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000 FXUS04 KWBC 092200 QPFPFD QUANTITATIVE PRECIPITATION FORECAST DISCUSSION NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD 559 PM EDT MON MAR 09 2009 FINAL DAY 1...DAY 2 AND DAY 3 QPF DISCUSSION VALID MAR 10/0000 UTC THRU MAR 13/0000 UTC REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR DAY 1... UPDATED...ONLY MININAL CHANGES WERE MADE BTWN THE PRELIM AND THE FINAL DAY1 QPF BASED ON LATEST MODEL AVAILABILITY AND/OR OBSERVATIONAL DATA. ...CNTRL PLAINS INTO THE SOUTHERN GREAT LAKES... ANOTHER ROUND OF LCLY HVY TO PSBLY EXCESSIVE RNFL IS EXPECTED FOR PTNS OF THE CNTRL PLAINS INTO THE SRN GREAT LAKES. THE 12Z SUITE OF MODEL GUIDANCE STILL SHOWED SOME SUBTLE DIFFERENCES WITH RESPECT TO TIMING OF INDIVIDUAL SHORTWAVES RIPPLING THROUGH THE SW FLOW ALOFT AND HOW THE WESTERN U.S. TROF DIGS INTO THE ROCKIES AND THEN STARTS TO HEAD EASTWARD...THERE IS OVERALL AGREEMENT THAT THE LOW/MID LEVEL FLOW WILL BE BACKING AND ACCELERATING WHICH ALLOWS FOR GOOD WARM ADVECTION AND MOISTURE TRANSPORT INTO THE AREA. MODELS STILL SHOW PRECIPITABLE WATER VALUES INCREASING AOA 1 INCH AND EVEN APPROACHING 1.25 INCHES DURING THE PERIOD AHEAD OF THE SYS, THE MODEL PCPN FORECASTS ARE NOT IN BAD AGREEMENT WITH THE AXIS OF PCPN AND AMOUNTS. THE NCEP MODELS TENDED TO DRAW A BIT MORE QPF NORTHWARD THAN THEIR EARLIER RUNS...AND WE FOLLOWED THAT IDEA GIVEN THE STRENGTH OF LOW LEVEL FLOW THAT DEVELOPS. THE GFS TENDS TO END UP WITH AN ELONGATED AXIS OF PCPN IN THE FINAL SIX HOURS OF OUR PERIOD...WHICH IS AN OUTLIER SOLN. CONSEQUENTLY...WE OPTED TO FOLLOW THE ECMWF SOLN HERE AND INDICATED A BAND OF 1-2+ INCH RNFL TOTALS..WITH SOME ISOLD 3 INCH AMTS PSBL. ...NEW ENG... LATEST MDL SOLNS ARE IN VRY GOOD AGREEMENT IN TAKING THE ERN GTLKS H5 S/WV GENLY OFF SHORE EARLY IN THE PERIOD...WITH DECREASING AREAL COVERAGE OF PCPN AS THE SYS MOVES AWAY. BASED ON RADAR IMAGERY...WE KEPT MORE AREAL COVERAGE THAN INDICATED BY THE MODELS...ALTHOUGH ADDITIONAL PCPN SHOULD ONLY AMOUNT TO A TENTH TO A QUARTER OF AN INCH. ...WRN STATES... THE REGIME OVR THE WRN STATES WL BE DOMINATED BY THE H5 TROF DIGGING SSEWD FM THE PAC NW/NRN GT BASIN INTO THE CNTRL SRN ROCKIES BY THE END OF THE PD..WITH THE 12Z SUITE OF MODEL GUIDANCE BEING IN GOOD AGREEMENT WITH EACH OTHER AND MAINTAINING GOOD RUN TO RUN CONSISTENCY. MID LVL HGT FALLS/DYNAMICS AND LRG SCALE LIFT WL RESULT IN WIDESPREAD PCPN..MSTLY SNOW..THRUOUT THE CNTRL GT BASIN AND ROCKIES. ALTHO MSTR NOT THAT GREAT..STG LIFT AND OROGRAPHIC ENHANCEMENT WL SUPPORT SOME MDTLY HVY SNOWS. OUR MODEL PREFFERENCE LARGELY REMAINED THE ECMWF WITH SOME ENHANCEMENT IN THE COMPLEX TERRAIN AS SHOWN BY THE 12 KM NAM. DAY 2... THREE AREAS OF MDT TO HVY QPF AMOUNTS IS EXPECTED WED INTO THURS MORNING... MAINLY INVOLVING THE DYNAMIC PHASING POLAR SHORT WAVE WHICH LIFTS FROM THE UPR MS VLY/GRT LAKES INTO ERN CANADA. ...UPR MS VLY... THE DYNAMIC POLAR SHORT WAVE ROLLING THROUGH THE UPR MS VLY WILL CAPITALIZE ON THE DEEP PLUME OF LL MOISTURE SURGING NORTH FROM THE GULF OF MEXICO AND PRODUCE HVY SNOWFALL ACROSS NRN MN/WI AND THE UP OF MI. THIS MOISTURE WILL FLOURISH IN THE COMA HEAD OF THE DEEPENING AREA OF LOW PRESSURE WHERE IMPRESSIVE VERTICAL LIFT WILL BE PRESENT. THE MODEL GUIDANCE VARIES A BIT ON HOW MUCH QPF AND HOW QUICKLY