FXUS04 KWBC 282021
QPFPFD
 
QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
420 PM EDT WED APR 28 2004
 
PRELIM DAY 1 AND DAY 2 QPF DISCUSSION
VALID APR 30/0000 UTC THRU MAY 01/0000 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR
 
               
DAY 1...       

NRN/CNTRL ROCKIES...

MODELS REMAIN MOSTLY SIMILAR DIGGING CLOSED LOW AND EMBEDDED
VORT ENERGY SLOWLY SWD THRU THE GREAT BASIN.  JET ENERGY AND
UPPER DIVERGENCE EAST OF THE SYSTEM CONCENTRATES ACROSS UT/WY
AND PORTIONS OF CO DURING THIS PD.   ETA AND GFS BOTH CONCENTRATE
THE HVST QPF AMTS ALONG AN AXIS FROM THE UT WASATCH TO CNTRL WY. 
WITH LOW HEIGHTS SETTLING INTO THE GREAT BASIN PCPN COVERAGE
SHOULD INCREASE DURING AFTN HEATING ON THU.  PCPN EAST OF THE
MTNS SHOULD BE ENHANCED FROM INCREASINGLY STRONG LOW LEVEL ELY
UPSLOPE FLOW WHICH GENERATES HIGH UVV/RH VALUES OVER ERN WY.  
INDICATED SOME .50 INCH PLUS AMTS THRU THE FAVORED OROGRAPHIC
AREAS OF UT AND WY WHICH IS GENERALLY SUPPORTED BY THE ETA/GFS.

NRN PLAINS TO UPPER MS VALLEY...

LARGE MODEL DIFFS ARE EVIDENT WITH 12Z GFS INDICATING SWATH OF .25
INCH QPF AMTS THROUGH SD/ND AND IN NRN MN WHILE THE ETA IS MOSTLY
DRY.  THE 12Z GFS VORT EJECTING FROM WY WHICH IS GENERATING THIS
PCPN IS QUESTIONABLE AND LEANED TOWARD THE LIGHTER ETA.  SOME
LIGHT SHOWERS ARE POSSIBLE IN THE LOW LEVEL NRN PLAINS
CONVERGENCE ZONE AS NRN STREAM VORT ENERGY BRUSHES ACROSS ND.  
A BETTER THREAT FOR RAIN SEEMS TO BE THU AFTN ALONG THE BNDRY
ALIGNING DURING THU AFTN FROM IA TO SRN WI AND NRN IL AS SRN
STREAM
MOISTURE INFLOW AND POSSIBLE SHRTWV ENRGY REACHES NEWD. 

TX/SRN PLAINS...

THE GFS HAS BEEN HANDLING THE PCPN BREAKING OUT OVER CNTRL TX
BETTER THAN THE ETA AS SHRTWV SYSTEM ADVANCES ACROSS THE SRN
PLAINS TONIGHT.    MOISTURE AND LOW LEVEL FORCING ARE RATHER
MINIMAL WHICH SHOULD KEEP PCPN MOSTLY LIGHT AND DISORGANIZED. 
SOME .25 INCH PLUS AMTS ARE POSSIBLE FROM NERN TX AND ERN
OK....WITH REMNANTS OF THE UPPER SYSTEM AFFECTING MO ON THU.  

LOWER MS VALLEY...CNTRL GULF AREA...

SCT CONVECTION SHOULD DEVELOP DURING THU AS GULF INFLOW
INCREASES WITH PW VALUES SURGING TO ABOVE 1.5 INCHES IN SOME
AREAS.  MODELS SUGGEST THAT THE SRN PART OF THE TX UPPER SYSTEM
SHOULD WORK INTO LA DURING THU...WHILE WEAK EMBEDDED GULF
IMPULSE MAY LIFT NWD INTO MS/AL AND THE FL PANHANDLE.  

FL...

AXIS OF HIGH PW VALUES LIFTS NORTH ALONG WITH INCREASING SELY
FLOW.  MOST FAVORED LOCATIONS FOR CONVECTION SHOULD BE THROUGH
THE CNTRL AND WRN PART OF THE PENINSULA DURING DIURNAL HEATING.

DAY 2...

