FXUS04 KWBC 100709 PAA QPFPFD QUANTITATIVE PRECIPITATION FORECAST DISCUSSION NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD 308 AM EDT FRI SEP 10 2004 PRELIM DAY 1 AND DAY 2 QPF DISCUSSION VALID SEP 11/1200 UTC THRU SEP 12/1200 UTC REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR ...PRELIM DAY 1... ...SERN U.S./FLORIDA... BOTH THE ETA AND GFS ARE CALLING FOR THE AMPLIFICATION OF THE WEAK UPPER TROF ACROSS THE SERN U.S. A STG LVL MSTR CNVGNC AXIS WILL BE ALIGNED ALONG THE SE ATLC COAST WHERE A STG LVL ELY FLOW WILL IMPINGE ON THE FEATURE. FVBL RIGHT ENTRANCE REGION JET DYNAMICS WILL ALSO BE AVBL TO ENHANCE THE SYNOPTIC SCALE LIFT. BOTH THE ETA AND GFS QPFS ARE IN THE SAME BALLPARK WITH THE GFS HAVING SOME FEEDBACK PROBLEMS. MODEL QPFS ARE BOUNCING AROUND FM RUN TO RUN ON SPECIFICS AS THE MID LVL IMPULSES EMBEDDED ALONG THE MID LVL SHEAR AXIS ARE DIFFICULT FOR THEM TO DEFINE. HOWEVER BOTH OF THEM AGREED TO SHIFT THE PCPN AXIS A LITTLE FARTHER TO THE NORTH AND WEST FM PREVIOUS RUNS. FOR NOW STAYED CLOSE TO THE ETA QPF SOLUTION WHICH SEEMED A GOOD FIT TO BOTH THE ETA AND GFS MASS FIELD FCSTS. ...NRN PLAINS/UPPER MS VLY... BIG MODEL QPF DIFFERENCES HERE WITH THE GFS BEING MUCH MORE AGGRESSIVE WITH AMTS ASOCTD WITH A BROAD SHRTWV TROF AND ITS CDFNT WHICH ADVANCES EWD ACROSS THE REGION TODAY. THE ETA IS VOID OF PCPN ALONG THIS BNDRY WHICH SEEMS UNUSUAL GIVEN THE REASONABLE PW AVBLTY AND DESTABILIZATION BOTH THE ETA AND GFS ARE INDCTG. THE GFS QPF HAS HAD VERY CONTINUITY HERE FOR THE PAST FEW RUNS ON PLACEMENT. OPTED TO BUY INTO THE GFS THOUGH BACKED OFF ON ITS AMTS GIVEN THE LACK OF SUPPORT FM THE ETA. ...PACIFIC NW... LATEST STLT IMAGERY SUPPORTS MODEL FCSTS OF AN INTENSE CYCLOGENESIS OFF THE BC COAST BY THIS MRNG. THIS WILL BRING A STG FRONTAL BAND TO THE PACIFIC NW COAST BY THIS EVNG ACCOMPANIED BY A STG ONSHORE MSTR FETCH. THE NET RESULT WILL BE MDT TO HVY PCPN TOTALS WITH A DISTRIBUTION BASED ON STG WLY OROGRAPHICS. WITH GOOD AGREEMENT BTWN THE ETA AND GFS MASS FIELD FCSTS...THE ETA AND GFS QPFS ARE IN GOOD AGREEMENT AND APPEAR REASONABLE. ...DESERT SW/SRN GREAT BASIN/S CNTRL ROCKIES... A PLUME OF HIER RH TRAPPED UNDER A BUILDING SWRN U.S. UPPER HI CELL WILL CONTINUE TO BE THE FOCUS FOR SCTD SHWRS LATER THIS AFTN AND EVNG. DAY 2... SE COAST/FLORIDA.. MODELS ARE DEPICTING INCREASING ONSHORE FLOW OF MOISTURE IN WAKE OF DISSIPATING STATIONARY FRONT. THIS RESULTS IN RAINFALL A BIT FURTHER TO THE WEST OVER THE CAROLINAS AND GA. THAN EARLIER THINKING. HEAVIEST RAINFALL AMOUNTS SHOULD BE ALONG THE CAROLINA COAST TO GA AND NRN FL. EVEN THE NORMALLY DRY ETA HAS INCREASED PW VALUES TO NEAR 2 INCHES IN THIS AREA. THE SHORTWAVE SUPPORT REMAINS MINIMAL SO SOME UNCERTAINTY IN RAINFALL AMOUNTS. HAVE LEANED TOWARDS THE GFS...WHICH HAS SUPPORT FROM THE UKMET. SOUTH TX... SCATTERED CONVECTION IS EXPECTED ACROSS SOUTH TX DUE TO MOIST EASTERLY FLOW INTERACTING WITH WEAK COASTAL TROF. LITTLE DIFFERENCES AMONG THE MODELS ABOUT RAFL AMOUNTS...SO LEFT AMOUNTS GENERALLY ONE-QUARTER OF AN INCH AND LESS. UPPER MS VLY/UPPER GREAT LAKES... UPPER TROF MOVING ACROSS THE UPPER MS VALLEY INTO THE UPPER GREAT LAKES WILL PUSH A COLD FRONT INTO THE AREA. SOME CONVECTION IS POSSIBLE ALONG THE COLD FRONT. SOME UNCERTAINTY ABOUT HOW MUCH INSTABILITY WILL BE