THE SYSTEM LIFTS OUT OF THE REGION. THE ECMWF IS QUICKER THAN THE NAM/GFS... WHILE THE 09Z SREF MEAN SEEMED LIKE THE PERFECT COMPROMISE OF ANOTHER .25 TO .50 INCH LIQUID OR SNOW. ...OH VLY TO NORTHEAST... THE IMPRESSIVE COLD FRONT ACCOMPANYING THE POTENT SHORT WAVE WILL PLOW THROUGH THE OH VLY/GRT LAKES AND PUSH OFF THE NERN/MID-ATL SEABOARD OVER THE 24 HR FCST PERIOD. MOST OF THE MODELS INDICATE THE HEAVIEST RAINFALL TO OCCUR IN THE VICINITY OF THE TRIPLE POINT LOW TRACK FROM IN THROUGH SRN LWR MI/NRN OH INTO THE INTERIOR NORTHEAST. THIS IS WHERE THE POWERFUL JET DYNAMICS WILL CAPITALIZE ON THE POOLING LL MOISTURE. EXPECT A SOLID 1 TO 1.75 INCHES FROM SERN LWR MI INTO CENTRAL NY STATE WITH SLIGHTLY LIGHTER AMOUNTS ACROSS THE REST OF THE NERN SECTION OF THE COUNTRY. ...SRN PLAINS/LWR MS VLY... THE FINAL AREA FOR HVY PRECIP ON D2 WILL BE IN VICINITY OR JUST NORTH AND ALONG THE POLAR COLD FRONT WHICH WILL DIVE DOWN THROUGH THIS REGION TOWARD THE GULF OF MEXICO. THE MODEL GUIDANCE INDICATES ENOUGH OF A SRN STREAM TROUGH PRESENT OVER THE SW INTO MEXICO AND SWRLY FLOW INTO THE SRN PLAINS TO INTERACT WITH A SIGNIFICANT AMOUNT OF GULF MOISTURE EXPECTED TO OVERRUN INTO THE COLD SECTOR FOR ORGANIZED HVY RAINFALL. HPC GENERALLY FOLLOWED A BLEND OF THE ECMWF WITH THE NAM ON THE AXIS AND AMOUNTS OF HVY RAIN FROM SERN MO/WRN TN/KY SWWRD THROUGH AR INTO NRN LA AND MUCH OF EAST AND CENTRAL TX... WHERE 1 TO 2.5 INCHES IS POSSIBLE. DAY 3... ...SOUTHERN PLAINS/LOWER MISSISSIPPI AND TENNESSEE VALLEYS PREVIOUSLY NOTED POLAR FRONT IS FORECAST TO STALL OVER THE GULF COAST... AS MORE SRN STREAM DYNAMICS APPROACH TX AND THE LWR MS VLY. EXPECT HVY RAINFALL/CONVECTION TO DEVELOP FROM THE TX HILL AND BIG BEND COUNTRY THRU THE ARKLATEX AND INTO THE TN VLY. DEEP GULF OF MEXICO MOISTURE AND HIGH PWS WILL CONTINUE TO OVERRUN THIS BOUNDARY INTO THE COLD SECTOR AND INTERACT WITH THE MODEST UPPER DYNAMICS AND ENHANCED VERTICAL LIFT. AREAL AVGS OF ANYWHERE FROM 1-3 INCHES CAN BE EXPECTED ACROSS THIS REGION. HPC LEANED MORE CLOSELY TOWARD THE CONSISTENT ECMWF ACROSS THIS REGION. THE NAM AND GFS ARE SLOWER AND HOLDING BACK THESE SRN STREAM DYNAMICS THAN THE ECMWF... WHICH PARTIALLY HALT THE MOISTURE FROM SPREADING DOWNSTREAM ACROSS THIS REGION. NEEDLESS TO SAY... EXPECT VERY HVY RAINFALL FROM SOUTH CENTRAL TX TO NERN TX INTO AR/NRN LA AND INTO WRN TN/NRN MS WITH EVEN SOME MIXED PRECIP BACK OVER WEST TX AND THE NRN FRINGE OF THE PRECIP SHIELD. BANN/MUSHER GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV 24HR QP VT 11/00Z 0.01 527868 527855 526850 524845 522840 514840 509842 505845 495854 486864 480868 473870 465858 461852 458846 453832 452828 453824 454819 458809 460798 457782 455773 452766 449759 445754 438748 429741 419736 410732 404732 399734 395738 393743 391749 391756 391784 391796 390808 390819 390824 387829 381836 379842 378848 378858 378871 376882 374888 371894 363904 357913 350922 345931 338940 331948 320963 309978 304985 303989 304996 308001 303007 299017 300024 304027 307026 315024 322018 340003 350998 359993 383989 388987 392985 396982 400979 406973 408972 409979 409987 408992 406003 405011 404019 406025 409030 412034 411039 406045 403049 399051 387057 376058 371056 365056 361058 358059 357063 377113 366118 359124 358128 358132 361136 365140 369145 372148 380151 388152 392150 