FXUS04 KWBC 250743 QPFPFD QUANTITATIVE PRECIPITATION FORECAST DISCUSSION NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD 242 AM EST THU MAR 25 2004 PRELIM DAY 1 AND DAY 2 QPF DISCUSSION VALID MAR 26/1200 UTC THRU MAR 27/1200 UTC REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR DAY 1... OUTSIDE OF AREAS FROM NRN CA INTO THE PAC NW/NRN ROCKIES...THERE CONTS TO BE LOW CONFIDENCE WITH PCPN DETAILS DAY 1 IN THE MULTI STREAM FLOW ACRS THE NATION. NRN CA...PAC NW...NRN ROCKIES.... MODEL GUIDANCE IS IN FAIRLY GOOD AGRMNT WITH THE TIMING OF THE STRONG HT FALLS AND ASSOC FRONTAL BAND FCST TO MOVE INLAND INTO NRN CA NWD INTO THE PAC NW THU..AND THEN INLAND INTO THE GTBASIN/NRN ROCKIES THU AFTERNOON/NIGHT. IN THE WAKE OF THE PRIMARY FRONTAL BAND PCPN...SUSTAINED ONSHORE FLOW WL SUPPORT CONTINUED SHOWERY CONDITIONS FROM NRN CA NWD INTO THE PAC NW. THE ETA AND GFS WERE ALSO IN GOOD AGRMNT WITH TIMING OF SECONDARY VORT ROTATING INLAND LATE THU NIGHT/EARLY FRI MORNING OVR OR/NRN CA....WITH PCPN ENHANCEMENT EXPECTED AHEAD OF THIS FEATURE. OVERALL...THE STRENGTHENING ONSHORE FLOW AND INCREASING PWS WL SUPPORT WIDESPREAD HVY PCPN FROM NRN CA NWD INTO WA/OR TO THE WEST OF THE CASCADES AND OVR NRN ID. STRONGEST UPSLOPE COMPONENT TO THE ONSHORE FLOW WL BE ACRS NRN CA INTO THE SIERRA. HERE 1-2" PCPN AMTS ARE POSSIBLE UPR MS VALLEY/GTLKS... LESS CERTAINTY WITH THE FORECAST DETAILS DAY 1 ACRS THE UPR MS VALLEY INTO THE GTLKS WITH EXPECTED PCPN DEVELOPMENT AHEAD OF AT LEAST TWO STREAMS OF MID LEVEL SHRTWV ENERGY MOVG ENEWD FROM THE NRN AND CNTRL PLAINS INTO THE MID TO UPR MS VALLEY/GTLKS REGION AND AHEAD OF A SFC CDFNT SINKING SWD THRU THE UPR MS VALLEY INTO THE GTLKS REGION. THE MANUAL DAY 1 QPF PROG TOOK A BLEND BETWEEN THE ETA AND GFS HERE...DEPICTING POTENTIAL FOR PCPN DEVELOPMENT AHEAD OF EACH OF THESE STREAMS. INDIVIDUAL SREF MEMBERS FROM THE ETA AND RSM WERE SHOWING LARGE SPREAD IN SOLNS...ADDING TO THE LOW CONFIDENCE IN DETAILS HERE. WHILE CONFIDENCE IS LOW ON DETAILS...IT IS HIGHER WITH OVERALL PCPN POTENTIAL GIVEN MODEL SOLNS OF INCREASING MOIST SWLY LOW LEVEL FLOW AHEAD OF THESE HT FALLS AND SFC FRONT...WITH UVVS BEING ENHANCED BY WELL DEFINED UPR DIFFLUENCE ALONG THE SRN EDGE OF THE WLYS. DAY 1 QPF EMPHASIZED .50-1"+ PCPN AMTS ASSOC WITH THE MORE SRN STREAM OF SHRTWV ENRGY MOVG FROM NE...EWD INTO IA...NRN IL/SRN WI AND THE L.P. OF MI. THESE HT FALLS WL BE CLOSER TO THE SRN EDGE OF THE WLYS AND THE POTENTIAL FOR ENHANCED UVVS FROM UPR DIFFLUENCE MAX. .25-.50+ PCPN AMTS DEPICTED FARTHER TO THE NORTH OVR CNTRL TO ERN MN INTO WRN WI WITH THE FARTHER NWD STREAM OF MID LEVEL SHRTWV ENRGY. NRN MID ATL... WSWLY LOW LEVEL FLOW SHOULD CONT TO OVERRUN THE SFC FRONTAL BNDRY PRESENTLY STRETCHING FROM THE LOWER LAKES ESEWD INTO THE UPR OH RIVER VALLEY AND INTO THE MID ATL. DAY 1 MANUAL QPF WENT CLOSER TO THE GFS SOLN...DEPICTING .25"+ PCPN POTENTIAL FOR NERN PA/NRN NJ... AS IT APPEARS TO HAVE A BETTER HANDLE WITH ONGOING PCPN AREA. NRN NY/NEW ENGLAND.... PCPN ALSO EXPECTED TO SPREAD EWD INTO NRN NY AND NEW ENGLAND DAY 1 ASSOC WITH MID LEVEL SHRTWV ENERGY MOVG ACRS SRN QB/NRN NY/NEW ENGLAND. MODELS DEPICT .10-.25"+ PCPN POTENTIAL ACRS THESE AREAS. SRN PLAINS/LOWER MS VALLEY.... SIMILAR TO AREAS FARTHER TO THE NORTH...CONFIDENCE IS LOW