FXUS04 KWBC 180753 PAA QPFPFD QUANTITATIVE PRECIPITATION FORECAST DISCUSSION NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD 353 AM EDT SUN JUL 18 2004 PRELIM DAY 1 AND DAY 2 QPF DISCUSSION VALID JUL 19/1200 UTC THRU JUL 20/1200 UTC REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR DAY 1... ANOTHER DAY OF VERY AMPLIFIED UPR FLOW ACRS THE NATION...WITH A CLOSED LOW OFF THE PAC NW...AN AMPLIFIED MONSOON RIDGE THRU THE ROCKIES AND A UNSEASONABLY DEEP CLOSED LOW OVR THE UPR OH VALLEY/NRN MID ATL. MID ATL/SERN NEW ENGLAND... HVY PCPN EVENT TO CONT TO DEVELOP THIS MORNING OVR THE MID ATL AS SFC LOW PRESSURE MOVES SLOWLY NEWD FROM NC TODAY AND ALONG THE MID ATL COAST TONIGHT INTO EARLY MON ON THE ERN SIDE OF THE UNSEASONABLY STRONG CLOSED LOW OVR THE UPR OH VALLEY/NRN MID ATL. THE LOW LEVEL SELY TO ELY FLOW WL STRENGTHEN TODAY AHEAD OF THIS SFC LOW...BECOMING VERY ANOMALOUS FOR JULY ACRS THE MID ATL INTO SERN NEW ENGLAND. THIS WL SUPPORT HEAVY RAINFALL AMTS ACRS MD..NRN VA...MOST OF PA AND INTO SRN NEW YORK AND SERN NEW ENGLAND. MAX PCPN DEPICTED ALONG COASTAL SECTIONS OF THE MID ATL FROM THE DELMARVA INTO SRN NEW JERSEY...L.I. AND SERN NEW ENGLAND WHERE THE ETA AND GFS BOTH SHOW MAX BNDRY LAYER CONVERGENCE. TRAINING OF CELLS HAS ALREADY OCCURRED ACRS PORTIONS OF THE DELMARVA...WITH THIS POTENTIAL CONTINUING INTO SUN IN THE AREAS OF STRONGEST LOW LEVEL SELY INFLOW AND MAX BNDRY LAYER CONVERGENCE. .50-1.5" AREAL AVG AMTS DEPICTED ACRS THE MID ATL...WITH THE HIGHER END AMOUNTS ALONG THE COASTAL SECTIONS. IN AREAS OF TRAINING...PCPN AMTS OF 2-3"+ ARE POSSIBLE. SRN MID ATL... THE ASSOC SFC CDFNT FROM THE LOW MOVG NEWD THRU THE MID ATL WL MOVE ONLY SLOWLY EWD THRU THE SRN MID ATL SUN. COLD TEMPS ALOFT WITH THE ERN TROF SHOULD HELP TO MAKE THE ATMOSPHERE VERY UNSTABLE SUN AFTERNOON/EARLY EVENING THRU THE CNTRL/ERN CAROLINAS INTO SERN GA. FAVORED THE HEAVIER GFS HERE GIVEN EXPECTED UNSTABLE CONDITIONS AND DEFINED BNDRY LAYER CONVERGENCE ALONG THE FRONT. .25-.50"+ AMTS DEPICTED. N FL... VERY MOIST WLY ONSHORE WLY FLOW EXPECTED TO PERSIST ACRS NRN TO CNTRL FL ON THE SRN EDGE OF THE STRONG ERN TROF. THIS SHOULD SUPPORT POTENTIAL FOR HVY PCPN DAY 1 OVR NRN TO CNTRL FL. THERE WL BE POTENTIAL FOR LOCALLY VERY HEAVY RAINFALL AMTS OF 2-3" AS THE PERSISTENT WLY ONSHORE FLOW MAY SUPPORT TRAINING OF CELLS. AREAL AVG 1-1.5" AMTS DEPICTED ON THE DAY 1 MANUAL QPF. SRN HIGH PLAINS... SIMILAR TO THE PAST FEW DAYS...THERE WL BE POTENTIAL FOR CONVECTION TO FORM ON THE NRN PORTION OF THIS UPR RIDGE OVR THE SRN ROCKIES/SWRN U.S. AS SHRTWV ENERGY ROTATES ARND THE RIDGE. THIS CONVECTION SHOULD THEN DROP SSEWD ACRS ERN NM AND WRN TX WHERE MOIST SSELY INFLOW SHOULD HELP TO