QUANTITATIVE PRECIPITATION FORECAST

 
 FXUS04 KWBC 242148
 QPFPFD
  
 QUANTITATIVE PRECIPITATION FORECAST DISCUSSION
 NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
 447 PM EST TUE NOV 24 2009
  
  
 FINAL DAY 1...DAY 2 AND DAY 3 QPF DISCUSSION
 VALID NOV 25/0000 UTC THRU NOV 28/0000 UTC
 REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR
  
  
 DAY 1...
 
 UPDATED...ADJUSTED FORECAST OVR FL TO REFLECT PSN OF CDFNT TMW
 AFTN AND EVNG..WHILE ANTICIPATING A SECOND AREA OF SHWRS ACROSS
 SRN FL EARLIER IN THE PD WHEN SOME FVBL SRN STREAM JET DYNAMICS
 COULD ENHANCE THE LIFTING PROCESS.  OTHERWISE...CHANGES MADE FM
 THE PRELIM TO THE FINAL DAY1 WERE MINOR AND BASED PRIMARILY ON
 CURRENT OBSERVATIONAL DATA. 
 
 ...GTLKS/OH VLY...
 THE LATEST MDL SOLNS CONT TO BE IN VRY GOOD AGREEMENT IN THEIR
 HANDLING OF THE CLOSED LOW OVR THE MID MS VLY ATTM..WITH ALL
 LIFTING IT MORE QUICKLY ENEWD THRU THE GTLKS DURG THE PD AS THE
 UPSTREAM SYS NOW VCNTY OF ALTA/SASK DIGS INTO THE MIDWEST BY WED
 EVE.  NEITHER OF THESE SYSTEMS WL HAVE A LOT OF MSTR TO WORK
 WITH..AND THE GULF OF MEX WL RMN CUT-OFF..BUT STG MID/UPR LVL
 FORCING SHLD COMPENSATE FOR THE MARGINAL MSTR TO SUPPORT AN AREA
 OF LGT TO MDT PCPN FM THE MIDWEST ENEWD THRU THE
 GTLKS..PREDOMINATELY ON THE N AND E SIDES OF THE FEATURES.  AS
 PREVIOUS FCSTR DID..TOOK A BLEND OF NAM/GFS/GFSP QPF SOLNS GIVEN
 VRY SIMILAR MASS FIELD SOLNS.
 
 
 ...PAC NW...
 POWERFUL ERN PAC/SRN GULF OF AK STORM SYS WL MAKE STEADY EWD
 PROGRESS THIS PD..FINALLY PUSHING THE ASSOCTD CDFNT INTO THE PAC
 NW TWDS THE END OF THE PD.  LONGER DURATION OF STG LOW LVL ONSHORE
 FLOW AND HVIEST PCPN WL RMN N OF THE U.S. INTO B.C..BUT UP TO
 40KTS OF SWLY H85 FLO FINALLY MAKING IT INTO NWRN WA LTR WED MRNG
 FOLLOWED BY PASSAGE OF CDFNT LTR IN THE AFTN SHLD SUPPORT
 INCREASING PCPN OVR NWRN WA..AND ESP OVR THE OLYMPICS..WHERE SOME
 GTR THAN 1 INCH WTR EQUIVALENTS ARE LIKELY.  MDL QPFS WERE FAIRLY
 SIMILAR..BUT DID LEAN TWDS THE SLGTLY HVIER NAM AMTS A LTL FARTHER
 S ALG THE WA CST AS COMPARED TO THE GFS.
 
 
 ...FL...
 STILL QUITE A FEW PROBS HERE BTWN THE MDL QPFS..AS MDLS SEEM TO BE
 HAVING TRBL HANDLING SRN BRANCH S/WV ENERGY MOVG THRU THE FL PENIN
 WHICH RESULTS IN SIGNIFICANT QPF DIFFS.  IN ADDITION..IT APPEARS
 THE GFS IS SUFFERING FM FEEDBACK PROBS..MAKING ITS QPF SOLN
 SUSPECT AT BEST.  THIS IS NOT A VRY HI CONFIDENCE FCST..BUT WL
 LEAN TWDS THE NAM SOLN ATTM..WITH INCREASING CNVCTN DVLPG ERY IN
 PD N OF OLD FNTL BNDRY WHERE SRN BRANCH S/WV ENERGY WL ALSO BE
 MOVG THRU..AND WITH CNVCTN LTR IN THE PD ENHANCED BY SEWD MOVG
 CDFNT ASSOCTD WITH SOME HGT FALLS FM NRN STREAM ENERGY MOVG THRU
 THE ERN STATES.  SOME REASONABLY HI PWS WL BE IN PLACE..AOA 1.75
 INCHES..SO SOME BRIEFLY INTENSE RNFL RATES ARE LIKELY..AS ARE SOME
 LCLY HVY RNFL AMTS THIS PD..MAINLY OVR NRN AND CNTRL PTNS OF THE
 FL PENIN.  WENT CLOSE TO THE NAM LOCATION OF THE HVIER RAINS..BUT
 DIDN`T GO QUITE AS HVY AS IT..AND AGAIN GAVE VRY LTL WEIGHT TO THE
 GFS SOLN GIVEN ITS POTNL FEEDBACK PROBS.
  