IN THE CENTRAL ROCKIES AND CENTRAL HIGH PLAINS...PCPN HERE WILL
BE IN ASSOCIATION WITH INITIALLY CLOSED UPPER LOW SWINGING
ACROSS THE AREA.  THE GFS IS FASTER THAN THE ETA WITH THIS SYSTEM.

THE UKMET AND THE CANADIAN MODELS SUPPORT THE FASTER GFS
SOLUTION.  THEREFORE HAVE LEANED TOWARDS THE HEAVIER GFS PCPN
FORECAST.   PCPN WILL BE IN THE FORM OF SNOW AT HIGHER
ELEVATIONS.

FROM THE CENTRAL PLAINS NEWD ACROSS THE MID MS VALLEY TO THE
GREAT LAKES...  PCPN... MDT TO HVY... WILL BE FALLING GENERALLY
ALONG FRONTAL ZONE.  THE GFS IS SLOWER THAN THE ETA WITH THE
SHORT WAVE TROF SWINGING ACROSS CANADA... AND IS THEREFORE
SLOWER WITH THE EWD PROGRESSION OF THE BAND OF FRONTAL PCPN. 
MOST OTHER MODELS ARE LEANING TOWARDS FASTER ETA SOLUTION. 
HOWEVER... THE GFS ENSEMBLE MEAN SUPPORTS THE GFS OPERATIONAL
FORECAST.   ALSO...  THE ACCEPTANCE OF THE FASTER GFS MOVEMENT
OF THE CLOSED LOW TO THE SOUTH IN THE CENTRAL ROCKIES SUPPORTS
THE SLOWER MOVEMENT OF THE CANADIAN SHORT WAVE TROF. 
THEREFORE... BELIEVE A COMPROMISE IS IN ORDER... AND HAVE USED
THAT IDEA IN MAKING THE PCPN FORECAST.   

IN THE NATIONS SOUTHEASTERN QUADRANT...  BOTH THE ETA AND GFS
MODELS ARE BRINGING SRN STREAM SHORT WAVE ENERGY NEWD THRU
THE REGION.   AS FAR AS PCPN IS CONCERNED...  BELIEVE THE GFS IS
BETTER IN BEING SLOWER TO TAKE BEST ZONE OF GULF MOISTURE
INFLOW EWD.  THEREFORE... FEEL GFS IDEA OF HOLDING BACK OR
REDEVELOPING LIGHT TO MDT SHOWERS IN THE CENTRAL AND WRN GULF
STATES MAKES SOME SENSE.  AS FAR AS HVY CONVECTIVE RAINS
DEVELOPING FROM ATLANTIC INFLOW... BELIEVE THE GFS IS OVERDONE IN
NRN FL.  HOWEVER... THE ETA IS PROBABLY TOO FAST TO DEVELOP HVY
RAINS IN GA FROM THE SAME LOW LEVEL FLOW. 