392148 392146 388140 388136 390134 396132 418129 421132 422139 428133 433125 436123 440124 452127 427184 425188 425191 428192 434188 443203 451198 455196 458190 461186 465184 471184 478188 481193 482197 481202 478206 472207 468210 461210 456212 451213 444213 432215 424220 416231 404240 404243 407246 414247 420250 430250 439250 448250 461250 473251 477250 480249 481246 480238 479234 476231 477225 482223 488220 493219 498215 498205 502198 505192 508190 511190 515186 517180 516174 514169 514165 515161 515156 515150 514145 512132 506116 500105 493099 488097 482097 478098 475095 473089 470087 467088 464086 464082 479061 485050 490037 493022 495011 496003 500976 505952 509941 514927 523899 526881 527868 0.01 330048 330045 330042 329040 328038 326036 324036 321036 318038 317039 316042 317045 318047 320049 321049 324050 327052 330049 330048 0.01 303052 303048 300046 296046 288052 281053 277055 273059 271062 272072 267084 268088 270090 274092 282092 285090 290086 294082 296077 298072 301059 303052 0.25 496923 497911 497906 495901 493899 489898 484899 472907 466910 460911 447914 441915 438913 437910 437906 439901 442892 442886 441882 438873 435853 434839 433822 432807 431799 429792 424780 417770 414765 412763 411765 407776 405782 404789 403804 403816 402826 400839 396848 393860 390872 384898 381907 378916 369936 360956 358963 358970 359972 363971 369969 382966 389963 397958 406953 412949 416946 419942 422939 424935 425929 427932 427940 428948 435972 439984 443995 446000 448009 448012 446019 440030 437036 434043 432048 427051 424053 421056 418060 416060 412061 404060 398060 393063 389065 384070 381071 377069 375068 374071 374076 376082 384086 395090 401088 405092 407095 409099 406100 405108 405111 408113 410110 410105 409100 410095 415080 419077 424076 427076 433078 435079 438076 441072 446064 450055 456043 460026 461019 463012 469000 474990 478977 482966 486957 491947 494937 496923 0.25 483165 481163 480160 479158 476156 474154 473153 471151 468149 465153 465157 467161 467162 469164 472166 475166 478167 481166 483165 0.25 450221 448220 445220 445223 448223 450221 0.25 398117 399113 397112 394112 394113 391114 388115 386116 385117 383119 385123 388122 390120 391119 394117 397117 398117 0.50 483931 483921 481918 472922 466924 461927 458930 455934 455939 454942 452944 451953 453960 457969 461973 463975 463979 466971 471960 476952 481941 483931 0.50 427815 426808 424801 419793 414790 412790 410792 409795 408806 407816 405833 403842 401851 397864 391882 387898 383916 378930 375938 373947 370955 370959 372962 382959 389957 396952 400947 406941 410933 416920 425905 428897 431889 433880 431867 428854 427844 428827 427815 0.50 414072 412069 412068 410066 407066 404066 401067 400068 398070 395072 392071 391072 389075 389076 391079 392080 395083 398083 401081 404080 406080 407079 409076 410075 412074 414072 1.00 418827 418823 415822 412827 411838 411846 409852 405861 397883 394896 390908 385932 381944 380948 382952 389950 393948 398944 401940 406931 410921 415909 418896 421883 420871 418862 416853 417847 417840 418827 1.50 417884 417879 416874 415869 412866 407867 404873 401884 399890 397898 394911 392923 390930 389938 392942 395941 398939 402933 405927 409914 412902 416889 417884 2.00 414877 412873 410871 407874 406880 402889 400899 398910 395922 394934 398935 400932 402928 404918 