  
 DAYS 2/3...
 
 ...PAC NORTHWEST/NRN CA THROUGH NRN ROCKIES...  
   
 THE MODELS STILL AGREE THAT A POTENT SYS WILL BE MAKING ITS WAY
 FROM THE ERN NOPAC INTO THE PAC NW ON DAYS 2 AND 3. MODELS ARE
 STILL QUITE DISPARATE...BUT H5 PHASING/SFC LOW INTENSITY SEEMS TO
 BE CLUSTERING AROUND THE 12Z ECMWF WHICH MADE MADE A FAVORABLE
 ADJUSTMENT TOWARDS ITS OWN ENS MEAN...SO HPC CHOSE TO USE THAT
 QPF.  REGARDLESS OF WHICH SOLN VERIFIES...THE PERSISTENT/STRONG
 MSTR FETCH SHOULD WILL FOSTER 2-3 INCH AMTS IN THE WA COASTAL
 RANGE AND CASCADES...AND AN INCH IN THE LWR ELEVATIONS OF WRN WA. 
     
 
 ...GTLKS REGION AND NORTHEAST...
 
 TROF AMPLIFYING INTO THE MS VLY WILL SLOWLY SLIDE EAST THROUGH THE
 PD...WHILE THE ORIGINAL SFC LOW DRIFTS THROUGH THE GTLKS.  MSTR IS
 NOT IMPRESSIVE...BUT THE PERSISTENT DYNAMICS WILL FOSTER
 INSTABILITY SHWRS AND WRAP AROUND/DEFORMATION PRECIP CENTERED ON
 WI/UPR MI...AND ALSO DOWNWIND OF THE LAKES AS THE SYSTEM PULLS
 EWD.  GENERALLY 0.50-0.75 INCH IS EXPECTED MAINLY ON DAY 2
 HERE...SIMILAR TO THE 12Z NAM/ECMWF DEPICTION.  
 
 MEANWHILE...AN INITIALLY WEAK SFC LOW MOVING UP THE ATL COAST WILL
 DEEPEN SHARPLY THURSDAY EVNG IN RESPONSE TO THE APPROACHING UPR
 TROF.  THE LOW WILL WRAP SIGNIFICANT MSTR WWD INTO THE NEW ENGLAND
 ON DAY 3.  CONSIDERABLE TIMING/TRACK/INTENSITY SPREAD EXISTS WITH
 THIS SYSTEM...AND THE PMDHMD SUGGESTS A BLEND OF THE 12Z
 NAM/ECMWF/GEFS MEAN.  UNFORTUNATELY EACH OF THOSE INCLUDED A
 SUSPICIOUSLY-CONCENTRATED AREA OF PRECIP...SO HPC CHOSE TO
 FORECAST USING ENSEMBLE QPF HERE. THIS RESULTED IN A SWATH OF
 0.50-1 INCH FROM NRN PA TO ME...AND AN AXIS OF OVER AN INCH IN
 NH/ME.        
 