HEDGE/LINDNER

GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV
 
24HR QP VT 30/00Z
 0.01 503854 502842 499833 493821 486809 479800 470790 467785 
      469780 471773 473766 474754 474748 472743 465733 451723 
      448721 445721 440724 438728 431745 430753 431762 432768 
      435772 438776 437781 436785 436789 436795 437800 439804 
      441808 447818 448823 446830 441840 435849 429856 425861 
      421864 418868 414871 400882 382892 360903 355903 349902 
      341898 338894 336889 334875 330861 328854 325848 323843 
      319840 312836 303834 300833 294834 289837 287840 285849 
      283855 279860 275865 272870 271874 270881 270892 270903 
      272916 275927 280939 285947 290955 292958 289961 286962 
      281969 277977 271992 268999 267003 267008 272012 273015 
      273019 276023 280025 286027 293027 298024 304017 313010 
      326001 335994 338993 341989 355979 362974 370968 375963 
      383959 387961 388964 389974 391975 396972 404965 410962 
      413960 423952 430942 439925 445916 451912 453910 456911 
      457917 456920 455932 453944 450953 441971 435984 430993 
      427999 425006 421018 419023 415027 410027 406024 402022 
      396022 393026 391031 389035 386036 375036 370036 363043 
      358051 357054 358058 359061 359065 355066 349066 344068 
      346070 351074 353077 355083 356090 353095 346102 340107 
      341111 344115 351123 358129 365128 370128 373132 376133 
      378139 381143 385146 389149 391145 391142 390135 393131 
      397129 402131 405132 408131 410129 413129 413135 413141 
      409147 403155 403159 408160 417163 421159 424155 426152 
      427147 427139 431132 434128 438127 442136 445137 448133 
      451130 460127 466119 470110 472104 473096 470091 467090 
      464093 461093 462086 463078 463068 462062 462052 463037 
      464024 466010 468995 470986 472981 475972 480962 490941 
      499921 501913 501909 502898 503884 503870 503854 
 0.01 293811 290806 286804 278798 274794 270792 259794 250801 
      248806 248809 250812 253816 256819 265825 273828 284828 
      289826 292821 293815 293811 
 0.25 435886 432885 428887 423891 419900 416905 415913 413921 
      413926 417927 421919 424914 428907 432900 435890 435886 
 0.25 449076 449070 447066 445058 446039 444035 441034 436037 
      432040 426043 414046 404053 396058 393062 392064 392070 
      396070 398065 401067 401070 401075 403079 402090 401100 
      399105 394109 385116 384118 385122 387123 394121 399121 
      406121 414121 420119 424116 423112 421111 429109 434105 
      438104 441100 444097 444093 442087 441082 444079 449076 
 0.25 427100 427099 424096 424095 422095 422099 424102 426102 
      427100 
 0.25 400932 397930 394931 391933 389935 388935 387939 389940 
      392941 395941 398938 399936 400933 400932 
 0.25 395079 395076 392073 390076 389077 389079 389080 392081 
      395079 
 0.25 373942 371941 367941 363944 353952 346960 338967 330975 
      326981 327985 329985 333983 337980 342976 346972 352964 
      360955 370947 373942 
 0.25 379079 379075 378072 377072 375070 375072 375075 375076 
      377079 378080 379079 
 0.25 334912 327911 320910 315911 307912 304914 299916 294922 
      293932 295936 298938 304943 310944 314941 315936 315930 
      319923 328918 332916 334912 
 0.25 324881 321872 317863 311854 304848 301847 297849 295854 
      296860 298869 301878 305888 310895 315897 319898 322895 
      323891 324884 324881 
 0.25 280819 278814 276811 274806 270801 266799 263799 258801 
      255804 254807 256811 260815 263816 266818 270820 274821 
      276821 280819 
 0.25 303001 304998 302995 301995 299995 296995 293997 292999 
      291001 290002 290006 290009 292010 294011 297010 298008 
      300006 301004 302002 303001 
 0.50 436068 436063 433056 430054 424054 422057 423060 421068 
      423072 423076 421084 422088 424090 427092 430095 432092 
      430085 428080 427076 430073 434072 436068 
 0.50 410110 410106 410103 410099 409098 406098 406099 406102 
      405106 405110 404114 406114 408114 409114 410110 
 0.50 317880 317876 316873 315870 314867 312864 311863 310862 
      308859 307858 304859 304860 304864 305867 306870 307873 
      308874 309875 310878 312881 313882 316883 317880 
 0.50 270804 268803 265803 265802 262803 261804 261807 261810 
      261811 262811 265813 268812 268811 269808 269807 270804  
 