MAINTAIN AND PROPAGATE THE CONVECTION SSEWD. WITH SSELY INFLOW INTO ANY CONVECTION HERE...IT SHOULD BE PROGRESSIVE...KEEPING AREAL PCPN AMTS IN THE .25-.50" RANGE...WITH POTENTIAL STILL FOR LOCALLY HEAVIER AMTS WITH ANY ORGANIZED CONVECTION. NRN GTBASIN/NRN ROCKIES... THE ETA AND GFS ARE IN FAIRLY GOOD AGRMNT THAT WELL DEFINED SHRTWV ENERGY OVR THE NRN GTBASIN THIS MORNING WL BEGIN TO TURN MORE TOWARD THE EAST ON THE TOP SIDE OF THE LONGWAVE RIDGE CNTRD THRU THE ROCKIES. CONVECTION MAY BECOME VERY ACTIVE AHEAD OF THIS VORT ACRS THE NRN GTBASIN AND INTO THE NRN ROCKIES DURG SUN AND THEN POSSIBLY INTO THE NRN HIGH PLAINS IN THE EARLY HOURS OF MON. THE GFS APPEARS TO SHOW ITS TYPICAL GRID SCALE PROBLEMS WITH IT HAVING A MUCH STRONGER VORT THAN THE ETA. HOWEVER...GIVEN THE WELL DEFINED NATURE OF THIS VORT...WE PREFER ITS .50"+ QPF AMTS OVR THE NRN ROCKIES AHEAD OF THIS SYSTEM. UPR MS VALLEY... SHRTWV ENERGY DROPPING SEWD ACRS SCNTRL CAN AND INTO THE UPR MS VALLEY WL SUPPORT CONVECTIVE DEVELOPMENT ALONG THE WARM FRONT PUSHING EWD SUN AFTERNOON INTO SUN NIGHT/EARLY MON ACRS NERN MN...NRN WI AND THE U.P. OF MI. CONVECTION LIKELY TO BE FAIRLY FAST MOVG ACRS THIS AREA...BUT THERE IS POTENTIAL FOR CONVECTION TO BECOME FAIRLY ORGANIZED ARND 0600 UTC. AREAL AVG .25-.50" AMTS DEPICTED..WHICH WERE HEAVIER THAN OPERATIONAL ETA/GFS...CLOSER TO SOME OF THE ETA/RSM SREF MEMBERS. NORTH AMERICAN MONSOON EXPERIMENT AREA... THE ETA AND GFS BOTH SHOW THE UPR RIDGE THAT HAS BEEN OVR THE SRN ROCKIES EXPANDING SLOWLY WWD ALONG THE AZ/NM BORDER DURG DAY 1. INCREASED SUBSIDENCE WITH THIS RIDGE SHOULD DECREASE CONVECTIVE ACTIVITY OVR THE SW COMPARED TO PREV DAYS. MOST ACTIVE MONSOON ACTIVITY WL REMAIN FARTHER TO THE NORTH OVR THE NRN GTBASIN AND INTO THE NRN ROCKIES ASSOC WITH THE WELL DEFINED VORT BOTH THE ETA AND GFS SHOW PUSH ENEWD ON THE TOP SIDE OF THE LONGWAVE WRN RIDGE. DAY 2... MID-ATLANTIC/NORTHEAST... DEEP UPR TROF OVR THE REGION SHD BE WEAKENING WITH TIME AS S/WV ENERGY SHEARS OUT TO THE NORTHEAST ALONG THE ATLANTIC SEABOARD. XPCT A SFC WAVE OF LOW PRESSURE TO LIFT NEWD OFF NEW ENGLAND BY LATE IN THE PD WHICH SHD ALSO TAKE THE AXIS OF DEEPER MOISTURE AND WARM ADVECTION PCPN OFF THE COAST. MID/UPR LVL FORCING SHD BECOME ILL-DEFINED OVERALL...BUT THE BROAD UPR TROF SHD STILL HELP SUSTAIN RATHER STEEP LAPSE RATES. AFTER AN INITIAL BATCH OF WARM ADVECTION RAINS EARLY ACRS NRN NEW ENGLAND...XPCT MORE OROGRAPHICALLY FOCUSED SHWRS/TSTMS WHICH WL BE DIURNALLY DRIVEN. PWS PER THE ETA SHD BE 1.25 TO 1.5 INCHES OVR THE INTERIOR AND THAT WL STILL SUPPORT LOCALLY HVY RAINFALL RATES. MANUAL PROGS LEAN TWD THE ETA AMTS. FL PENINSULA... SFC CDFNT WL MOV SLOWLY SEWD AS STG MID/UPR LVL