WITH DETAILS OF PCPN IN THE SRN MOST STREAM ACRS THE U.S. ATTM...GIVEN LOW CONFIDENCE WENT WITH LIGHTER ETA AMTS...ALTHOUGH LOCALLY HEAVIER PCPN AMTS POSSIBLE FROM ERN TX INTO THE LOWER MS VALLEY AHEAD OF THE PRIMARY SRN STREAM VORT CURRENTLY PUSHING EWD. DAY 2... AN EXTENSIVE AREA OF PCPN IS EXPECTED FROM THE OH VALLEY NEWD INTO NEW ENGLAND AHEAD OF A FRONTAL SYSTEM PRESSING EWD IN ASSOCIATION WITH A NRN STREAM SHORTWAVE IN ERN CANADA. THE GFS IS WETTER THAN THE ETA...BUT FELT THAT A BLEND WOULD BE BEST HERE. IN THE NRN PLAINS...HERE TOO A BLEND WAS USED...BUT WEIGHTED MORE TOWARD THE ETA DUE TO THE GFS SHOWING GRID- SCALE FEEDBACK DURING THE FINAL 6 HRS OF THE PERIOD. IN THE WEST...AS MENTIONED IN THE PMDHMD THE ETA APPEARS TO BE TOO STRONG WITH THE SHORTWAVE COMING INTO THE NORTHWEST COAST BEHIND THE MAIN TROF AT THE END OF THE PERIOD. A CONSENSUS OF THE OTHER FCST MODELS IS MORE SUPPORTIVE OF THE BAGGINESS SEEN IN THE GFS OVER THE FOUR CORNERS REGION BY FHR 60. THUS MANUAL QPF LEANED STRONGLY TOWARD THE GFS. ORAVEC/MAUSSER GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV 24HR QP VT 26/12Z 0.01 488942 496855 495848 500763 495709 473662 461649 429646 414659 403672 393691 392702 389707 388713 384727 386741 391757 400794 402811 402823 398836 395844 391851 384859 382865 378871 363890 353899 347903 343905 339905 317907 310906 304907 299907 295907 293910 282928 280932 280941 279946 280953 281959 284966 287972 290977 299975 304971 308967 313962 317958 327953 331951 336950 343960 355966 356967 357972 359981 361985 365990 370990 375988 386981 391978 394978 396979 398983 400989 404993 407000 410008 419033 424044 428051 431052 435050 440050 447048 451046 454044 455041 455036 452029 444015 439002 437995 434988 432983 434979 438975 446970 470965 475963 479958 484953 487947 488942 0.01 529218 532205 534197 534190 533181 531178 528170 524162 519155 515147 512142 509140 498129 483123 474121 470118 462112 457098 447093 437091 424091 418100 414115 411129 406140 398148 395163 396178 402187 403194 397194 388190 370173 367176 363178 360178 348185 345195 346204 346211 347221 348231 352242 360252 372260 390269 411271 448265 483278 494291 499299 502302 506300 514278 518268 521255 522245 525235 529218 0.01 272803 269798 266796 262795 256795 249798 244802 242805 241809 241815 245821 248823 251822 255816 258812 263808 268807 271805 272803 0.25 466682 461676 455671 449670 443672 435677 432680 431684 432688 434690 439694 446697 452697 459695 463692 465688 466682 0.25 524197 524190 524184 520175 516167 510161 502155 497149 495144 492140 486134 480130 475129 472133 471137 473139 483141 485143 487148 487152 486154 481154 473150 468143 464141 459141 453146 450149 446148 443145 440141 438139 435141 433147 433154 435159 437162 443167 447175 446179 445181 442183 441186 443190 449195 453195 455191 460185 463182 465179 464176 457172 454168 455167 457165 459168 461170 463172 466172 469171 472171 475173 480180 486185 496189 505192 515198 521200 524197 0.25 510269 512262 514252 513245 512237 508225 504215 498205 495202 490200 486199 484200 481201 471204 462206 458207 454210 447213 437214 427215 419217 403205 395200 391198 387195 380189 371186 368187 366189 365192 361202 357213 355219 355226 355232 357236 360242 384256 406262 423257 433256 441255 452255 