408907 410898 413887 414877 24HR QP VT 12/00Z 0.01 495666 493658 490655 482654 468650 455646 448645 443647 417660 413663 411666 408673 403679 397681 387684 383686 383689 383697 386710 390719 389726 389733 387737 383743 379747 376754 373770 370785 367797 360814 353828 341855 330879 319903 292956 290960 290965 290971 286978 284981 275990 271994 269998 266007 265013 267018 272032 274035 274040 273047 278052 283053 293059 298063 300070 301079 303086 305092 313093 323095 330097 337100 339098 341095 342090 342085 338080 328068 320060 316055 316049 316042 318036 320035 326025 331018 337012 344997 355970 360963 365958 368954 370953 373950 377945 381940 391930 404916 410910 417906 421904 425904 432908 436914 440922 444933 446941 448950 450960 452968 455978 459985 464992 471996 476997 481997 486995 490992 497987 501981 506973 514955 521941 527923 531906 534885 535870 535862 535857 533842 530826 527812 523804 512781 508774 503767 500762 498757 498753 501743 502734 501728 501722 500714 496706 495701 497696 499693 499685 496672 495666 0.01 470111 472106 471101 472092 470087 465085 462081 460075 457064 451055 444050 441049 438050 434053 431057 431060 432064 434069 434073 437075 439073 442075 444077 450084 448089 444092 438090 432091 428088 425088 427094 430099 429104 426104 423105 422108 424112 432111 437112 441115 452117 459110 467111 470111 0.25 521851 519838 517831 513822 509817 505811 500807 496806 490805 485812 482819 474831 471837 469844 465858 462873 459886 457895 457901 458911 460918 463927 466933 474942 478946 482947 485947 492945 497941 502935 505929 510917 516900 519886 521876 522868 521851 0.25 458683 457678 454675 451670 442665 436664 432666 422672 417677 414682 412692 403711 403723 404738 404743 407752 410759 412766 412773 411778 407787 404797 403806 396817 393829 379845 375849 374849 371845 370835 365838 362851 354872 350881 345889 326920 319929 314937 309946 306955 300972 296980 292986 286997 285001 284008 283012 280016 279019 281022 285024 294026 299026 302024 314011 321002 326994 331984 336977 347965 354958 360952 367943 374934 379925 385917 411890 415884 417878 419872 423867 427863 430858 436850 438845 439838 440829 441823 444818 449808 453802 456796 459784 462771 463758 460745 460736 460731 462720 462709 459693 458683 0.50 514864 514854 512847 508838 505833 502829 499827 495826 487829 484835 475853 470873 468886 468896 469904 470910 475916 478919 483921 486922 490920 497914 501907 506897 509889 513876 514864 514864 0.50 447682 440677 435675 432675 426677 423683 421693 422699 420704 416712 415721 413730 413738 413745 417760 419772 418777 416782 414791 413800 413810 412822 412828 413836 412844 407852 401850 396855 393858 389863 383872 380866 376867 372870 366878 360884 353891 342905 334917 322933 314950 307965 300979 295986 291995 290999 291003 294014 296016 301015 306009 312004 316000 321989 326982 332974 337968 348957 357942 359937 363934 372929 377921 382913 390896 395890 401885 407882 411878 418869 423861 427852 429842 433832 441817 445804 448792 449781 450769 450757 449748 445734 446722 446715 446710 444703 445698 447690 447682 1.00 438753 437747 435743 433741 430742 427744 425748 422754 423760 426764 429774 428781 421792 420798 420806 421822 423826 426827 430826 434821 437816 440804 443790 443781 442773 437763 438756 438753 1.00 420847 419843 