 TERRY/SOWKO  
 
 GRAPHICS AVAILABLE ON THE WEB AT WWW.HPC.NCEP.NOAA.GOV
 24HR QP VT 26/00Z
  0.01 524251 508215 507212 508209 510207 515209 517214 520219 
       524222 530222 534220 536217 537210 534198 530188 524180 
       518174 510169 506166 501164 495165 493167 493171 495176 
       498179 503182 505187 505192 504195 501201 496204 492201 
       486201 481204 477205 474207 471212 472219 474220 477219 
       481221 481226 477227 469231 462233 461240 459246 457249 
       454256 446275 447284 452294 458301 469306 470315 473319 
       478320 484318 492313 499308 510299 
  0.01 498828 495811 491798 484781 481776 477772 473768 468765 
       460761 451758 447756 449750 453742 453734 448733 445735 
       433744 427747 422746 414744 404746 392751 389753 384753 
       376752 370751 365754 362758 365763 371770 382777 381784 
       379787 377792 377799 384794 389790 392787 398781 404779 
       409780 415777 418775 420776 421781 414785 410787 408790 
       406793 406799 403804 397806 388813 385817 385823 385827 
       383829 377833 369839 359845 349853 342860 338862 335867 
       335877 333881 330884 329890 330893 336894 339894 352890 
       359889 366888 384887 390889 393892 394895 395903 396916 
       399924 402929 409937 416944 424950 429953 430957 434969 
       437974 440978 449986 447991 444993 443996 443001 444005 
       448010 451016 455020 461021 467017 470016 474016 481023 
       484024 487022 492018 498015 502011 504006 504996 503990 
       494978 489969 482962 478958 476951 477934 478931 481928 
       485926 494918 500913 503908 506902 508895 506890 503886 
       499884 497880 498876 499866 500852 498828 
  0.01 494149 492144 489140 486136 480135 478133 472132 469136 
       468138 471142 474141 480141 484143 486147 488150 491150 
       494149 
  0.01 470111 470106 468106 469111 470111 470111 
  0.01 470094 470093 467093 467094 470094 470094 
  0.01 460085 461078 460072 458064 456060 453057 450056 448052 
       446043 443043 440044 439049 437052 434055 434057 436059 
       441064 445068 447080 450085 459087 460085 
  0.01 355752 355749 354747 352747 342752 328762 313772 297779 
       288780 281783 273784 269781 266781 260782 252786 242796 
       238803 236811 236818 237826 239835 241841 244845 248849 
       254853 261854 269854 273858 281859 287855 292848 301837 
       313826 318820 324813 331800 334792 338784 348771 352765 
       355756 355752 
  0.01 263960 261956 256955 251957 247959 241964 236970 234979 
       234985 236990 239996 245002 253005 257003 258997 257988 
       258975 260968 263960 
  0.25 524261 521253 517243 510229 505221 500215 496213 491213 
       488217 487224 485233 481234 476232 471236 467244 465249 
       466256 471261 474264 470276 470281 473285 476287 478290 
       483295 487299 491300 498299 504296 511292 
  0.25 474804 472796 468792 465791 459792 457797 458803 460808 
       461813 460817 459820 457821 451826 447834 443840 434844 
       427847 418851 412854 406860 404863 404868 408875 412881 
       414893 416912 419919 422922 425923 431927 436931 441934 
       450934 458930 463924 466918 466914 462912 458908 454901 
       455893 458886 466871 470854 472846 473836 472825 471817 
       474809 474804 
  0.25 315798 313793 310790 306788 301788 282794 278794 273793 
       266790 258793 251797 246804 243812 242820 244827 257838 
       261839 265839 273839 278839 284836 291831 298824 305819 
       309815 311811 314802 315798 
  0.50 522265 521258 518251 511237 504225 500220 497219 493219 
       491221 489227 488234 485237 483237 476234 472240 470244 
       470249 474253 476255 478261 477267 477273 478277 485287 
       491292 499293 509289 516283 
  0.50 444875 442867 438867 437870 431875 428884 427886 426881 
       427879 427873 425869 421867 421868 423871 423874 423880 
       422885 420893 420903 423910 429913 436917 442920 446919 
       449915 446907 443904 440902 438900 437894 443879 444875 
  0.50 309808 308803 306799 300795 289796 281798 274799 268798 
       266796 262796 255799 251803 247810 247816 248820 251824 
       255826 260830 262833 266835 271833 277830 284827 291822 
       304815 307811 309808 
  1.00 518273 519268 520264 518255 511241 503230 500226 496225 
       494226 492237 491239 487240 482243 479237 476239 477243 
       479245 481249 482257 482267 484273 489279 493283 500287 
       506286 510282 515278 518273 
  1.00 300808 294804 290802 285801 280804 274809 271813 268821 
       269826 275821 281817 285817 291813 295812 299810 300808 
  1.50 516272 518265 517259 515252 510244 506236 500231 497231 
       496236 496240 494242 492244 486246 484253 485256 486265 
       487270 490274 495280 500283 504284 509279 512275 515273 
       516272 
  2.00 516267 515257 512250 508242 503237 499238 499244 498248 
       489246 487249 487255 489265 491271 497278 500281 504281 
       508276 514271 516267 
  3.00 512266 513261 512256 509250 507248 504253 502257 497255 
       494252 490252 490259 492266 494270 497273 502278 505276 
       506273 508268 512266 
  4.00 503271 502266 501264 499261 498260 496258 493258 493259 
       493262 495267 496268 497270 500272 503271  
  