AVAILABLE FOR CONVECTION TO WORK WITH. THE MODELS HAVE SLIGHT DIFFERENCES IN THE SPEED OF THE UPPER TROF AND HOW FAST THE SURFACE FRONT MOVES THROUGH. HAVE WORKED A COMPROMISE OF THE GFS/UKMET/ETA FOR LOCATION AND AMOUNTS. PACIFIC NW/NRN ROCKIES AND CNTRL BASIN... UPPER TROF WILL WORK INTO THE PACIFIC NORTHWEST DURING PERIOD AS GULF OF AK LOW MOVES INTO WESTERN CANADA. THIS WILL RESULT IN SOME RAFL OVER THE PAC NW AND PARTS OF THE THE NRN ROCKIES. THE 00Z RUN OF THE GFS WAS SLOWER IN MOVING SFC FRONT AND ASSOCIATED PCPN INLAND...WHICH RESULTS IN LOCAL AMOUNTS OF .50 INCHES IN THE HIGHER TERRAIN NRN IDAHO. PREFERRED THE GFS FOR LOCATION AND AMOUNTS IN THIS AREA. OTHER SHOWERS WILL DEVELOP OVER THE CNTRL BASIN IN RESPONSE TO LOWERING UPPER HEIGHTS. KORTY/BANN GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV 24HR QP VT 11/12Z 0.01 503643 500633 496627 492627 486628 483624 478619 474618 469622 463627 457634 449638 443643 439647 440656 441660 444668 447678 449691 448697 444703 439713 437719 434722 431724 426727 427731 436732 442730 447726 453721 460716 470708 483698 491691 499677 504664 504651 503643 0.01 542193 541187 539181 537175 533171 523157 516149 513146 507143 501140 492135 486130 482128 476128 475130 474135 478142 482145 483149 481151 475151 470152 467156 466159 465166 476183 476192 472199 466204 461204 456207 454210 451210 447212 443212 440214 436215 432218 432222 433224 438230 432232 425234 422237 420243 421245 425249 434253 471263 476269 482279 493291 499295 505296 512290 523261 523260 523255 522250 522249 520245 520243 518239 517237 517234 516229 517224 520221 522223 525225 528227 529228 530230 533231 534230 0.01 519872 518862 515856 511851 505846 501846 495847 490849 485852 460864 455869 453874 450885 446896 439909 429928 424938 422944 420953 419957 419966 418979 418987 422993 427997 432997 438987 440983 443980 447977 453974 459976 464979 466983 465988 464993 461005 458020 457027 456036 453048 451051 451056 451064 455064 460061 465057 469051 472046 474041 479032 482028 487023 493020 498014 504004 506998 507994 509986 509977 510968 514960 517948 520934 521929 522918 522911 521899 519889 519879 519872 0.01 358728 356722 352720 349724 344729 339735 334747 330759 323769 318774 312778 301787 290792 278795 272796 265794 254796 248784 246782 243787 242802 242812 246823 250829 255832 266835 270837 274840 273851 271864 271873 274883 277886 282887 281897 279910 280915 283916 288914 295907 302898 306888 311874 314863 319852 324849 328845 333838 336831 343809 348797 352791 356782 357778 358771 359758 360740 358728 0.01 418029 419022 417018 414020 412026 408035 403042 395050 389056 384056 380058 369059 365061 364065 367072 369076 369081 366090 366093 370098 373101 377103 382101 385096 386094 389095 392099 395100 396097 401088 402083 405079 412075 414072 415068 415064 412060 409049 415038 418029 0.01 392116 393113 392111 386112 380111 376111 370114 365114 360112 351108 343104 341106 341109 343116 345119 346123 342124 340127 341130 342134 341138 341142 344147 346149 349152 351156 357158 360161 362162 365162 366157 364152 363150 360149 357149 359137 359131 365129 368129 371132 373135 377133 389120 392116 0.01 344178 346175 346172 345168 344166 343164 342162 340160 339160 337159 334159 333163 336166 337167 338170 339170 340174 341175 343178 