FXUS04 KWBC 010722
QPFPFD
 
QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
321 AM EDT SAT MAY 01 2004
 
PRELIM DAY 1 AND DAY 2 QPF DISCUSSION
VALID MAY 02/1200 UTC THRU MAY 03/1200 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...       

...MID-LOWER MS VALLEY-LOWER OH VALLEY/SOUTHEAST TX...

FAVORABLE UPR JET DYNAMICS PERSIST ACRS THESE AREAS AS ELONGATED
RIGHT ENTRANCE REGION TO UPPER LEVEL JET INTENSIFYING TO 130 KT
OVER
THE GRT LAKES PROVIDES DIVERGENCE ALOFT ACRS ALL OF THE MID-LOWER
MS VALLEY/SOUTHEAST TX.  GFS INDICATES STRIPE OF 1.5-1.75 INCH
PRECIPITABLE WATER VALUES FM AR-TN SOUTH TO LOWER TX AND LA-
MS...WITH EMBEDDED 2 INCH MAXIMA. LOWEST BEST LIFTED INDICES OF -3
TO -5
ARE FCST BY BOTH THE ETA AND GFS OVER COASTAL TX. 

THE 00Z GFS SHOWED LIKELY GRID SCALE PROBS AGAIN OVER LOWER
TX...WITH
TOTAL AMOUNTS SEVEN TO EIGHT TIMES THE CONVECTIVE COMPONENT OF GFS
PRECIPITATION.  THE PROGRESSIVE NATURE OF FRONT SHD PRECLUDE 4-7
INCH
AMTS OVER SOUTHEAST TX AS THE GFS LOW LEVEL INFLOW AND PW AXIS
MOVE ACRS TX INTO LA AND THE GULF OF MEXICO.  ETA AMTS OVER MOST
OF
THE THREAT AREA APPEAR UNDERDONE GIVEN FAVORABLE COMBINATION OF
MOISTURE/LIFT/INSTABILITY COMING TOGETHER OVER THREAT AREAS PLUS
CONTINUITY FROM ONGOING CONVECTION ACRS MO-AR-TX.  AREA WIDE ONE
TO TWO INCH AMTS ARE FCST AND WHERE TRAINING OCCURS LOCAL THREE TO
FOUR INCH AMTS ARE POSSIBLE.

CONVECTION HAS AGAIN DEVELOPED EARLY OVER SOUTH LA AND
APPROACHING FRONT AND HIGH PW/MOISTURE CONVERGENCE AXIS WILL ONLY
CONTINUE THREAT OF SHOWERS/STORMS...SO THREAT AREA WAS EXTENDED
FURTHER EAST ACRS SOUTHEAST LA WHERE FF GUIDANCE VALUES WERE 1-1.5
INCHES DUE TO YESTERDAY'S RAINS.

...SOUTHEAST/ FL..
AXIS OF DEEP LAYERED MSTR..PWS NEAR 1.75 INCHES..IS EXPECTED TO
FOCUS
OVER EAST SC/NC AHEAD OF WEAK LOW LEVEL DISTURBANCES AND
PERSISTENT UPR LEVEL DIFFLUENCE.   THE ETA QPF MAXIMA OVER SC-ADJ
NC
APPEARS OVERLY FOCUSED GIVEN PROGRESSIVE NATURE OF ONGOING
ACTIVITY AND PROGRESSIVE FCST OF WEAK SHRTWVS IN MULTIPLE LEVELS
OF
THE ATMOSPHERE.  MANUAL QPF LEANED MORE TWRDS GFS AS GFS HAS A
BETTER HANDLE ON ONGOING ACTIVITY MOVG INTO SC FURTHER NORTH THAN
ETA FCST...PLUS GFS HAS SUPPORT FROM CANADIAN GLOBAL AND UKMET
MODELS WITH FCST OF HIGHER AMTS IN EAST NC. 

THE GFS ALSO FCSTS HIGHER AMTS OVER NORTHERN PENINSULA OF FL.  THE
GFS IS FAVORED HERE TOO AS THE ETA SUPPORTS GREATER CVG AMOUNTS
THROUGH ITS FCST OF 1000-500 MB RH OF 70-90 PERCENT PLUS DIURNAL
INSTABILITY AND SEA BREEZE BOUNDARIES TO PROVIDE ASCENT.