 24HR QP VT 27/00Z
  0.01 540207 540202 537196 532185 529179 525175 519168 504155 
       501152 499150 496152 491162 490170 488174 486179 482182 
       479196 477203 474207 467211 464214 459215 448225 443227 
       439230 434237 431236 427232 417229 401236 397237 396242 
       398253 399264 400269 402274 404283 410289 419294 428296 
       433297 437297 445295 453291 460285 472272 478266 482263 
       485264 493269 499276 503281 505284 509284 512280 516281 
       523257 521253 519247 517239 515234 513228 510223 508218 
       506213 503207 504202 507201 511203 515208 518211 523216 
       526219 531222 535220 538213 
  0.01 476683 473676 470670 465668 457664 450664 441666 437673 
       434679 432681 424684 415690 411694 408699 407703 407707 
       409711 413713 419716 425717 435714 439711 440708 443706 
       448705 455701 460700 462703 466706 470706 474701 476697 
       476687 476683 
  0.01 503782 502770 500764 498758 493748 489742 485737 481735 
       471730 465728 459728 455730 452733 444737 435734 430734 
       429741 426748 419753 415754 413747 404740 400738 395740 
       390744 383748 380750 377753 376756 377759 380761 400763 
       403764 404766 401773 400775 401780 400787 397793 395798 
       392811 392819 392829 395838 395846 396855 394861 393866 
       392873 391878 392883 394889 396892 399900 401910 403916 
       405922 409928 411930 415932 423940 428941 432942 437941 
       442938 447935 458925 467916 476905 479900 481896 482892 
       480887 478883 475876 475866 475862 477857 486844 493834 
       496828 498819 499808 499795 503782 
  0.01 362752 361747 358742 351740 345739 338740 331742 322745 
       316747 311751 297761 290765 282769 266773 256778 249784 
       246789 243796 239801 237807 236814 239822 243827 249829 
       254825 258819 263814 270814 276818 282820 288822 293821 
       296817 302811 306805 311802 317796 322790 327785 335781 
       343776 346773 349771 357765 360758 362752 
  0.01 305084 304074 302072 296069 294066 293061 294052 294046 
       296040 296037 295034 285031 276028 270026 267026 263029 
       257027 251029 249031 248036 248042 249049 252057 257063 
       259066 260068 260072 259078 261082 266089 269091 275093 
       285093 291092 296091 299090 304088 305084 
  0.25 520269 519264 517260 514258 511261 512265 513268 515270 
       518271 520269 
  0.25 526198 526193 523188 522187 520186 518186 517186 516190 
       517192 520195 522197 525198 526198 
  0.25 507244 504228 502222 499216 496200 498191 500185 504178 
       503174 502170 499169 496176 494184 491189 488196 485201 
       477209 470218 462225 459230 455232 449234 446238 444245 
       438258 436266 439272 443275 449276 457274 467267 474259 
       482250 485249 491252 499246 504247 507244 
  0.25 465840 463835 460837 455840 452841 448841 445843 444846 
       438860 431875 427883 427887 428888 427897 425905 424908 
       426914 430917 437918 442917 447908 449902 449896 449889 
       449886 450881 458869 462850 465840 
  0.25 422242 423238 422237 419236 416240 418241 421242 422242 
  0.25 357755 357752 355751 351750 343752 326758 309769 306771 
       303775 298781 291785 284791 283794 282798 283805 287810 
       291809 292807 296800 300794 305787 310781 315778 320777 
       327777 345766 353761 357755 
  0.25 262797 262794 259794 254795 249799 247802 245805 244808 
       242813 242818 243821 246823 250819 251815 253811 255808 
       257805 259802 262797 
  0.50 501237 499227 496219 492212 486208 479210 475218 470223 
       465227 459233 453235 450237 449243 446249 444255 442261 
       442266 446270 450271 455270 460267 466264 471258 480248 
       490238 498238 501237 
  0.50 452854 449851 447852 445857 444862 441867 438873 438877 
       439883 442882 444879 447875 449869 450864 452859 452854 
  0.50 354757 353753 352753 349754 347755 344757 342759 340761 
       338765 335767 336767 338765 341764 344763 346762 349761 
       351759 354757 354757 
  1.00 491225 490219 485216 482213 479217 478221 474225 471227 
       462233 458235 455240 453247 451251 450255 450259 453263 
       458262 462259 469253 475246 481240 483236 482231 482227 
       484222 486224 491225 
  1.50 478239 479234 476230 474229 469231 464233 461237 459241 
       457249 458255 461254 464251 468248 472243 475241 478239 
  2.00 469240 469238 467236 464238 466242 469241 469240 
  