344178 0.01 277948 273942 269942 265944 254952 243963 239967 236973 234981 235990 240004 245011 250015 253017 259017 264013 267005 268996 267985 270980 275973 275964 276955 277948 0.25 472652 472651 469653 469654 470656 472652 472652 0.25 533210 534205 533201 532194 528185 524179 516169 508160 505157 500156 495158 491163 486165 485170 486174 491180 495185 497190 499195 501196 505197 510199 514204 520209 527212 533210 0.25 516267 517260 516252 513242 512236 509229 505220 498208 494205 489202 479205 471209 463213 459215 455215 451219 450221 452224 454227 454231 453231 448233 443235 440240 442243 444245 451246 462247 467250 474254 481261 493278 497283 501286 504286 508283 514272 516267 0.25 508900 507894 508887 506884 503888 497899 494906 492915 490920 488922 486926 483934 483940 480958 480966 481974 482977 484979 486978 490974 497960 503948 507940 508933 508914 508900 0.25 352761 351752 348748 344748 337759 325779 317790 307799 301803 292807 288810 283814 280819 281826 285837 285843 285850 285858 288864 292868 296869 300867 307858 311853 316847 324839 328835 331828 334818 339804 344792 349779 352769 352761 0.25 258969 259966 259963 257962 255964 254965 252967 251967 250970 249971 249974 250977 253977 256976 257973 258971 258969 0.50 528199 527193 524188 521183 518180 514176 510173 507170 504171 504175 506181 509186 512189 517194 519197 523202 526203 528199 0.50 513266 514261 513252 510245 509238 506233 502224 499214 496210 491209 486207 481208 473210 467214 461217 455217 454218 454222 459227 461229 460231 456234 453236 451238 453241 459242 468245 473248 478252 484259 488267 493274 501280 503280 506278 509272 511269 513266 0.50 498246 495244 493239 491234 489230 485228 483226 481222 475223 471223 468227 471230 474226 477226 480227 482234 485236 488235 491236 493239 495245 498246 0.50 496946 496945 493946 493947 496946 496946 0.50 348764 347760 345757 343758 340760 336767 330777 324787 318795 311802 302809 298812 299818 295827 292836 289846 289852 290858 294861 298862 301859 306853 315844 322837 324834 328829 331819 334808 337799 342789 345780 347770 348764 1.00 502271 501265 499261 495254 492246 490242 487240 482240 479235 477233 474233 471235 467234 464234 461238 465240 468240 469238 471239 473241 480247 485252 490261 494267 496270 500272 502271 1.00 505244 503236 499228 497218 494212 492213 488212 479211 476212 474215 481219 490223 493230 496238 501244 505244 1.00 335789 332788 328791 325797 320802 316807 311811 308814 307818 306824 302830 296840 295844 295848 296851 299851 306846 310841 321833 325827 328821 330806 334793 335789 1.50 489247 486246 489248 489247 1.50 326811 326807 325807 322809 320811 318814 317815 316816 315819 314821 314823 315826 316827 319827 321827 322827 322826 324823 324822 325819 326818 326814 326811 326811 24HR QP VT 12/12Z 0.01 556088 556068 556051 555011 554001 552996 550987 547982 540973 534965 527957 520953 513950 508948 502949 492954 486957 483961 482966 482975 484980 485988 489993 488997 487004 488011 488015 490019 490023 496036 500045 502049 505056 506059 500061 497066 494072 495082 496090 497100 497117 496122 492126 481125 476127 472128 464133 455139 451139 446141 444144 442150 442157 440163 435173 430186 426196 423206 422213 421221 420229 422231 425234 425236 422239 421242 424245 427247 432248 438249 443248 