TROF REMAINS OVER THE ERN CONUS. DEEP LYR SWLY FLOW WL CONTINUE TO BRING AN ABUNDANCE OF MOISTURE EWD FRM THE GULF OF MEX WITH PWS PROGGED TO REMAIN AOA 2.0 INCHES THIS PD. THE COMBINATION OF THE DEEP MOISTURE/INSTABILITY AND THE CDFNT WILL TRIGGER CONVECTION ACRS ESP CNTRL AND SRN FL. MANUAL PROGS LEAN TWD THE GFS WHICH HAS GOOD SUPPORT FRM THE UKMET. THE HEAVIEST RAINS SHD BE ON THE W COAST OF THE STATE WHERE THE BETTER FETCH OF MOISTURE OFF THE GULF OF MEX WL BE NOTED. XPCT LOCALIZED 1 TO 2 INCH AMTS HERE. NRN PLAINS/UPR MS VLY... LATEST IR/WV SAT IMAGERY SHOWS A WELL-DEFINED MID/UPR LVL S/WV OVR THE CNTRL GRT BASIN WHICH IS PROGGED BY THE ETA/GFS AND UKMET TO ROUND THE TOP OF THE STG SUBTROPICAL RIDGE OVR THE ROCKIES AND DROP SEWD TWD THE UPR MS VLY. XPCT THE ENERGY TO HELP INDUCE A FAIRLY WEAK LEE-SIDE LOW AND EJECT EWD ALONG A CDFNT WHICH WL BE SLIPPING SEWD FRM ONTARIO. XPCT THE FRONT TO GRADUALLY STALL OUT AS THE SFC WAVE MOVES TWD THE UPR MS VLY. MEANWHILE...HIGHER PWS SHD BE POOLING ALONG THE FRONT AND HELPING TO ENHANCE HIGHER THETA-E. THE GFS PROGS 1.75 INCH PWS AND SWLY H8 FLOW OF 30 KTS INTO THE FRONT AHEAD OF THE SFC WAVE. COMBINATION THE MOISTURE AND ISENTROPIC LIFT WITH THE ARRIVAL OF THE VORT ENERGY SHD LEAD TO MCS DEVELOPMENT INITIALLY OVR THE NRN PLAINS AND THEN PROPAGATING SEWD WITH THE MEAN DEEP LYR FLOW. MANUAL PROGS HEAVILY FAVOR THE WETTER GFS...BUT NOT QUITE AS HVY SINCE THE GFS SEEMS TO HAVE SOME CONVECTIVE FEEDBACK IN IT. PAC NW/NRN INTERMOUNTAIN REGION... AN UPR TROF MVG THRU THE PAC NW WL BE INTERACTING WITH SUBTROPICAL MOISTURE FIRMLY ENTRENCHED OVR THE GRT BASIN TO HELP SET OFF MAINLY DIURNALLY DRIVEN AND OROGRAPHICALLY ENHANCED CONVECTION THIS PD. PWS LOCALLY OVR 1 INCH WL AND FAIRLY STEEP LAPSE RATES WL ENHANCE THE CONVECTIVE THREAT. MANUAL PROGS FAVOR A BLEND OF THE ETA AND GFS. CNTRL ROCKIES/NAME AREA... NO MAJOR DIFFS COMPARED TO THE PREVIOUS PACKAGE. STRONG SUBTROPICAL RIDGING WL REMAIN IN PLACE THRU THE PD OVR THE SWRN CONUS. MOISTURE REMAINS TRAPPED UNDER THE RIDGE AND MDLS HAVE BEEN GENERALLY UNDERDOING THIS MOISTURE. HOWEVER...WITH LACK OF ANY SIGNIFICANT WX FEATURES...EXPECT MAINLY DIURNAL ORGORAPHICALLY ENHANCED TSTMS AND QPF AMTS OF 0.25 INCHES OR LESS. ORAVEC/ORRISON GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV 24HR QP VT 19/12Z 0.01 448884 449915 457942 468962 486965 532952 546920 547866 529838 511838 488837 482839 478841 474844 469848 467853 463856 457865 450878 448884 0.01 457794 480713 478675 450645 415654 358706 295771 288778 276793 270802 267814 266835 262850 263919 272973 301025 342057 353062 359067 364069 374090 376094 383094 393091 401090 401095 400101 391108 390114 391120 393127 392136 