FXUS04 KWBC 141003 PAA QPFPFD QUANTITATIVE PRECIPITATION FORECAST DISCUSSION NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD 602 AM EDT FRI MAY 14 2004 FINAL DAY 1...DAY 2 AND DAY 3 QPF DISCUSSION VALID MAY 15/1200 UTC THRU MAY 17/1200 UTC REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR ...FINAL DAY 1... BOTH THE 06 UTC ETA/GFS CAME IN DRIER AND THEIR INITIALIZATIONS WERE VRY POOR. BOTH THE ETA/GFS MISSED THE SVRL INCHES OF RN THAT FELL OVR SCNTRL TX BETWEEN 06 AND 12 UTC. THE 06 UTC MM5 CAME IN MUCH WETTER. LATEST WV IMAGERY SHOWS AN MCV N OF VCT WITH A SQUALL LN WELL OFFSHORE. PROFILER DATA FM LDBT2 HAS SHIFTED TO STG NWRLY AT 8H...WHICH USUALLY IS A SIGN OF A DRIER FCST....BUT THE SYNOPTIC BNDRY IS STILL ACRS CNTRL TX...SO WL BACK OFF ON THE PRVSLY HVY RNFL AMTS...BUT NOT TOTALLY. OTHER CHNGS ACRS THE CONUS WERE MINOR. ...PRELIM DAY 1... ...SYNOPSIS... SHARP MIDLVL TROF ALNG THE AXIS OF THE HI PLNS WL SHIFT EWD THIS PD AND BCM A BROAD FLAT TROF FM THE ROCKIES THRU THE CNTRL U.S.. STG ERN U.S./WRN ATLC RDGG WL REMAIN QUITE STG. A FLAT RDG WL MOV OVR THE WRN U.S... THE MAIN FOCUS FOR PCPN WL BE THE FNTL BNDRY DRAPED FM THE GRT LKS SWWD INTO SRN TX THAT WL MOV VRY SLOLY EWD. ...TX/LA... THE MAIN AREA OF HVY/XCSV RNFL SHLD BE ACRS SRN TX INTO SWRN LA TDA. THE MDLS ARE GNRLY ON THE SAME PAGE WITH THE SYNOPTIC MASS FIELDS...BUT LRG DIFFS SHOW UP ERLY TDA WITH RESPECT TO QPF. THE ETA SEEMS LIKE THE MORE SENSIBLE QPF ORIENTATION SOLU CONSIDERG THE FCST OF THE SYNOPTIC FNTL BNDRY...BUT THE GFS MGT AGN HAV THE BETTER AMT SOLU. IT WAS CORRECT LAST NGT WITH THE 5+ INCH RNS OVR ERN TX AS SBTRPCL MIDLVL ENERGY LIFTD NEWD. IT'S FCSTG 13+ OVR HOU TDA. LATEST SFC ANLYS SHOWS A MESO HI OVR SERN TX/SWRN LA WITH RDRS SHOWG PCPN DIMINISHG THRU THIS REGION. THE OUTFLOW BNDRY HAS PUSHED INTO THE GULF...BUT XTNDS WWD TO BETWEEN CRP AND BRO. THE MAIN SYNOPTIC BNDRY CONTS TO PUSH SEWD AND XTNDS FM NERN TX INTO THE BIG BEND REGION. ANOTHER MIDLVL SHRTWV OVR LRD IS MOVG EWD AND HELPG TO IGNITE ADDTNL XCSV RNFL OVR SRN TX ERLY THIS MRNG NR THE INTERSECTION OF THE OUTFLOW BNDRY AND PSBLY A DRYLN. ADDTNL CNVCTN IS PSTND ALNG/AHD OF THE MAIN SYNOPTIC CDFNT WRKG THRU CNTRL/SRN TX. THE LATEST RUC/ETA & GFS HAV THE LRD VORT WELL INITIALIZED AND ALL CARRY IT ENEWD TDA. THE DIFFS ARE WITH THE GFS AS IT INCRS THE STRNGTH RPDLY THIS MRNG...WHILE THE OTHER MDLS BEGIN TO SHEAR THE SYS. THE MDLS ALL SHOW MIDLVL HGTS FALLS COMG TO AN END ACRS THE REGION WITH WEAKENG MID/UPR LVL FLOW...SO THE VORT SHLD LKLY SLOW ITS FORWARD PROGRESS...WHICH LENDS MORE SUPPORT TO THE HVIER GFS SOLU. ALSO ON THE SIDE OF THE GFS IS THE LATEST RDR LOOPS FM HGX THAT SHOWD CNVCTN THAT WAS MOVG SWD OVR THE NRN GULF...NOW COMG BACK N AS INCRSG SRLY FLOW...ABV THE SFC...AHD OF THE VORT IS SUPPORTG SOME ISENTROPIC LIFT OVR THE OUTFLOW BNDRY. ALSO...REGIONAL RDR LOOPS SHOW A SLGT CYCLONIC TWIST IN THE PCPN OVR SCNTRL TX. LATEST PROFILER DATA FM LDBT2 SHOWS VEERG FLOW INDICATG THE HI OVR SERN TX/SWRN LA IS MOVG EWD. MSTR IS NO PRBLM WITH PWS NR TWO INCHES. SATL PW LOOPS SHOW A STG LINK TO DEEP MSTR WELL INTO THE GULF AND CARIBBEAN. THE UPR FLOW IS FCST TO REMAIN DIFL WITH UPR JET ENTRNC REGION DYNAMICS AGN SUPPLYG STG UPR LVL VENTILATION OVR THE REGION. ONE FLY IN THE OINTMENT IS THE COMPLEX MOVG TWD CRP THIS MRNG. IF THIS SYS MOVS INTO THE NRN GULF AND