND GREATER QPF
EXTENDING INTO NRN NEW ENGLAND BY THE END OF THE PERIOD...AND
THERE SHOULD STILL BE SOME DECENT PCPN AMTS ALONG THE GULF
COAST ANYWAY EXTENDING INTO THE SOUTHEAST.

DAY 3...

MODEL DIFFERENCES BECOME MORE PRONOUNCED THIS PERIOD WITH
THE UPPER TROF MOVING THROUGH THE EAST.  THE ETA CONTINUES TO
BE MUCH MORE PROGRESSIVE WITH THIS TROF.  THIS IS SUPPORTED BY
THE 12Z UKMET WHICH IF ANYTHING IS EVEN A LITTLE FASTER THAN THE
ETA AT FHR 60 AND 72.  THUS MANUAL QPF LEANED HEAVILY TOWARD THE
ETA FOR THIS PERIOD.  EXPECT THE BULK OF THE PCPN TO CLEAR OUT OF
THE MID-ATLANTIC AND SRN NEW ENGLAND BY LATE MONDAY...THOUGH
ERN NEW ENGLAND AND THE MARITIMES WILL STILL BE SEEING LINGERING
RAIN AS THE MAIN VORT CENTER ARRIVES WITH THE UPPER TROF AXIS. 
ALSO THOUGHT THE GFS QPF WAS TOO HEAVY ALONG THE SOUTHEAST
COAST AND HERE TOO TRENDED TOWARD THE ETA.

ONLY LIGHT RAINFALL EXPECTED ALONG THE WA COAST THIS PERIOD AS
WRN RIDGE HANGS TOUGH AND HEIGHTS FALL SLOWLY WITH THE
APPROACH OF AN UPPER LOW IN THE NERN PACIFIC.

SULLIVAN/TERRY/MAUSSER

GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV
24HR QP VT 02/00Z
 0.01 515756 518749 522735 526718 528704 524687 518671 510663 
      497658 484659 473669 454692 449699 446704 439712 432717 
      417730 391743 383744 375744 366742 353745 344751 335759 
      320774 317777 312782 303790 297794 289797 274799 268800 
      261804 257807 255813 259820 261824 262829 261842 262845 
      264847 270848 275848 282846 286843 289845 290848 292861 
      293870 292877 293885 293893 293900 291909 286921 276942 
      265964 260976 258981 258991 258995 260000 264006 269010 
      275012 285015 290016 293018 294022 299026 305029 310028 
      312026 315023 317019 323022 329027 337028 345023 353019 
      364015 373015 379021 383027 382037 380046 375055 375060 
      381066 389073 394073 399061 401050 403033 403019 396013 
      395002 399988 404977 410964 417948 423933 425926 428919 
      430913 433906 436900 440895 449882 459870 464863 467855 
      474836 477830 480820 488791 492783 495779 499776 507769 
      511763 515756 
 0.01 534849 533844 531841 528838 525838 522841 517853 512865 
      507872 499882 498890 499894 501898 505901 508901 516896 
      522891 524887 528876 532862 534849 
 0.01 519269 519264 516257 510249 507246 504246 500247 495247 
      492248 487251 483254 479257 477261 477266 478273 484282 
      488286 494288 503289 508288 512285 514281 518273 519269 
 0.25 481781 501748 515718 518707 518695 514689 505687 496689 
      484694 468715 454736 451740 444745 439749 434755 423773 
      410791 406796 407802 413813 425812 423818 421822 416826 
      410827 402829 395834 388844 375861 372866 366871 363873 
      359874 357873 353872 350872 342876 330882 322888 315894 
      311905 312909 311917 308927 301943 297952 292959 286966 
      280973 274983 274986 276989 280991 286994 290996 292000 
      300007 305013 308013 312011 319004 327998 339994 347990 
      353984 359976 363965 366956 371946 382926 386918 392910 
      397902 406900 420911 424905 427897 430886 429880 431875 
      436865 438860 440856 446847 457824 470801 474793 481781 
 0.25 378798 370799 364798 361794 363790 367784 368780 368774 
      366769 364766 353757 341767 327777 307798 300804 294809 
      285811 279812 273816 272819 273823 278833 291835 295837 
      296839 298843 301848 305855 307864 307870 315867 321863 
      325858 334846 347837 357825 367813 377801 378798 
 0.50 488750 505719 507708 502704 495708 488715 472736 469742 
      466747 463754 462761 459767 462774 466775 469774 475768 
      479763 488750 
 0.50 462797 462793 459789 457787 454788 452794 449799 448804 
      446809 445814 443820 440826 443828 445827 448825 450822 
      453818 455814 456808 458803 462797 
 0.50 426840 419843 414846 410846 405845 399843 395845 387856 
      380868 378871 373876 365885 355893 349898 345899 348890 
      349884 347881 344883 335893 327903 322913 317923 312934 
      308947 305952 302955 295963 288971 283976 280981 282985 
      288985 295984 300982 303981 305982 303988 305003 308008 
      312005 318996 323992 329990 337987 342984 349978 353974 
      356970 362956 368944 373934 378923 385911 399890 407880 
      414869 419862 421854 426840 
 0.50 359773 358770 356769 353768 347769 341773 334776 330780 
      324787 309803 301810 292815 286819 284822 283828 287829 
      295831 303834 311841 315843 320843 325839 328835 334829 
      342821 348812 349799 349794 352789 358781 359773 
 1.00 359952 367934 378911 387896 391886 393880 393876 391873 
      386875 373884 363893 354902 347912 346916 347920 352925 
      347931 344936 339948 325969 319978 317984 320985 323985 
      331982 336980 346972 354963 359952 
 1.00 349782 345781 342782 338783 332787 324795 316805 309814 
      302821 306823 310826 315827 318826 321824 327816 334806 
      336800 339796 346787 349782 
 1.50 379893 381888 377886 372889 368892 365896 362899 359902 
      355907 353910 351911 352915 356915 362913 365911 370907 
      372904 374901 377897 379893 
 1.50 354956 357948 358943 359939 360936 360933 357931 355931 
      348941 346942 342950 337957 331964 325972 323975 328978 
      331979 334977 341972 349965 354956 
 2.00 352957 353953 353950 350945 346948 343952 340956 338960 
      335963 332966 332971 336972 341969 344967 346964 349961 
      352957  
 