463257 474262 483268 491275 498283 503286 510269 0.25 463955 475932 480915 482898 479887 468894 459906 446921 438930 433926 438912 454894 467877 479852 476815 456812 430832 397861 393865 386874 373893 371899 384929 396938 408950 419958 443962 463955 0.25 419764 418756 416749 412743 410740 406736 403736 401740 401746 402753 405760 407767 410774 413780 415782 417780 419775 419768 419764 0.50 504276 506269 507260 509253 509243 508237 506231 502221 498212 492210 487209 482208 480208 474209 470210 454215 437218 432220 429223 427229 425230 419229 416226 414215 389198 381192 377190 372189 369191 370196 373205 374209 371211 365216 364222 364229 366237 373242 383246 388249 394250 404252 412253 421253 431253 440252 456252 467253 473256 478259 490271 497276 502278 504276 0.50 510179 510175 509173 504168 492162 479156 474154 471153 469149 465144 462145 457148 453155 449157 449160 452161 457159 460158 464161 468164 475166 483174 490178 498179 503182 507183 510179 0.50 491239 492235 491231 489225 487223 481221 477221 472222 469223 465226 468229 472228 477226 481231 485235 488235 490238 491239 0.50 471921 468918 463919 460920 455925 452927 450934 449940 452944 455943 460938 462934 465931 468927 471921 0.50 419852 394876 390882 384890 381898 382904 386905 390904 394904 398904 401908 403915 404921 405926 408933 413932 420925 428914 438899 457859 454847 450842 447839 441838 436840 431844 419852 0.50 459228 456226 453225 452226 453230 456229 459228 459228 0.50 463178 462177 459177 456178 455176 454175 452176 452180 450183 449183 450185 452187 456186 456185 459183 460182 462179 463178 1.00 497269 495267 494268 495268 497269 497269 1.00 470245 470240 465236 460233 452234 443236 441237 435237 428235 418233 416232 413227 413221 411218 407218 405221 403226 399226 391226 387227 385229 384234 384238 390243 399247 417249 424249 429249 432248 440245 448246 458246 465244 470245 1.00 463221 463220 460219 457219 460224 463222 463221 1.00 452222 451221 448220 448221 448222 451222 452222 1.00 436857 434856 431858 429859 429860 426864 425865 424867 422870 425872 428870 430867 432864 434862 435859 436857 1.00 412904 411913 415917 421916 424911 425897 425893 424890 423886 422886 421887 420890 419892 417895 417896 415900 415901 412904 1.00 404217 402211 400208 395204 392202 387199 384196 379193 376193 374195 377199 380202 383205 387209 390213 393215 398218 401218 404217 1.50 431244 430240 425237 419235 414233 409234 404235 399232 396232 395233 395237 397242 403245 408246 412246 417246 423247 426247 431244 1.50 398211 397209 396207 394206 392204 389203 387205 388206 391208 393210 394210 396212 398211 2.00 427243 427242 425239 422238 419237 419236 416235 415235 413238 412238 413239 415241 418243 421244 424244 427243 427243 24HR QP VT 27/12Z 0.01 521269 522260 523254 528235 523223 521218 522214 533214 540192 541184 538132 530094 528076 536070 546062 549045 546011 543991 545979 547962 542941 540935 525904 507902 505904 478914 466919 457917 448915 440912 436908 434903 429891 427883 428878 433870 435865 440861 449856 460851 464847 479847 488852 496865 503863 517822 524790 529741 522685 502647 487628 475616 457616 443633 442633 436643 430650 420661 414669 407679 398690 386708 372734 362754 360757 361763 362773 364781 364786 365794 364799 364809 363823 364832 363844 