FXUS04 KWBC 191930 QPFPFD QUANTITATIVE PRECIPITATION FORECAST DISCUSSION NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD 230 PM EST FRI NOV 19 2004 PRELIM DAY 1 QPF DISCUSSION VALID NOV 20/0000 UTC THRU NOV 21/0000 UTC REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR ...DAY 1... THERE IS FAIRLY GOOD AGRMNT AMONG THE ETA AND GFS DURG DAY 1 ACRS THE LOWER 48. MODELS CONT TO TREND TOWARD TROF AMPLIFICATION OVR THE GTBASIN...DOWNSTREAM OF THE CLOSED UPR HIGH OVR THE NERN PAC. DOWNSTREAM OF THIS...BROAD MID LEVEL SWLY FLOW WL DOMINATE MOST OF THE CNTRL TO ERN U.S. THERE ARE TWO MAIN AREAS OF PCPN CONCERN IN THE BROAD SWLY MID LEVEL FLOW ACRS THE CNTRL TO ERN U.S. THE FIRST IS WITH THE BROAD AREA OF ISENTROPIC LIFT OCCURRING TO THE NORTH OF THE W-E ORIENTED FRONTAL BNDRY STRETCHING FROM THE UPR MS VALLEY...EWD TO THE S OF THE LOWER LAKES AND INTO THE NRN MID ATL. THERE ARE NO SGFNT DIFFS WITH THE EVOLUTION OF THIS AREA OF OVERRUNNING PCPN. BOTH THE ETA AND GFS ARE SHOWING A STEADY NWD MOVEMENT OF THIS PCPN AREA ACRS THE UPR MS VALLEY/GTLKS REGION TONIGHT/EARLY SAT AND INTO SRN ONTARIO DURG SAT...WHILE THE ERN PORTION OF THE PCPN SHIELD PUSHES EWD INTO THE MID ATL/NY AND TOWARD SRN NEW ENGLAND. THE MANUAL DAY 1 QPF DID NOT DEVIATE FROM THE LGT TO MDT PCPN AMTS OF .25- .50" DEPICTED ACRS THESE AREAS. ERN TX/CNTRL GULF COAST... LOW LEVEL MOISTURE IS EXPECTED TO RETURN RAPIDLY ACRS S AND ERN TX TONIGHT AND SPREAD ENEWD INTO THE CNTRL GULF COAST AHEAD OF UPSTREAM AMPLIFYING TROF OVR THE GTBASIN AND SRN STREAM SHRTWVS AHEAD OF THIS AMPLIFYING TROF. THE ETA...CMC GEN AND GFS ARE ALL SIGNALING POTENTIAL FOR ACTIVE CONVECTION ALONG THE ASSOC FRONTAL BNDRY..PRESENTLY STRETCHING FROM S TX EWD INTO THE NWRN GULF...THAT IS EXPECTED TO LIFT BACK TOWARD THE WRN TO CNTLR GULF COAST. THE GFS' APPEARS TO HAVE SOME GRID SCALE CONVECTION PROBLEMS OVR LA AND SRN MS SAT AFTERNOON. HOWEVER...ITS MAX PCPN IS VERY SIMILAR TO THE ETA. IN ADDITION...THE GFS IS TYPICALLY VERY GOOD IN ADVERTISING SGFNT CONVECTIVE PCPN EVENTS ACRS THE GULF COAST IN THIS TYPE OF FLOW REGIME. SUBSEQUENTLY...WE LEANED MORE TOWARD THE GFS AMTS AND ITS FARTHER SWWD AXIS OF HVY RAIN COMPARED TO THE ETA. RAINFALL AMTS OF 1-3"+ POSSIBLE FROM ERN TX ENEWD INTO CNTRL/SRN LA AND SRN MS. NRN/CNTRL ROCKIES/GTBASIN... WHILE LATEST RADAR IS SHOWING LITTLE IN THE WAY OF SGFNT PCPN IN THE BROAD WRN TROF...UVVS WL BE STRENGTHENING SGFNTLY BEGINNING OVERNIGHT AND CONT INTO SAT ACRS ERN PORTIONS OF THE GTBASIN...EWD ACRS THE CNTRL ROCKIES AND OUT INTO THE CNTRL HIGH PLAINS. THE COMBINATION OF STRONG SYNOPTIC SCALE LIFT AHEAD OF THE AMPLIFYING CLOSED LOW OVR THE GTBASIN AND ENHANCEMENT TO THESE UVVS FROM POST FRONTAL UPSLOPE FLOW...WL SUPPORT A GOOD CHANCE OF WIDESPREAD WINTRY WEATHER OVR THE ERN GTBASIN...EWD INTO THE CNTRL ROCKIES AND THE CNTRL HIGH PLAINS. THIS EVENT WILL CONT INTO