  
 24HR QP VT 28/00Z
  0.01 484640 481631 478626 472621 468619 460617 456617 453619 
       447628 443637 439647 437650 434652 430654 422662 415672 
       409681 405692 403703 400710 380719 359731 349736 344739 
       341744 339751 339760 341763 345764 356762 360761 363762 
       363766 362771 362775 365775 368772 371771 378770 381770 
       386772 392779 396784 393788 388790 384794 377802 372805 
       368810 365813 363818 363825 367830 374832 379838 386848 
       393854 409864 418867 425865 430862 435863 439864 442867 
       445872 447874 453867 460860 461863 460868 460873 461881 
       464889 468891 474887 476881 477874 476862 475848 472836 
       468831 462829 453828 444825 441823 442819 444815 443809 
       436802 432796 433790 435786 438785 444784 447783 453784 
       463787 471790 479792 482790 487791 494796 499796 502792 
       502783 498775 491765 488752 486746 483741 481738 480733 
       481726 483717 485705 487690 487684 484676 481669 481664 
       483654 484640 
  0.01 518278 519270 518264 516258 514255 510246 510241 512238 
       514232 513227 511217 511213 512209 519201 529184 531174 
       531170 531165 533153 536142 538130 540116 540108 538101 
       535097 532094 527093 523096 521099 517106 515110 514115 
       511118 510123 505132 502135 499136 495135 492133 485127 
       479124 472123 468123 465125 449130 446132 440132 437133 
       434136 427152 423155 420148 416148 414150 415153 413157 
       414163 419165 420168 419170 416172 415178 418177 417183 
       418185 421189 425190 430188 431185 431182 430179 430175 
       434173 438172 440174 436183 436188 436195 440201 441208 
       440211 435209 430204 428201 424198 418197 409196 402200 
       389203 389208 390213 395220 396222 395224 392226 389229 
       388236 389243 390248 393252 400257 408259 424259 432260 
       439259 455257 463259 472263 480266 484266 487269 490274 
       492278 498285 504289 509289 515286 
  0.01 481195 482191 476185 474183 468181 465183 461189 458191 
       455195 454200 457202 460200 466202 469200 474198 478196 
       481195 
  0.01 319059 319049 318045 314033 308022 302014 298009 293007 
       290006 287008 284012 278021 270015 261010 256008 252009 
       248012 246015 246019 248027 250030 254035 258037 263038 
       269039 277046 283055 288065 291075 294081 298085 304087 
       307085 310078 312071 317069 318065 319062 319059 
  0.25 479685 478679 476674 472668 467664 462661 458659 453659 
       446661 440666 434674 432679 427690 419703 417715 416723 
       417727 419730 423741 423746 420748 415750 409752 406755 
       405763 406767 407772 412776 417778 427778 438775 446772 
       448767 450759 453752 462742 468730 477702 479692 479685 
  0.25 532121 533116 531112 531111 528110 528111 525116 525117 
       525120 525122 528125 531124 532121 
  0.25 510179 512170 512165 511162 505154 500151 494150 491151 
       489152 485156 482157 476155 473154 468149 466149 463152 
       466157 469162 473164 475170 480180 483183 488186 496194 
       501191 505188 510179 
  0.25 501228 501221 500212 498206 495203 491201 489201 484203 
       474206 465210 455212 446217 437217 426222 418228 413229 
       409232 404235 402239 402244 403246 407250 416251 428249 
       437246 447244 453244 459246 470248 477249 482252 486254 
       489254 492249 492243 492239 493235 499232 501228 
  0.50 474690 474683 472678 470674 467671 457670 452668 446671 
       441678 438683 432695 430703 429710 428717 429723 433729 
       436732 448737 453736 459732 462726 465719 467711 469705 
       472699 474691 474690 
  0.50 496227 497217 496212 491209 486208 476210 470215 460216 
       454216 451222 449226 447227 444226 438225 436225 430228 
       427231 420233 413234 410237 409242 412245 418246 423246 
       430243 434240 440239 449238 452236 458238 461237 465239 
       469242 475243 479243 481235 483227 487226 493227 496227 
  0.50 498177 500173 501168 499164 498163 496161 493160 490160 
       488161 487161 484162 481164 479168 481172 481173 483176 
       486178 488179 489179 492180 493180 494180 498178 498177 
  0.50 440761 440756 437753 434753 431755 429756 426757 423758 
       420759 420760 418763 418765 419766 421767 423769 425770 
       427770 430771 433770 436769 438766 440761 440761 
  1.00 447715 446711 445711 442711 442714 444716 447716 447715 
  1.00 493171 493170 490168 487169 486170 486171 489175 490175 
       492173 493171 
  1.00 485219 485216 482213 479215 477216 478217 481218 484219 
       485219  
  
 

 
 
 

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