389151 386157 384162 384167 386170 389176 395180 403180 415179 422181 427186 430192 436196 445201 449216 474217 485222 489224 492230 494237 494241 492243 490243 487237 479235 476233 474236 474242 480252 482260 485270 496278 517247 528211 532165 519124 509094 502066 494042 487038 479048 472057 468060 465068 461068 456068 451066 439061 427058 406048 393042 389040 384035 376027 368015 362006 355999 344997 334997 323996 318996 315995 305970 303960 302953 303949 305899 305873 309863 314853 319842 323839 328838 333839 339837 347831 351826 358823 364822 370823 374826 376830 382839 386846 389848 396849 401852 407855 411855 423849 430843 434840 438837 440834 442826 446814 447809 451803 457794 0.01 224064 226069 231074 240080 250086 258092 277104 290108 297108 304110 312117 315119 318119 323118 329114 333109 332106 326102 316097 307090 298081 290075 286071 280068 269063 259057 253051 236035 228028 0.25 516894 494866 472864 463871 456894 460910 466923 474933 483936 494925 506909 516894 0.25 441779 443719 441676 428667 406686 386710 348747 321772 314777 295789 289795 283798 279807 276814 274823 272834 271853 271871 272891 273913 277939 279943 282946 285948 288948 290946 296932 298923 297909 296899 296886 297876 298869 304853 309845 313837 319830 325827 331826 336823 339820 344814 349807 355798 357795 358789 357784 358778 359774 362773 366775 373781 380789 385794 393797 395798 399804 400811 403819 405822 411825 414825 418823 423819 425816 441779 0.25 500168 501161 501153 500143 496135 493126 494097 493089 491079 489074 487071 484072 481075 476080 470083 464087 458093 456094 452094 444093 435092 429088 426089 424094 425099 420107 416112 413114 414118 419122 437128 437133 435137 433149 436156 440164 444171 449176 453176 454174 458168 461165 464162 471159 476159 483160 488164 492170 495171 498170 500168 0.25 369040 367034 364029 359019 357015 355013 351012 339010 332011 328013 323016 322018 322022 327032 334041 338044 344047 348048 355049 363048 367047 369040 0.25 281084 280083 277081 275079 272079 270081 272083 272084 272087 274088 277089 279087 280086 281084 0.25 259072 258071 257069 256067 253066 253065 250063 249063 248062 245061 242062 241063 242064 244066 245067 246069 248069 250071 253072 256073 258072 259072 0.50 372772 392786 407801 414803 424796 429783 425764 417740 418728 427714 433699 435682 419681 404702 381729 359744 356748 356751 358757 364763 372772 0.50 492144 492139 490134 487127 486122 485115 488106 487098 485090 483086 480087 476089 470090 459099 449099 443100 438104 441109 446117 450122 455128 459135 465150 471146 479148 484149 488148 492144 0.50 359040 357036 354032 351029 349023 345021 343020 337019 332021 330025 333028 334035 337038 341039 344041 