DAY 2...
THE ERN CONUS IS THE FOCUS OF QPF DURG THE DAY 2 PD.  ALL MDLS
MOV H5 TROF EWD AS A SFC LOW MOVS FROM NT NY STATE INTO SRN
CAN. MDL DIFFS ARE APPARENT ERLY ON.  THE GFS IS MORE AMPLIFIED
THAN THE ETA WITH ITS H5 TROF.  THE CAN IS VERY SUPPORTIVE OF THE
GFS.  THE UKMET CONTINUES TO BE FASTEST AND WKST WITH THIS SYS
AND IS THE OUTLIER...BY FAR...WITH ITS SOLN.  THE ETA AND GFS HAVE
ALSO TRENDED SLOWER THAN THEIR PREV RUNS WITH THE UPR TROF AND
SFC LOW/CDFNT IN THE ERN CONUS.

THERE IS VERY STRONG UVV FCST ACRS THE MID ATLC WITH THIS SYS
AND STRONG DYNAMICS...WITH UPR JET ENERGY AOA 130 KTS FROM THE
SERN CONUS INTO SRN CAN.  STRONG LLJ...AOA 30 KTS...FROM THE SW
WILL KEEP ABUNDANT MOISTURE OVER THE AREA.  PWS ARE AOA 1.50
INCHES ALG THE ERN SEABOARD.  ECMWF...CAN...AND TO A LESSER
EXTENT THE GFS AND ETA FCST SEVERAL SFC WAVES TO MOV NWD ALG
THE SLOW MOVG CDFNT.  CONFIDENCE IS LOW WITH RESPECT TO THE
TIMING...STRENGTH AND LOCATION OF ANY OF THESE WAVES. 
HOWEVER...THEY WILL HELP TO ENHANCE ANY QPF WITH SHWRS/TSTMS IN
THEIR PATH.  

MAN PROGS FAVORED THE GFS/CAN SOLNS WITH SOME MODIFICATIONS. 
THESE SOLNS SUPPORT THE SLOWER TIMING OF THE TROF AND SFC
CDFNT.  IF THESE TRENDS CONTINUE...EXPECT AN EVEN SLOWER MOTION
NEXT CYCLE.  OF COURSE...TIMING DIFFS WILL AFFECT WHAT PD PRECIP
FALLS IN FOR A GIVEN AREA.  DESPITE THE MDL MASS FIELD
DIFFS...OVERALL QPF PATN OF GFS/CAN AND ETA ARE SIMILAR AND WERE
GENLY FOLLOWED.
                    
ELSEWHERE...ACRS THE MID-MS VLY...SOME LIGHT PRECIP IS EXPECTED
AS TROF PASSES THRU THE AREA AND SEVERAL S/WVS SWING THRU. 
THERE IS SOME DECENT UVV...BUT MOISTURE IS LACKING AND QPF WILL
BE LIGHT.

ACRS THE PAC NW...GENLY LIGHT QPF AS S/WVS MOV INTO SRN CAN
AHEAD OF UPR LOW IN THE N PAC.  