DAY 2 WHEN PCPN AMTS WL ALSO LIKELY BE HEAVY. ORAVEC GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV 24HR QP VT 21/00Z 0.00 477986 476946 493924 498900 497849 504791 505747 0.01 410915 411921 416930 422936 444945 466949 470956 496998 521991 537932 540868 525814 466752 461748 455742 448736 440731 432726 426721 419717 414717 410718 401719 394722 385726 356753 342781 333799 284842 267890 247958 243970 249981 257996 264001 273004 285002 292996 302994 309987 313986 318987 326990 336001 339004 342010 346020 346026 345031 342043 342052 344057 347061 352064 355066 360068 361072 359077 357082 356090 356098 353103 350107 346109 342120 345129 348131 353132 360130 368132 374135 380134 387130 396124 402123 407125 411127 418129 425129 428126 435120 440119 442126 440134 437139 436147 436157 439163 442167 456169 473158 478154 483147 485137 483130 481125 480117 478102 476096 473092 456076 452072 447069 439063 432056 428048 422038 417028 410016 406012 402010 399008 396005 390999 384991 380981 378974 375967 368961 359958 350954 346951 343947 341940 341933 341928 343922 345915 347909 347903 346894 344884 342876 340869 338866 336860 335855 339855 345859 353861 358861 365859 376856 386856 395857 402858 407860 410862 413866 413872 411878 411892 407905 407911 410915 0.01 509279 508269 505262 500253 495245 490238 489237 485236 477230 474235 472241 474250 478260 482267 487274 493279 501284 505284 507281 509279 0.25 437885 441914 449925 471930 492924 506897 503869 485826 465792 433750 407752 393764 384787 386804 397807 408809 415817 429840 433852 436868 437885 0.25 416064 416059 415055 412047 407042 400038 395038 389039 383043 378049 377052 377057 378061 381062 385062 389065 393068 401069 410068 415065 416064 0.25 329886 328878 324873 319871 313871 306872 303877 299888 297894 296900 293913 289925 283937 272956 267966 265971 264976 266980 269984 274987 279989 287989 294987 299983 305975 312964 317953 320939 323925 326913 328900 329886 0.25 312841 310838 304837 299839 294843 292845 289849 287853 287856 289859 293860 296862 302861 305856 307852 310848 311844 312841 0.50 474876 474867 473859 471851 469843 467839 463835 456830 450831 447835 447848 450864 451872 452880 453888 455896 457901 460902 463901 468897 471891 474881 474876 0.50 323905 324898 322890 319885 316883 310884 307887 301894 299899 298905 296915 289935 285943 280952 275960 271969 270974 273979 281982 287982 292980 299973 305966 310958 314949 316937 318926 321916 323905 1.00 316900 316898 312897 305903 302908 300918 296931 293940 290947 284960 280967 279969 280973 284974 289972 294967 299961 303956 310941 314924 316907 316900 1.50 312921 312915 311908 306908 304912 303917 302920 301927 301930 300937 300940 301946 303946 305942 307939 309935 310930 311925 312921 2.00 310922 310918 310915 308912 307912 307913 306916 305917 305920 304923 304925 304926 304930 305930 308932 308929 309925 310922 $$