417848 415853 416855 418852 420847 420847 1.00 353925 351918 349915 345915 340918 337921 333927 326935 322942 318951 315960 312968 307975 303983 298990 297993 297996 300998 308997 312993 314989 318983 327968 336952 341943 346937 351935 353930 353925 1.50 435806 438791 438783 434792 429799 426807 426809 426811 426815 428819 429818 431816 433812 434807 435806 1.50 343928 343924 341924 338928 335930 331934 326941 322949 319956 317961 317967 311974 306983 310985 321968 326961 331954 335946 339935 343928 2.00 333943 333940 331938 329941 327945 325948 327951 328952 328951 330950 332947 332945 333943 2.00 321963 322959 320959 320963 321963 321963 24HR QP VT 13/00Z 0.01 489656 487649 483642 475634 469629 463624 455622 451621 445622 435627 425634 419640 415645 406657 398667 390681 379702 374712 368721 367725 364728 358736 350751 345760 342769 343775 346778 350781 353788 354794 354802 352809 352816 353822 354831 353838 350844 348846 345851 339859 328860 325860 323863 322868 321878 319882 316885 310884 305886 302887 295893 293897 292903 291915 290925 286937 282947 277954 270963 260968 250973 248978 248981 249985 252989 256996 259005 263012 268017 271020 273025 277033 282041 288047 299053 310057 319063 322066 329065 333064 337066 340070 345072 347074 343076 339074 333073 328075 325078 324081 323088 325096 329104 333110 340116 354131 359135 364139 368144 371150 370158 367163 362167 359167 354162 348160 345160 343161 338162 332162 326160 322161 323165 322168 320170 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448861 0.01 339776 338774 336775 331779 324787 320793 314802 310807 307812 307815 310817 313818 319816 326810 329802 334793 338784 339776 0.01 361114 361111 360108 360107 358103 358102 356100 355099 352096 349094 347092 346092 346095 347096 348099 349103 349104 350106 352108 353110 354111 357114 360114 361114 0.25 370859 369852 367846 363844 358847 355850 353854 350866 344874 340882 337887 334891 327898 321903 313910 299924 296930 293941 291952 290957 288962 285968 279975 265987 263993 266996 271003 276011 278016 284018 293015 305014 314012 319009 323006 327999 334991 340985 347975 351969 354959 357949 360936 361927 364916 366904 367898 366890 370859 0.50 365868 365861 363856 361855 358857 356861 352871 347879 338894 332902 326908 320913 315921 313925 309928 302930 300937 300941 301947 302953 303958 303962 301966 297967 292968 287970 285973 280979 272986 268992 269995 272997 277004 280008 286009 306006 312004 316002 321993 325988 332983 339977 346968 349962 352953 355942 357931 361912 363901 363890 363883 364877 365868 1.00 355907 354902 350897 345899 340905 333915 328919 324925 324932 319946 318951 314957 314963 311971 307974 302975 290977 281983 277989 277993 279997 288003 294004 302002 310995 315990 320986 328979 338970 344962 347954 349947 353936 355928 355921 355907 1.50 351929 351923 351919 349915 347915 343915 340918 333926 328935 324945 321956 317963 314969 311974 305978 298981 292981 287983 284985 281989 282994 291999 294999 299996 315986 323980 330972 335966 339960 341956 348936 351929 2.00 342931 342928 340927 336932 334936 330941 327945 325952 321963 316971 308979 307981 309984 314983 318981 322978 329968 334959 338948 342935 342931 2.00 297992 298989 295987 294986 292985 290985 287986 285987 284989 284991 285991 288993 290994 293995 296993 297992 $$