PETERSEN/NIERENBERG

GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV
 
24HR QP VT 02/12Z
 0.01 530705 528697 526691 521677 518671 515669 511668 508664 
      495651 487656 482660 477662 472667 467674 460681 457688 
      446703 439710 431717 418729 413730 409730 403728 394726 
      385728 378730 374732 369733 357737 352738 346743 341749 
      334756 323766 319772 314778 306784 296787 287790 277794 
      260799 259802 256804 252809 252813 255817 260824 264829 
      266834 270843 271847 271852 269866 269869 267871 265869 
      259866 254863 248862 259870 263873 266875 268879 268887 
      267896 262923 260929 257934 247946 242958 236973 234980 
      235982 238984 247992 248999 247004 261008 265012 272014 
      280015 288016 299015 303013 305010 313000 318993 321986 
      328975 335964 351959 366954 371953 375949 380942 392928 
      401916 408911 413913 418917 420921 420928 415958 419965 
      424970 431975 439978 446983 450986 454987 457984 456978 
      456975 458973 464973 476981 482984 490988 495987 496982 
      496976 495967 493955 490943 486935 484923 482915 479910 
      476906 473904 466901 450897 424891 422891 421886 427880 
      433874 439867 461838 469831 473823 480804 484794 488786 
      495779 502773 509768 511764 515759 517752 519740 524731 
      528723 530705 
 0.01 525256 523248 520240 515228 511222 506216 501211 498209 
      494209 489214 488218 487224 487229 485232 483230 479228 
      476228 473233 472240 474248 475256 476265 478272 481277 
      485283 491287 499289 503289 512288 
 0.25 519703 516694 512688 507687 503688 499691 473705 466710 
      460715 450724 440734 435737 430741 421752 409762 404767 
      403774 401783 399786 396789 377800 374801 372804 371810 
      367814 364817 360815 360810 369800 370794 374789 380783 
      384776 388766 388757 385753 382750 374746 365747 352751 
      344756 339761 332770 324783 318791 310800 306803 299807 
      294809 287810 283810 276812 274814 273817 274824 280835 
      283841 286849 288856 288862 283873 279881 276892 274902 
      271914 268925 267933 265940 252979 253987 255991 259994 
      265997 277001 288004 295003 299001 306992 316974 321966 
      329955 337946 341942 348938 372928 380922 388913 396905 
      400900 404894 419871 426860 430850 437839 449830 456821 
      466808 480780 490756 507730 516716 519708 519703 
 0.25 507263 505259 502258 499260 501265 504266 507263 
 0.50 500719 496719 493722 486727 473732 464739 460745 458753 
      454758 436780 417799 406805 398809 391814 387818 380821 
      374822 366826 362829 356832 343840 340844 335848 326853 
      321855 318848 320843 324838 332833 338830 342835 344831 
      343817 346810 349805 358797 364789 371778 375772 378765 
      378762 377758 374753 370752 367752 360752 355754 349757 
      345762 341767 327787 313807 306812 299814 286816 281819 
      281824 282828 285832 289836 296840 301842 303844 304846 
      303852 302858 295867 290871 288875 284882 282888 279898 
      276912 275921 272933 257980 259986 262989 265991 271992 
      282994 289993 293992 301984 308975 315964 323953 330944 
      337937 345930 355924 369918 379911 385907 389902 394896 
      397890 407880 413870 420859 425849 427843 430838 435832 
      442827 447821 453815 458808 461803 464797 466790 472776 
      478764 483751 488743 494734 500719 
 0.50 438753 437751 434754 434755 435755 438755 438753 
 1.00 444806 443806 441804 440803 436803 433804 432804 430804 
      428806 426811 426815 428819 431819 434817 437815 439813 
      440812 442811 444808 444806 
 1.00 415829 414825 412822 408822 405825 401831 398833 393838 
      392843 391847 392850 394851 399849 401846 406842 409839 
      412837 413833 415829 
 1.00 365770 364765 362762 359761 355762 351767 347772 342778 
      338784 335791 335793 338793 346789 354785 359780 363775 
      365770 
 1.00 386883 386876 383869 379867 378863 380854 375845 373843 
      367842 357848 349853 342858 333864 325866 314870 305872 
      291885 288892 285900 283904 283909 284915 287919 290922 
      289925 285932 279938 275946 271953 268962 271965 271969 
      269973 268978 272980 275979 278977 283978 289977 298971 
      304966 309960 321945 331933 337925 341916 343913 348910 
      353908 358908 364907 369904 373902 377897 382891 386883 
 1.50 372895 370892 367894 365896 364897 363901 362901 363901 
      366901 368900 368899 371897 372895 
 1.50 330924 323920 319918 314918 308920 306923 302932 299940 
      296950 297955 298959 301961 305959 308955 313948 318942 
      323935 329927 330924  
 