24HR QP VT 03/00Z
 0.01 519668 519676 516684 511701 506720 503730 499737 494749 
      489757 481773 477782 473790 465807 459820 452832 443849 
      435861 425874 418880 417883 419886 426889 434889 443890 
      450893 459898 475904 483919 489939 496967 495987 486986 
      477982 471978 467974 460972 456975 456979 457985 454987 
      449986 446983 441979 428973 423969 416961 412953 410949 
      406949 397951 390948 381940 376936 372931 372923 375916 
      375910 372908 367908 363910 358914 354918 343932 333945 
      329950 326956 323962 321969 319975 316980 308990 299001 
      290009 283012 274014 268012 261009 256006 251002 247996 
      245989 245982 245977 247963 252949 254943 254937 255917 
      256902 259889 263876 266866 270853 272845 270839 266833 
      264829 258821 255817 254812 254807 259804 267803 278803 
      291802 302800 309797 314794 320789 324783 328777 330769 
      333762 339755 344750 349746 354745 367742 383736 395732 
      403719 418709 425706 432701 440693 446685 451678 456670 
      461662 468654 483638 489633 494630 500630 505632 
 0.01 540197 537187 532175 526166 517158 509156 500155 497161 
      496170 499186 499198 496203 494203 484200 481199 479203 
      479208 483217 486228 483230 478228 474229 470236 471243 
      473248 477261 482268 490275 499283 506292 511296 
 0.25 509664 506657 503653 499652 495654 489659 484666 477674 
      468687 459699 451708 441718 425732 403748 400751 395758 
      390767 386769 383768 379765 375762 371761 363761 357763 
      353767 341783 333793 326800 316808 306814 297818 289819 
      283820 280824 281830 283832 287836 289839 290843 290848 
      289854 282874 279889 273908 270919 270929 269940 266951 
      259965 257974 257978 259981 261984 270989 276990 281988 
      289983 294977 311944 315936 319930 321927 328926 333923 
      339913 345896 350888 356881 365873 372870 377869 389867 
      393865 399861 405855 412847 419839 425830 431819 438810 
      445799 454788 460781 465772 477751 483738 488728 493717 
      497707 501692 504682 508672 509664 
 0.25 511260 511258 511256 509251 509250 507247 504246 502247 
      501250 500251 498255 497259 498264 498265 501268 503271 
      506272 509269 510265 511261 511260 
 0.50 485719 491698 496684 502671 501661 496662 488674 477694 
      469706 460719 450727 441729 430735 419745 409753 409759 
      416765 429766 439760 449757 455760 464754 474740 485719 
 0.50 368857 378847 389834 402827 406822 405817 397818 390818 
      378817 372810 365802 360797 353793 341801 331809 322816 
      310824 302826 297826 291827 293830 297831 300833 304838 
      302851 300857 297863 291874 288883 285894 281906 280919 
      279930 277944 275956 271967 270971 271974 274977 281978 
      287975 291971 293965 298953 307933 312923 319913 334896 
      342886 349876 357868 368857 
 1.00 355860 356856 354853 352853 350854 348856 347856 345858 
      343861 344864 347867 347866 349866 352863 354861 355860 
 1.00 310905 319891 323881 321876 308879 300889 296899 292906 
      290914 291920 289930 288940 288946 292946 294941 296935 
      297928 299922 302916 310905  
 