349043 355042 359040 0.50 310814 307807 303803 296799 292799 288801 284805 280814 277825 275835 274849 274860 276885 277902 279912 282917 285917 289915 291911 292906 292880 295867 298857 307836 310826 310814 1.00 386733 373746 370751 373760 379762 389761 399767 406772 409763 405731 419711 415696 405707 393726 386733 1.00 299818 298812 296810 290810 286814 282822 281829 280839 279849 279859 281865 281868 284868 288861 291852 293844 295836 298826 299818 1.50 399751 400746 398743 395741 392742 390744 393747 394748 395749 398751 399752 399751 1.50 294821 293819 290819 288823 287826 287827 286830 285832 285834 285837 287839 290837 290835 291833 292831 293828 293827 294824 294822 294821 24HR QP VT 20/12Z 0.01 224073 231076 237080 243085 250092 260102 267107 276112 283114 290119 304120 308118 311117 313119 317121 320120 324111 329110 332108 336114 339124 341129 344131 348134 353134 359131 361126 361118 357110 353106 351103 347094 346090 345082 345078 344076 341073 335073 330075 316082 311083 307081 305077 302075 295070 286066 271059 256051 243042 235037 228034 0.01 557124 555119 554112 552103 549097 545088 542082 534071 529063 524058 520053 515049 508048 503042 498036 496032 496026 497016 497003 494985 489971 482956 474940 466925 463919 464914 468908 475898 483888 492879 501869 505863 509856 510845 510842 509834 504825 499820 495818 489817 486814 485808 481801 476796 471793 470788 474778 477772 479764 483747 486733 487724 488714 488700 487690 485680 482673 478666 471657 465652 460649 456647 450645 444645 441645 438646 434646 427648 413656 406665 404673 402686 402696 401704 400712 397719 395725 390731 382741 379742 376740 373741 370742 366745 359749 350757 344765 340775 339782 337788 330797 327803 326811 324826 324841 326852 332861 338865 342867 347867 351867 354866 365857 375849 384844 392840 407836 419831 428827 434824 436824 434828 432832 429837 423848 419864 417877 417889 417899 420922 426939 429944 431950 431955 429961 426963 421967 408976 386986 375992 372996 371000 371004 373008 377012 384013 390012 406011 418011 431012 435016 430020 418030 412030 404027 378029 371029 364028 348024 328026 323025 317022 313017 311012 308007 305006 302001 299998 294996 287996 278001 268008 260014 259016 259021 263023 267023 271023 269031 267037 269044 272049 278051 284053 289055 300060 305058 310055 313056 319058 324063 328066 337065 364090 361082 364075 368078 371086 378090 381090 384089 385084 387079 389081 393083 397083 401082 404080 405075 407072 410073 415070 419065 421062 424060 428060 433060 436063 440063 445060 450060 457063 460068 465077 464078 460077 457074 446068 439065 432068 427072 424079 422085 418089 412091 404093 392101 387105 384110 378119 376123 376130