363857 364866 364871 362877 361885 360892 358901 354910 349919 342927 339931 333933 313937 307939 303942 297947 291954 287959 282967 280972 280976 282986 285996 289008 292013 295017 300018 306017 318010 331019 337025 341025 346024 349020 353017 360011 365009 370008 384009 391010 400012 411016 417018 418025 418035 417043 417048 414051 410052 405052 395055 384053 379052 373053 364054 361057 363061 364064 368073 378091 377103 377109 374115 371126 370135 373141 377143 381142 390138 396138 400142 401146 400151 402156 408159 410164 412169 414174 417180 418182 413188 407194 404197 400199 394206 391222 385232 386244 388249 391252 396254 400254 420261 436260 441259 449259 457262 466266 478272 493278 503286 509289 514286 0.01 321982 327975 331972 333967 331965 325967 322971 319974 315976 314980 315984 318986 321982 0.01 302814 301810 298807 294804 290799 283798 277797 273797 269799 270807 275812 280813 286816 292817 298816 302814 0.25 499776 510756 513733 497693 482660 471643 460642 445656 433672 428694 423703 416703 408705 401719 406726 417729 416741 412756 407774 402782 398789 392799 387810 380824 377833 378843 380850 380857 379867 378878 376890 373907 371917 368924 362931 358940 357962 354976 358983 366985 374979 378969 376958 376949 384935 393928 403920 407902 409880 410872 411862 412852 413842 416832 420827 423825 431824 437822 444819 452815 462808 471803 480796 488790 496781 499776 0.25 512271 513263 513252 512240 511232 505219 501211 495204 491200 488198 484199 471202 444207 420213 411219 407223 403229 400237 401243 404246 409249 416251 425253 439251 452251 467253 478256 483259 492266 502275 505277 512274 512271 0.25 521187 521182 519174 516167 514163 507156 498149 490146 480141 472136 467134 460133 452136 445142 441145 438148 436157 437162 447183 453184 458182 462178 465176 470175 474175 479177 487182 497189 505192 509193 514193 518190 521187 0.25 481030 504032 515039 524037 526020 521997 518983 516974 516967 516949 517940 518934 517927 512921 506918 501919 497922 490935 486943 480950 474955 469958 459962 451964 438968 430972 423977 420984 421988 424994 427997 431001 435007 437012 437018 440024 448027 454029 462030 470030 474029 481030 0.50 476678 472676 468676 463680 462686 461692 460697 458703 457708 461708 466704 470698 473696 476688 476683 476678 0.50 468744 476730 483719 477711 469721 461731 455738 450745 451751 451754 454756 460753 464749 468744 0.50 457677 451669 444672 441679 445686 450687 453685 457677 0.50 481771 480769 479768 477768 474769 471770 469773 466775 464777 464778 462782 461784 462788 464789 467789 470788 472786 475784 478782 480779 481776 481773 481771 0.50 501266 502261 501253 503243 503235 500225 498219 494212 492210 487207 481209 477212 468211 462211 458212 451217 447220 442221 434224 426229 411238 412242 417245 423246 426246 435245 446245 465245 476249 481251 488254 495260 501266 0.50 511942 511933 508929 506927 503926 500928 498931 488949 483960 481964 475968 467972 455975 446978 442982 439987 442002 443006 444011 446014 448016 454017 466015 474011 479007 483003 488996 491991 494983 497974 502963 506953 509948 511942 0.50 401870 402862 400855 396853 394853 392858 390863 389869 388875 387879 387886 390891 395888 398884 400880 401874 401870 1.00 479239 477237 476237 473237 475238 477239 479239 $$