DOES NOT LIFT NEWD...IT COULD CUTOFF THE PCPN OVR SERN TX. AT THIS TIME...AM NOT PLAYG THIS SCENARIO. ALL GUID DOES PT TWD ADDTNL LCLLY HVY RNS OVR SERN TX TDA WHICH SPRDS INTO SWRN LA THIS AFTN. XPCT 1-2 INCH PER HR RNFL RATES WITH ISOLD 5+ TOTALS BY THIS EVE. ...LWR MS VLY INTO THE GRT LKS... SVRL MIDLVL SHRTWVS WL CONT LIFTG NEWD AND OVR THE FNTL BNDRY THAT WL MOV SLOLY EWD. THE MDLS SHOW THE SFC CVRG WEAKENG...WHILE ALSO SHOWG WEAKENG MIDLVL HGT FALLS. THERE STILL SHLD BE A FEW POCKETS OF MORE ORGANIZED RNFL. ONE FM THE LWR MS INTO THE TN VLY...AND A SCND OVR THE GRT LKS. THE MORE SRN AREA SHLD BE FOCUSED ALNG THE OUTFLOW BNDRY THAT HAS PUSHED TO THE MS RVR...BUT ADDTNL DVLPMENT COULD OCCUR THIS AFTN ALNG THE MAIN SYNOPTIC BNDRY. MDLS SHOW DECENT SFC BASED INSTBLTY THIS AFTN AND THE UPR FLOW SHLD REMAIN QUITE DIFL AS THE MIDLVL TROF PUSHES INTO THE SERN U.S. UPR RDG. THIS AREA WL HAV DECENT MOIST INFLOW WITH PWS ARND 1.50 INCHES. THE SLOW MOVMENT AND LKLY S TO N TRAING COULD LEAD TO ISOLD 1-2 INCH RNS IN A COUPLE OF HRS. THE SCND AREA OVR THE GRT LKS SHLD BE LINKED TO THE VORT LIFTG THRU THE MID MS VLY THIS MRNG. MDLS SHOW THIS SYS CONTG TO LIFT NWD AND INTO THE GRT LKS REGION BY LATER TNGT. ALTHOU INSTBLTY WL BE LESS...THE STGR MIDLVL DYNAMICS SHLD OVRCOME THE LACK OF SFC BASED INSTBLTY THRU THIS REGION. ISOLD ONE INCH RNS WL BE PSBL IN A SHRT TIME. THE REST OF THE CONUS SHLD SEE MOSTLY DRY WX...BUT POCKETS OF LGT PCPN ARE PSBL OVR THE NR ROCKIES...NRN PLNS AND OH VLY/APPLCHNS/NERN U.S.. DAY 2... LOCALLY HEAVY RAINFALL STILL LOOKS PROBABLE ALONG THE GULF COAST ALONG THE TRAILING END OF THE SLOW MOVING COLD FRONT SLIDING EWD. MANUAL QPF SHIED AWAY FROM THE GFS WHICH SUFFERS FROM MASSIVE GRID-SCALE FEEDBACK OVER ERN TX. ABUNDANT MOISTURE INFLOW AHEAD OF THE FRONT WILL BRING QPF EXCEEDING 1 INCH ACROSS SRN LA EXTENDING NEWD INTO W-CNTRL MS. A BAND OF QPF IN THE .25 TO .50 INCH RANGE WILL EXTEND FARTHER TO THE NORTHEAST AS THE FRONT MAKES STEADY PROGRESS TOWARD THE COAST. A WEAK COLD FRONT WILL DROP INTO THE NRN PLAINS DURING THE LATER PORTION OF THE PERIOD...BRINGING LIGHT RAIN TO THE DAKOTAS AND UPPER MS VALLEY. IN THE PACIFIC NORTHWEST...GENERALLY FOLLOWED THE SLIGHTLY WETTER GFS HERE AS ITS UPPER LOW FCST IS SUPPORTED BY THE UKMET. DAY 3... PCPN CONTINUES OVER THE SOUTHEAST AND MID-ATLANTIC THIS PERIOD ALONG THE REMNANTS OF THE FRONTAL BNDRY AIDED BY IMPULSES IN THE SUBTROPICAL STREAM. MODELS ACTUALLY NOT THAT DIFFERENT BY THIS TIME ALTHOUGH THE GFS DOES SPREAD MORE .25 TO .50 INCH QPF NWD THROUGH ERN TX/SERN OK/WRN AR. SINCE THE GFS QPF IS LIKELY THE RESULT OF WHAT REMAINS OF ITS EARLIER CONVECTIVELY INDUCED VORT CENTER...HAVE OPTED TO GO WITH THE ETA OVER TX AND LA. A FRONTAL SYSTEM WILL BECOME ORGANIZED OVER THE HIGH PLAINS AND GRADUALLY MOVE NEWD THROUGH THE UPPER MS VALLEY AND INTO THE GREAT LAKES. MANUAL QPF GENERALLY WENT WITH A MODEL BLEND ALTHOUGH THE .25 INCH ISOHYET WAS EXTENDED FARTHER WEST...SIMILAR TO THE GFS TO REFLECT THE INFLUENCE OF ITS PREFERRED SLIGHTLY STRONGER UPPER SYSTEM COMING ACROSS THE NRN ROCKIES. ECKERT/MAUSSER GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV 24HR QP VT 15/12Z 0.01 525730 523718 518709 513707 509706 502707 497708 491711 488712 485711 484707 485701 484693 482686 480682 477678 476673 472671 467670 463674 462683 464691 465700 466706 466715 465721 462728 