24HR QP VT 03/12Z
 0.01 522684 518675 512664 507658 501655 489651 485650 478649 
      466651 451657 441662 427675 423682 418687 409702 401715 
      390725 378734 370738 361742 337755 329760 324766 318771 
      313776 302786 295794 288803 279810 268821 264825 261830 
      254842 254845 253848 251854 250860 251869 252876 252881 
      251895 252901 254907 259918 265929 274940 276942 280942 
      284938 300921 307912 315901 323891 326887 333883 339880 
      346875 352871 357866 359866 362870 364876 365882 363889 
      356899 354905 354914 356925 356933 355941 357946 363948 
      371948 386948 391950 397954 402956 408958 417958 419955 
      418949 417944 418938 422933 429932 433936 438942 441946 
      447949 450948 452944 453933 452925 451919 446914 441907 
      436902 429890 424887 419885 408875 396874 391869 388866 
      387862 383852 384847 385845 392840 400838 407836 413835 
      419835 425837 431839 437843 441846 447849 452850 458848 
      461844 465841 473837 482833 487827 497818 504811 510804 
      516799 521791 522782 523777 526777 532773 533764 532746 
      530735 530729 528719 526710 525694 522684 
 0.01 522268 522254 522249 519244 518235 515228 512223 514223 
      519227 527231 531230 534225 535222 537215 540207 540197 
      538186 536177 533170 529165 524164 517163 510159 506156 
      502155 498156 494158 493167 492177 494182 496186 500191 
      503201 506210 505210 501206 497204 489206 484203 480204 
      476211 476216 480220 484222 480240 483249 486255 490263 
      491272 493282 494287 496291 501293 505292 511289 516281 
      520274 
 0.25 519693 516684 514681 509676 506675 498674 491677 484682 
      476686 459695 439710 422722 412727 403734 394738 386743 
      352756 346761 338767 334769 330773 326779 322787 316794 
      302803 296808 292814 283825 280829 279833 277842 277850 
      279859 270870 267876 265885 267891 270894 274901 277910 
      281916 286913 292906 301897 320871 331860 338855 346849 
      353846 358843 363840 374828 380823 387817 400805 405801 
      410799 420798 435796 443795 451796 458798 464800 468803 
      473802 478798 480795 491779 496771 502763 507753 511743 
      515729 517716 519702 519693 
 0.25 529209 529204 528199 526194 523189 521183 518179 515176 
      510172 508174 507179 508188 510194 513199 516205 518208 
      521212 525212 529209 
 0.25 515272 517261 515252 511243 507235 504228 502223 499221 
      496224 496231 498241 501249 501254 499258 498262 498265 
      503274 507281 511280 514276 515272 
 0.50 514691 509685 505684 502685 486698 477703 471706 466711 
      458718 448724 441727 425734 410740 394747 378755 368758 
      363759 354761 350763 343768 335774 332781 331788 326795 
      321799 313804 306808 296819 290825 288831 288835 289840 
      292845 291851 288858 282871 278877 277880 279884 284886 
      287886 290884 300876 312866 324855 329851 336846 350837 
      361828 370822 376817 389806 400795 415784 422778 431772 
      439768 447765 455763 459762 462764 472777 476778 481775 
      485771 487767 491759 497751 506735 512726 513718 515702 
      514691 
 0.50 510269 510267 510265 510260 508259 506263 507267 509269 
      510269 
 1.00 507708 506707 504709 503712 505712 507709 507708 
 1.00 495733 494729 494728 491729 488731 485733 483736 483737 
      482742 482743 481748 483751 484755 486756 487754 488751 
      490747 492743 494739 495733 495733 
 1.00 417757 416757 413755 410756 407756 404757 401759 399761 
      397764 396765 395769 395770 399771 400771 402772 405771 
      408769 410766 412764 414761 417758 417757 
 1.00 410778 407776 404777 402779 399782 397784 394786 397786 
      400786 403784 406783 408780 410778 
 1.00 370787 370786 367785 366784 363784 360785 358787 355789 
      353790 350792 350793 348796 347798 349798 350800 353801 
      354802 357803 360803 362802 365800 367797 368795 369794 
      370791 370787 370787  
 
$$