450245 454242 460242 463239 466243 468244 476251 481258 486267 488270 490278 493287 499292 505295 508292 512286 514278 517273 521260 517253 513241 510228 506219 501209 496204 491203 481199 481195 486192 494191 499192 505196 508198 513203 520211 524213 530218 533215 537211 539202 538191 533182 528174 523163 521157 520153 522141 527126 531113 532107 534104 537105 540102 543100 545105 549105 554096 556088 0.01 516823 513802 506781 503774 500769 498768 496766 494768 491772 485784 479798 476799 475798 476789 475784 470778 467773 469767 476755 479748 481740 484726 484717 481717 474722 470727 465731 461738 456743 452751 448763 444776 439791 436802 432815 430829 429838 430848 433856 433861 433865 429876 427884 429888 435887 439884 442883 444885 445890 444894 443902 443907 444918 446927 447932 452938 457940 463942 475942 482940 485939 492933 497927 501916 506902 508893 510886 512878 513869 515853 516836 516823 0.01 491234 489229 483225 477225 474225 468225 465228 462229 459227 453226 451230 452234 455235 458235 461237 461233 465230 470232 474229 479231 482236 485237 491234 0.01 367742 364733 363729 361726 357728 352732 343741 340746 333751 326755 321759 314767 297787 289795 281797 277797 264799 256803 253792 250787 244787 240791 238797 238808 237820 237826 238833 240836 243834 245830 250819 253816 257818 266825 267828 264834 260843 257849 256853 258861 261867 264870 268873 273874 282873 289871 295868 307867 312864 318860 324850 329841 335830 346809 354798 361788 366775 368764 368751 367742 0.01 417126 416107 416100 415097 410091 409084 404078 401075 398074 392079 387081 383076 380068 378064 375063 372064 370067 368075 364082 359086 355090 355096 358100 361102 364101 366098 371095 377100 382099 384102 385107 383111 378115 374119 372124 371130 371140 372144 368150 362154 360156 361158 363160 367166 370172 374175 378176 380172 381167 398147 401143 404141 407141 410138 413134 417126 0.01 304894 303891 299888 294886 291887 288888 285892 281896 280900 280903 282906 286907 292906 297904 300901 302897 304894 0.01 272970 271968 268965 264962 259961 254961 249963 241968 236973 234976 234982 235986 238990 244993 249994 255991 260987 265984 268983 269978 272974 272970 0.25 534014 533010 533009 531004 530003 528000 527998 525996 524995 521995 520996 521997 523001 524002 526005 527007 529010 530012 533014 534015 534014 0.25 513266 509255 507246 505238 503229 499219 497216 494215 491218 493222 494231 497241 500251 503257 507265 513266 0.25 518191 519184 518181 516175 514171 505158 499154 494148 490144 486143 481144 477146 472149 465153 458166 451167 449173 450179 455184 462180 466174 470173 474175 475177 480180 486178 494178 499179 503182 508187 514192 518191 0.25 500837 499833 495830 490831 487834 484840 482846 481851 480860 479872 479886 479890 483893 488891 491887 493881 495873 497862 499849 500837 0.25 504272 504268 501266 501265 501266 502271 503272 504272 0.25 356752 353748 348748 341752 338756 324776 312794 306803 302808 297812 288818 283822 279826 278831 283833 289843 298849 303849 307846 322827 334808 340800 346788 350778 354766 355758 356752 0.25 257979 256977 255976 253973 250973 249974 247975 245977 243980 242981 243982 243983 246985 248986 249986 251986 252985 254984 256982 256981 257979 0.50 497163 496161 493160 490160 489161 487162 485165 484169