455736 445744 434753 428755 422758 416762 410768 400779 391784 385788 381793 378796 377799 374801 371805 364813 358822 348841 345847 342852 334860 327867 317876 309883 306887 299889 291890 284897 276917 270926 268931 264936 259942 250948 248951 245957 243966 244973 245979 248985 250988 258994 268999 275004 282010 290015 295018 298017 295990 295984 297978 299973 303966 317953 331937 349926 364922 371919 377916 388912 392912 397914 402916 406920 405927 403934 403941 407942 411939 420932 431924 441915 448907 455898 462889 470878 475863 478857 482855 488851 493845 498838 499829 500821 505816 509812 513806 516799 518793 518784 518777 517767 514760 516754 516750 518746 521744 523738 525730 0.01 526208 525201 523197 517191 512184 512178 512171 513162 512156 509151 506150 502148 500148 498145 497136 495124 493118 490117 487113 487108 488099 491086 494077 503063 514045 517035 514030 507030 499035 495040 491047 486055 482064 481069 480075 480090 479104 479111 477115 470132 471139 473141 477145 479150 482157 484162 484165 483168 483174 488181 492189 496195 502203 509208 517210 524210 526208 0.01 506235 506234 503230 503229 503224 502220 502219 499216 498213 497211 494209 491211 493216 493217 493221 493222 492225 492227 493230 494231 497235 498236 499238 502240 505239 505237 506235 0.01 477107 473100 468098 464099 460100 457097 454094 450094 446096 445101 444105 441107 439108 438111 441114 449117 454116 456114 460112 464114 470116 473115 475111 477107 0.01 459156 458152 453148 451144 445143 442141 439138 436139 436144 436148 438153 443158 446161 448167 449171 451176 454178 455176 455168 455163 457160 459156 0.01 461988 459982 456978 451973 443968 436965 431966 428969 424970 420974 416982 415987 413991 411002 412014 416025 414029 412034 409041 409047 411049 412049 417045 421041 428034 435031 440029 446028 451023 455001 461988 0.25 502787 497771 494771 489772 479779 470788 463791 456797 450804 447809 445814 431827 424834 419843 412850 403855 394859 391858 392854 396844 399835 400826 398820 394817 390816 387817 382819 379821 366834 354846 348854 344864 341869 334876 328882 322887 308896 300902 295909 286922 277932 270940 265944 259949 253957 251962 250967 250973 252978 254982 256985 259986 265986 270983 273977 279972 291970 311948 322936 336922 342918 349913 356908 363901 368896 372893 377890 382889 388888 398888 415888 426885 436881 441879 447875 454870 457865 459860 463850 473834 478824 481819 483816 488808 490804 495800 500794 502787 0.25 421780 420779 417778 414779 411780 409783 406783 403785 402786 403790 405790 408790 411789 413787 416786 419784 421782 421780 0.50 488791 487787 485786 479788 474792 469796 465799 463805 463811 464815 470815 476811 480805 483802 487797 488791 0.50 451842 451838 448836 446836 445836 442837 440838 439839 437844 441845 444845 447845 449844 451842 0.50 450859 449856 446855 437858 429861 421864 412868 405872 402878 403881 406882 415880 423878 429877 438874 444870 450864 450859 0.50 387833 386829 384827 381827 377830 371834 365842 360849 353857 347866 343872 335880 329887 321894 306903 298911 292919 282931 275939 268945 262950 257958 254965 253972 255979 258981 262981 266974 272969 278967 285967 290965 293963 299957 324928 339915 351903 359895 366887 370880 374869 379861 384849 386842 387833 1.00 378848 376841 370848 360860 354866 350874 345880 339884 327897 314904 307909 300915 291926 