24HR QP VT 01/00Z
 0.01 499668 497659 494657 486658 480663 477667 472679 467691 
      464702 458722 452747 449760 444773 440786 435798 430809 
      425820 418840 414850 410860 405870 400879 391896 385909 
      382913 377918 374920 369921 363922 359923 357921 361913 
      366904 370895 377886 382879 386871 402857 405853 408848 
      412839 416829 419819 422809 426796 429784 431774 436745 
      433743 429746 419756 405772 391788 377802 373807 369810 
      360817 352821 345822 335821 326816 324812 323807 322799 
      320793 317789 308784 301780 296780 292781 282784 272789 
      263794 255800 249805 247809 247813 249816 254818 260821 
      277830 279832 279836 279839 278850 278863 279875 280887 
      280895 282903 284907 287910 290912 292915 294939 294951 
      292958 290963 287966 279970 269974 269980 272984 278990 
      286996 290997 297996 307993 315985 321976 330962 341946 
      346939 350932 352928 354931 353943 354953 357959 360966 
      361977 362993 361006 357030 353042 351046 350054 353065 
      355075 355082 355086 358089 361091 362097 364100 368100 
      377101 388104 389107 388110 382117 379120 377124 378127 
      382131 386134 390135 394131 405127 410122 412116 418084 
      418080 421075 428069 430064 431055 431051 429049 427045 
      426031 427018 427003 425989 424981 425973 432961 437951 
      440945 442938 450910 454900 461890 468883 474875 480864 
      485854 489845 492832 499808 503794 508777 510762 511746 
      511732 511718 509701 507690 504686 501683 497682 497679 
      499668 
 0.01 544860 543854 540853 531857 522864 515869 510876 505883 
      500892 496900 488916 484924 480934 479939 479946 484949 
      485955 483960 481971 480981 481985 485986 486009 487019 
      486028 486035 488041 489047 491051 495054 497054 502053 
      511049 518044 523039 526029 526012 525996 524989 524981 
      526971 528958 529946 528940 526937 524931 524923 522914 
      527905 532897 535890 539879 542869 544860 
 0.25 485711 483705 480709 477717 471735 467744 463755 457777 
      451793 445809 437827 428845 421860 414875 410883 405892 
      396907 387921 380933 376943 373952 372963 371975 372986 
      374998 375009 374019 371028 367039 362047 361050 360054 
      362062 364066 366069 378077 398073 404070 410064 413057 
      409050 409041 412031 414019 414009 412003 413998 414987 
      414978 417968 419961 423953 427944 431933 435924 439917 
      451884 468844 470837 472825 476808 480784 483773 486764 
      487758 486750 484742 484737 485721 485711 
 0.25 515011 515007 515002 514997 512996 511998 509000 508003 
      507005 505008 504011 504013 503017 505020 507019 510017 
      511017 513015 515011 
 0.25 401835 400831 397828 392827 388827 381828 375832 370836 
      359845 354848 347850 334854 323853 318851 313848 306841 
      303837 307834 313830 316825 318821 318814 317807 315799 
      312794 308791 303790 296789 284792 279794 273799 273802 
      275809 278814 282818 286823 290827 292832 290836 288841 
      287847 287853 287860 288868 289875 292889 299897 302903 
      304912 304921 304926 304933 306939 309942 314941 322932 
      329922 335914 341907 347902 352899 357894 360888 371870 
      375865 379861 384857 391851 396844 399839 401835 
 0.50 475752 472751 469754 468759 466763 464768 462774 460780 
      458785 457790 458792 460789 463786 465781 468775 470769 
      472763 473758 475752 
 0.50 463819 461809 459805 456807 449817 441830 434843 428855 
      424866 421872 419881 416888 412894 383936 379946 376958 
      376976 378982 379992 380000 382008 383014 383022 375035 
      369046 367052 367056 369059 373062 380063 395061 400057 
      403049 406034 406029 406021 397011 395009 395003 398997 
      401994 404989 407984 409977 409967 411958 416945 425922 
      433911 437905 441897 445885 450873 456859 461843 463831 
      463819 
 0.50 377848 375845 373846 366848 358852 353855 348859 343862 
      329864 318862 309854 305850 301848 298848 296851 293853 
      293857 293870 295879 299888 307895 311901 309909 308915 
      308922 309926 312925 315920 321911 331900 338893 342887 
      348884 354880 358877 363872 366863 371855 377848 
 0.50 313806 311802 308800 300798 292796 289795 283797 281799 
      280806 283812 290818 296823 302828 304827 309822 313816 
      313806 
 1.00 442876 442871 442867 439867 437869 436869 434873 434874 
      432878 432879 430883 430884 429888 429891 429892 429893 
      432893 435891 435890 437888 438885 439883 441880 441877 
      442876 
 1.00 405942 406938 404935 403935 401938 400940 398943 398944 
      396947 395948 394951 393953 391956 391957 392957 394957 
      397956 400955 402951 402950 405946 405942 
 1.00 398034 396031 392030 388031 383035 381039 378043 376047 
      376050 378054 381054 384053 389050 392048 395045 397038 
      398034 
 1.00 309811 308809 307808 305806 304805 301804 300803 297802 
      294802 291804 290805 289807 289809 291811 291812 294814 
      295815 296816 299818 302819 305819 307816 307815 309812 
      309811 
 1.50 303813 302811 302810 299810 296811 296813 297813 300815 
      301815 303814 303813  
 
$$