24HR QP VT 04/00Z
 0.01 511645 512656 511667 511675 510681 508686 505694 499704 
      494715 492721 487728 480736 475741 470744 462749 450756 
      440763 422777 413785 403794 391807 386815 382823 373844 
      369852 363861 360866 354873 347881 344884 339886 334888 
      329887 325884 321883 316883 313885 311888 306896 302901 
      296909 291914 288916 285917 281914 279909 277904 272902 
      269900 264895 260884 260876 262866 264859 270842 273833 
      274829 272825 267820 266815 262809 262804 264800 266799 
      276795 286793 298788 304781 310774 315768 322760 328755 
      337747 345739 357724 369709 383695 417659 424651 430644 
      450626 460618 470613 475612 479612 487615 490619 491624 
      501622 
 0.01 544188 541180 537168 526148 517129 506109 496095 487087 
      480083 471081 464081 456085 451097 449107 448114 448121 
      451126 456127 463126 468126 472128 479133 483138 486143 
      490153 493162 494168 495174 499187 503196 500200 498200 
      492198 490196 487194 484195 481200 474207 468210 462216 
      458227 457232 457236 457240 459245 462249 470256 475260 
      478264 485271 495283 500289 501292 506296 510298 
 0.01 531867 528864 521867 516872 511876 505883 496897 488911 
      485921 483931 482945 485958 488960 492957 494954 503939 
      511923 518907 525890 527883 529875 531867 
 0.01 413898 410889 407884 404881 399878 393879 390878 388873 
      387866 384861 382858 376856 371857 370862 373873 373879 
      371884 368889 365897 362906 362916 362921 364926 370932 
      375935 381935 385932 395920 408909 412902 413898 
 0.25 474639 472636 469637 464639 456645 449652 437667 424682 
      413692 401705 390719 383726 378731 371737 365739 357741 
      354743 351746 346752 342758 333771 325782 319788 315792 
      307798 299802 286807 283812 283816 292824 291831 287837 
      284844 282851 282863 282873 284882 286888 288890 290889 
      296883 303874 307869 313865 323857 336845 339837 342832 
      352823 361812 371800 382787 391776 402763 425736 433725 
      438717 444711 451703 459695 471683 473671 472661 474649 
      474639 
 0.25 523261 522256 519249 514241 506231 498223 496221 492221 
      487233 485237 479239 477243 480247 485255 490266 496276 
      498279 504285 506287 512290 
 0.50 514281 516278 518273 515263 507254 501252 497253 494256 
      493259 495264 498269 500275 505280 510282 514281 
 0.50 420704 411705 406708 399717 387734 381742 373750 367754 
      364752 361749 359749 355749 352752 345760 340769 333779 
      325790 320796 312804 306808 300808 295809 290810 288813 
      293815 298815 302816 303821 297830 291841 289849 288855 
      289861 292867 296869 299867 308