287932 282938 273949 267954 264961 265963 269963 279962 286963 290961 293959 302949 306941 310934 321924 334913 343903 347895 353887 361876 371861 374857 376853 378848 2.00 294933 285945 281952 279956 283957 286958 291956 295952 298945 301938 304930 305924 300923 297927 294933 3.00 289954 292951 294947 294944 292945 289948 286952 289954 24HR QP VT 16/12Z 0.01 508637 508650 507658 509664 512665 516673 518681 519689 519699 518706 516712 511717 505721 495727 486734 465753 445771 437780 430788 416807 371884 369888 366890 356899 348908 341915 330932 326938 321948 317956 308964 298969 293970 288974 278978 273979 266979 261978 258977 257973 258969 264949 271928 277913 280904 284893 288874 292864 297853 308839 315822 324815 328813 335809 340804 343799 348790 357773 367754 387711 392702 398693 401689 406686 411685 415689 416696 416702 418714 433695 449676 457665 463655 479632 488622 498615 0.01 560884 560877 558871 557868 554866 547868 540872 534875 529877 522879 514881 507886 502892 495900 488903 477893 470889 466890 459895 454901 450907 446914 444922 440934 436950 433958 430965 425970 421973 415976 408978 401979 395983 387987 383993 395001 405008 411010 417015 421021 423026 422034 423041 427044 430046 434045 440041 446024 449018 452012 455013 456016 458022 467035 476047 486054 491056 500058 507055 513050 517044 520035 523028 526018 530004 534983 538960 540944 544937 548931 552919 556904 559894 560884 0.01 530239 531230 531221 530213 527208 520199 514192 511189 509182 507174 505168 500156 497149 491139 484129 482123 481116 481103 478089 476084 472079 469078 466079 464081 456088 453089 448088 437086 427087 423089 421092 419099 419108 420115 423119 430125 432129 432136 430152 429170 427183 424184 421186 422190 422194 422202 419219 418225 419233 422237 427246 433254 442259 451260 472259 476258 481258 486261 492264 499268 507270 513272 518272 0.01 353054 352048 350042 345041 341041 330043 321046 308049 299049 280045 267045 262047 260051 259058 260065 262068 266071 274075 283078 293081 305083 311083 317082 321081 325078 332070 341065 349060 353054 0.01 282802 280796 277795 270794 264794 259796 249800 245804 244808 251815 258818 264822 272826 278827 284825 286823 284817 282812 281809 281806 282802 0.25 532921 533914 531910 524911 517914 510917 499924 495928 490934 483944 480953 481963 480970 483975 489975 493973 504967 511961 515957 520952 526944 528940 530931 532921 0.25 492216 490211 485206 480205 474204 463204 459204 454201 464189 467183 467178 467174 464165 461159 458155 453153 448154 446158 445167 445178 444196 443202 440206 437210 434217 433225 436230 441232 446234 452235 455235 461233 468227 476224 484222 490219 492216 0.25 441720 437719 432721 423729 413736 406736 403734 403728 403724 401720 397724 395732 390748 388757 387766 385775 384780 380788 375795 371801 365808 353819 334839 303890 294900 289906 285914 282926 278940 275954 277961 279963 284964 292961 298957 307949 316937 323924 329913 340902 349891 351886 351883 349876 353870 359865 365860 370855 379843 388828 394815 401800 406784 413767 420754 431740 438728 441720 0.25 442003 442999 442995 442991 441989 438987 435989 433991 432992 430997 431001 431004 431008 433012 434013 437014 440012 440011 442007 442003 442003 0.50 450179 449186 451188 455185 457183 459180 456177 453174 451177 450182 450179 0.50 398788 396786 392784 387791 376807 367819 361826 353831